permitted development rights: domestic wind turbines and air source
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Housing, Regeneration and Planning Permitted Development Rights: Domestic Wind Turbines and Air Source Heat Pumps
Transcript of permitted development rights: domestic wind turbines and air source
Hous
ing,
Reg
ener
atio
n an
d Pl
anni
ng Permitted Development Rights:Domestic Wind Turbines and Air
Source Heat Pumps
PERMITTED DEVELOPMENT RIGHTS: DOMESTIC WIND TURBINES AND AIR SOURCE HEAT PUMPS
SQW Energy
Scottish Government Social Research 2009
The views expressed in this report are those of the researcher and do not necessarily represent those of the Scottish Government or
Scottish Ministers.
© Crown Copyright 2009 Limited extracts from the text may be produced provided the source
is acknowledged. For more extensive reproduction, please contact the Queens Printers of Scotland, Admail, ADM 4058,
Edinburgh EH1 1NG. Email: [email protected]
This report is available on the Scottish Government Social Research website only www.scotland.gov.uk/socialresearch.
Table of Contents
1 INTRODUCTION 1 Introduction 1 Purpose of this study 1 Methodology 1 The Structure of this Report 3
2 CONTEXT 4 Policy Context and Scottish Government Objectives 4 Status of Permitted Development Rights 4 Additional Legislation Pertinent to DWT and ASHP 5 Previous Scottish Consultation: PDR for Microgeneration Equipment 6
Small Wind - Visual and Noise Impact Criteria 6 Small Wind - Scale and Height Impact Criteria 6 Small Wind - Natural and Built Heritage Impact Criteria 7 Small Wind - Control of Visual Impact 7 Air Source Heat Pump Impact Criteria 7 Summary of Stakeholder Attitudes to PDR 7
PDR Proposals for DWTs and ASHPs in England and Wales 8 Comparison of UK PDR proposals 8
3 LITERATURE REVIEW Domestic Wind Turbines 9
About Domestic Micro Wind Turbines 9 Turbine Topologies 10 Wind Resource and DWT Performance 10 EST: “Location, Location, Location”, Domestic Wind Field Trial 11 The Carbon Trust and the UK Met Office: “Small-Scale Wind Energy, Policy Insights and Practical Guidance” 11 Impacts of DWTs 12 Vibration 14 Ecology and Heritage 14 Small and Micro Wind Turbine Industry and Market 15 Summary of Key Findings for DWTs 15
Air Source Heat Pumps 16 Introduction 16 Technology Overview 16 Current and Potential Market 17 Costs & Benefits 17 Impacts 18 Additional Permitted Development Considerations 18 Summary of Key Findings for ASHPs 19
Microgeneration Certification Scheme and Microgeneration Installer Scheme 19 DWT Microgeneration Certification Scheme Product Standards 20 DWT Performance Standards & Certifications 20 DWT Installer Standards 21 Current MCS Standards Relating to DWT Impact Mitigation 21 ASHP Product Standards 23 ASHP Performance Standards & Certifications 23 ASHP Installer Standards 24 Current MCS Standards Relating to ASHP Impact Mitigation 24 Summary of Key Findings for MCS and MIS Schemes 25
4 STAKEHOLDER CONSULTATION 26 Pre-workshop Questionnaire 26 Workshops: 26 Conclusions 27
5 FINDINGS: MICRO WIND TURBINES 28 Noise 28
General 28 Absolute or Locational Noise Limit 28 Specific Noise Limits 29
Vibration 30 Visual 31 Electro-Magnetic Interference (EMI) 32 Flicker 32 Built Heritage 33 Natural Heritage 33 3 Year review 33 Prior Notification 34 Promoting Simplicity 34 Impact Matrix Summarising Key Points 34
6 FINDINGS: AIR SOURCE HEAT PUMPS 37 Noise 37 Vibration 38 Visual 39 Built Heritage 39 Natural Heritage 40 Other Issues 40
Reverse Operation 40 Performance 40 3 Year Review 40 Prior Notification 40
Impact Matrix Summarising Key Points 40 7 ASSESSMENT OF PERMITTED DEVELOPMENT OPTIONS
PDR Principles 42 PDR Conditions for a Specific Noise Criterion 42 Vibration – DWTs and ASHPs 45 Adoption of the MCS and Microgeneration Installers Scheme (MIS) Standards 46 Visual Impact: Building Mounted DWTs 47 Visual Impact: Stand-alone DWTs 47 Appropriate Number of DWTs per Curtilage 48 Visual Impact – ASHPs 48 Aircraft Safety – DWTs 48 Natural Heritage and Landscape Impacts – DWTs Only 49 Built Heritage 50 General Recommendations Surrounding PDR for ASHP and DWT 50
Prior Notification 50 3 Year Review of Permitted Development Rights 51 Anemometers for DWT 51 Decommissioning of Unused Equipment 51
8 CONCLUSIONS AND SUMMARY RECOMMENDATIONS 53 9 BIBLIOGRAPHY 55
10 APPENDICES 58 APPENDIX 1 – RESEARCH TOOLS Stakeholder Consultation Questions 58 Stakeholder Consultation Response Summary 62
Introduction 62 Summary of Responses 62
APPENDIX 2 – STAKEHOLDER CONSULTEES Companies and Organisations Consulted 70
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1 INTRODUCTION Introduction
1.1 This introductory chapter sets out the purpose of this study, outlines the methodology and provides an overview of the report structure.
Purpose of this study
1.2 According to the Department of Trade and Industry’s (DTI) Microgeneration Strategy published in March 20061, about 40% of the UK’s electricity demand could be met by installing microgeneration equipment on all types of buildings by 2050. Microgeneration technologies can also supply local heat demands and could therefore potentially help the Scottish Government achieve its objectives of ensuring reliable sustainable energy supply while tackling climate change.
1.3 It is acknowledged that world-leading Scottish manufacturers of both domestic wind turbine (DWT) and air source heat pump (ASHP) microgeneration technologies exist with the potential for local wealth creation.
1.4 Current circumstances relating to popular demand, climate change, renewables targets and the economy thus provide the microgeneration industry with the opportunity to expand. The Scottish Government is keen to assist the speed of this with the removal of unnecessary barriers.
1.5 A permitted development is one where planning permission is granted as a right and there is no need to apply to the planning authority. Householders can make certain types of minor changes without needing to apply for planning permission. These are called Permitted Development Rights (PDR) and derive from a general planning permission granted not by the local authority but by Parliament.
1.6 The purpose of this study is to identify, understand and evaluate the benefits and impacts associated with both DWT and ASHP so as to provide the evidence for appropriate recommendations to Scottish Ministers on the granting of PDR in planning legislation to the two technologies.
Methodology
1.7 PDR had not previously been granted to either DWTs or ASHPs due to a number of unresolved issues which required further investigation. These issues related to the specific impacts of each technology on people, natural and built heritage.
1.8 Although there are some common issues, each technology has its own set of characteristics and was therefore treated separately in this research. The following tasks were therefore undertaken for both DWTs and ASHPs:
1 May be viewed at http://www.berr.gov.uk/files/file27575.pdf
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• Assessment of the technology with regard to character and potential for meeting heat and power demands
• Identification of any potential impacts • Evidence of actual and possible impacts • Determination of reasonable or allowable impact levels
1.9 The cost benefit balance of each technology was examined to assess firstly
whether it was worthwhile installing and secondly, what evidence there was that the installation could cause a significant impact on neighbours or amenity.
1.10 A large and comprehensive body of evidence was investigated. The evidence gathered specifically related to:
• DWT and ASHP technology status: in terms of technical specification, performance, innovation, efficiency improvement, cost, current and future trends
• Technology and Manufacturing Assurance: in terms of certification schemes, independent third party compliance and performance testing and health and safety
• Policy and Regulatory Frameworks: in terms of the current Scottish legislative framework in which PDR reside, and any likely changes predicted.
1.11 The ‘impact approach’2 was chosen as being that most appropriate on which to
evidentially base PDR as it provides the best route to satisfactorily mitigating the actual realised impacts.
1.12 As all development will have an associated cost, the likely negative impacts of each technology were deduced using the best available evidence from both the literature, and through direct consultation with experts in the field. A written questionnaire was used to gain insight from Scotland’s leading practitioners into the technologies and their impacts.
1.13 The DWT and ASHP impacts were therefore identified and catalogued. Each identified impact was then further researched and consulted through a series of Stakeholder workshops to determine a suitable or allowable impact level under which a development or technology could obtain PDR.
1.14 In addition the practicalities and operational issues of granting PDR were investigated at the Stakeholder workshops so as to produce a pragmatic and workable regime for all concerned.
1.15 Figure 1 describes the logic chain that captures the basic methodology.
2 An impact approach seeks to regulate developments by their assessed measurable impacts; usually in terms of scale and extent.
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Figure 1: Outline methodology to produce recommended PDR criteria for domestic wind turbines and air-source heat pumps
Source: SQW Energy
The Structure of this Report
1.16 The remainder of this report is structured as follows:
• Chapter 2 examines the policy context and current status of Permitted Development Rights for DWT and ASHP.
• Chapter 3 provides technology reviews for DWT, ASHP, the associated Microgeneration Certification Scheme (MCS), and the Microgeneration Installers Scheme (MIS).
• Chapter 4 briefly outlines the stakeholder consultation methodology. • Chapter 5 explores the stakeholder views and provides an analysis of the
findings on PDR for ASHPs. An impact matrix summarising the key points concludes this chapter.
• Chapter 6 explores the stakeholder views and provides an analysis of the findings on PDR for DWTs. An impact matrix summarises the key points.
• Chapter 7 sets out the options for a PD regime including the practicalities and operational issues. Recommendations and their justification are outlined.
• Chapter 8 presents the conclusions and summarised PDR criteria recommendations for both DWTs and ASHPs.
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2 CONTEXT Policy Context and Scottish Government Objectives
2.1 The power in the wind represents a vast source of energy, Scotland having the largest potential wind energy resource in Europe. DWTs have recently become more popular with small units attaching directly to the roof while larger units can be installed with their own support mast.
2.2 Similarly ASHPs are a well established technology (especially in Nordic countries and North America) that have the potential to increase energy efficiency and reduce carbon emissions.
2.3 The Scottish Government has taken an active role to assist the development of microgeneration technology recognising its contribution towards mitigating climate change, meeting future renewables targets, and not least encouraging the development of a domestic industry with export potential. A key part of the Scottish Government’s role has been and continues to be the removal of unnecessary barriers within the planning system.
2.4 It is clear from both the Scottish Government and the previous consultees responses* that :
“the (PDR) proposals seek to strike the right balance between controlling the adverse impacts on neighbours and amenity generally, and the wider environmental benefits of CO2 emissions reductions”.
Status of Permitted Development Rights
2.5 Within the policy context and in order to achieve the Government’s objectives, the following paragraphs outline the salient consultations and Orders that have informed this further research into PDR.
2.6 The Town and Country Planning (General Permitted Development) (Scotland) Order 1992 (the GPDO) was reviewed in 2007, the reviewers suggesting that it would be appropriate to give PDR to certain categories of microgeneration for domestic properties3.
2.7 Additionally Scottish Planning Policy (SPP) 6, Renewable Energy (March 2007**) indicated the intention to positively consider extending PDR so that more microgeneration equipment could be installed at existing buildings without the need to apply for planning permission.
2.8 Subsequently in March 2008 the Scottish Government launched its consultation Permitted Development Rights for Microgeneration Equipment4. It sought
3 This document can be viewed at: http://www.scotland.gov.uk/Publications/2007/03/29102736/0 4 This document can be viewed at: http://www.scotland.gov.uk/Publications/2008/03/04090052/0 * This document can be viewed at: http://www.scotland.gov.uk/Publications/2007/03/29102736/0 ** This document can be viewed at: http://www.scotland.gov.uk/Publications/2007/03/22084213/0
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views on the extent to which planning control could be reduced for domestic buildings and included proposals for granting PDR for DWT and ASHP based on distance criteria. It also discussed the use of a technical threshold for noise and said that in the longer term an approach based on accreditation schemes for installers and equipment may provide a basis for PDR. The latter is a reference to the Microgeneration Certification Scheme5.
2.9 The Town and Country Planning (General Permitted Development) (Domestic Microgeneration) (Scotland) Amendment Order came into force on 12 March 2009. It was informed by responses to the above mentioned consultation paper6. An analysis of the consultation responses is also available7. The Order grants PDR for solar panels, biomass systems, combined heat and power, ground source heat pumps and water source heat pumps on domestic buildings. DWTs and ASHPs are not included. At the time it was not possible to resolve the issues relating to these technologies within the same timescale as the others, but the Order was laid before Parliament with a commitment from Ministers to undertake this study. The issues previously identified include noise, aerodrome safeguarding, vibration, cumulative effects, impact on designated areas and visual impacts.
2.10 The Climate Change (Scotland) Act 20098 requires that an Order on PDR for DWTs and ASHPs be brought forward no later than six months from commencement (i.e. by February 2010).
Additional Legislation Pertinent to DWT and ASHP
2.11 It is notable that PDRs do not over-ride health and safety, environmental or amenity safeguards or the requirements of the Building Regulations.
2.12 Recent research for the Building Standards Division of the Scottish Government (SBS) entitled “Building Integration of Low and Zero Carbon Technology Systems”9 identified a number of risks associated with the installation of particular microgeneration equipment. These included risks to the structural integrity of the building, to the integrity of the building fabric, to its energy performance, and risks to the health and safety of people in or around the building. Building Standards requirements are concerned with maintaining the safety and environmental performance of the building. However the granting of PDR must in no way lead building owners to believe that they do not need to comply with the building regulations and, in certain cases, owners do need to apply for a building warrant.
2.13 Additionally with regard to listed buildings and protected areas certain protection from such developments is already afforded.
2.14 Although PDRs normally apply to all areas, planning authorities have powers under the GPDO (known as Article 4 Directions) which enable them to require
5 This can be viewed at: http://www.microgenerationcertification.org/ 6 Consultation responses are at: http://www.scotland.gov.uk/Publications/2008/08/28101947/0 7 This document can be viewed at: http://www.scotland.gov.uk/Publications/2009/02/06145853/0 8 May be viewed at: http://www.opsi.gov.uk/legislation/scotland/acts2009/pdf/asp_20090012_en.pdf 9 This document can be viewed at: http://www.sbsa.gov.uk/pdfs/building_integ_LZCT.pdf
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require planning applications for proposals which would otherwise have PDR. Such Directions do usually have to be confirmed by the Scottish Ministers.
Previous Scottish Consultation: PDR for Microgeneration Equipment
2.15 Table 1 outlines the suggested conditions set in the previous consultation for the Permitted Development of DWTs in Scotland10,11.
Table 1: Previous DWT PDR Recommendations for Scotland Normal Buildings Buildings in Areas Designated for their Built
and Natural Heritage PD for building mounted or free-standing turbines applies to houses well separated from neighbours and limited to one turbine per house, including the curtilage. A simple distance criterion of >100 metres to the nearest residential property.
Wind turbines would not be granted PD in areas designated for their built heritage.
Each DWT blade up to 1.1 metres in length, up to 3 metres above the highest part of the roof and one per building.
PD may be constrained for wind turbines in areas designated for their landscape quality.
Free-standing turbines - each blade up to 1.1 metres in length and a maximum height including tower of 11.1 metres to the tip of the turbine blade, located at least 12 metres from the boundary of the property and one per curtilage.
PD may be constrained for wind turbines on Listed Buildings.
Source: Scottish Government (2008) “PDR for Domestic Microgeneration Equipment - Consultation” Small Wind - Visual and Noise Impact Criteria
2.16 With regard to applying distance criteria for wind turbines to deal with the potentially adverse impacts respondents’ views were mainly divided into two categories:
• The 100m threshold (or other) criteria appears simple, easily understood and enforceable.
• A threshold was overly restrictive on technology development and PDR should be linked to the use of an accreditation scheme (such as the Microgeneration Certification Scheme) covering equipment standards and suppliers/installers.
2.17 A precautionary approach was therefore adopted for PDR given the technical
uncertainty and lack of data regarding potential noise and vibration nuisance from turbines.
Small Wind - Scale and Height Impact Criteria
2.18 The suggested limits on the scale of building mounted wind turbines are set out in Table 1 above. The proposals were viewed as restrictive by the renewables industry, most individual respondents and some environmental NGOs because
10 This document can be viewed at: http://www.scotland.gov.uk/Resource/Doc/213981/0056876.pdf 11 This document can be viewed at: http://www.scotland.gov.uk/Publications/2008/03/04090052/0
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they believed the limits may exclude many turbine models sold in Scotland. Some advocated PDR for a larger rotor diameter (3.5m), higher towers (up to 15m, reflecting Environmental Impact Assessment (EIA) triggering criteria) and no restriction on the number of turbines per curtilage.
2.19 Those disagreeing with the original proposals were also concerned about adverse impacts, such as cumulative effects of noise.
Small Wind - Natural and Built Heritage Impact Criteria
2.20 Concern was raised with respect to the impact of DWTs within Special Protected Areas (SPAs), Special Areas of Conservation (SACs), Sites of Special Scientific Interest (SSSIs) or Ramsar sites and on buildings known to contain bat roosts.
2.21 Similarly, architectural and archaeological heritage organisations recommended that PDR should not be granted within Conservation Areas.
Small Wind - Control of Visual Impact
2.22 Most of those that agreed with the setting of general conditions such as ‘provided the colour of the mast minimises its visual impact’ stressed the importance of conditions being clear and concise. Some pointed out that not only the colour but also the scale of turbines and siting may be an issue.
Air Source Heat Pump Impact Criteria
2.23 Table 2 outlines the suggested conditions set in the previous consultation for the Permitted Development of ASHPs in Scotland12.
Table 2: Previous ASHP PDR Recommendations for Scotland Normal Buildings Buildings in Areas Designated for their Built
and Natural Heritage Permitted if more than 100m from neighbouring house or flat.
Permitted if more than 100m from neighbouring house or flat.
Source: Scottish Government (2008) “PDR for Domestic Microgeneration Equipment - Consultation” 2.24 The consultees were fairly equally split as to whether ASHP should have PDR
with the provision that they should not be located within 100m of a separate house or flat. Again most of those that disagreed believed that a noise criterion was more appropriate, some of them suggesting the adoption of a certificate scheme based on noise performance. It was again highlighted that this may encourage manufacturers to develop quieter units.
Summary of Stakeholder Attitudes to PDR
2.25 It is notable that heritage organisations and planning authorities tend to favour a cautious and traditional approach with tighter conditions and thresholds for PDR, while environmental NGOs and the renewables industry generally support more permissive PDR for DWTs and ASHPs.
12 This document can be viewed at: http://www.scotland.gov.uk/Resource/Doc/213981/0056876.pdf
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2.26 Additionally there seemed to be an implied view that: “PD should reflect the carbon payback period of the equipment… and that the more efficient the equipment, the higher should be the level of acceptable impacts on neighbouring properties.”
2.27 The summary of stakeholder attitudes therefore frame the need for an analysis of the available PDR options based on the most up to date information and stakeholder views. This research aims to undertake such an evaluation.
PDR Proposals for DWTs and ASHPs in England and Wales
2.28 Table 3 and Table 4 relate the present proposals for PDR in England and Wales. A consultation is presently expected which will attempt to examine the impacts and issues associated with extending PDR to DWTs and ASHPs.
2.29 As in the previous Scottish consultation, the impact issues that prevented either DWTs or ASHPs to gain PDR may be summarised as those related to visual impact, noise impacts, vibration and impacts on heritage.
Table 3: Summary of current PDR proposals for DWT in England and Wales Building Mounted DWTs Stand Alone DWTs Permitted if <3m above ridge (including the blade) and diameter of blades <2m
Permitted if <11m (including the blade) high and diameter of blades <2m
Internal noise <30dB, external noise <40dB, “garden” noise <40dB
Internal noise <30dB, external noise <40dB, “garden” noise <40dB
Up to 4 turbines on buildings >15m At least 12m from a boundary Vibration < 0.5mm/s Vibration < 0.5mm/s Should not be installed on the curtilage of a Listed Building
Should not be installed on the curtilage of a Listed Building
Buildings in Conservation Areas and World Heritage Sites – Not Permitted
Buildings in Conservation Areas and World Heritage Sites – Not Permitted
Source: CLG (2007) “PDR for Householder Microgeneration” Government response to consultation replies.13 Table 4: Summary of current England and Wales PDR proposals for ASHP Normal Buildings Buildings in Areas Designated for their Built
and Natural Heritage ASHP to be PD subject to new standards and safeguards on, in particular, noise and vibration.
ASHP to be PD subject to new standards and safeguards on, in particular, noise and vibration.
Source: CLG (2007) “PDR for Householder Microgeneration” Government response to consultation replies. Comparison of UK PDR proposals
2.30 It is notable that the English and Welsh proposals have attempted to use an impact approach based on measurable impact levels rather than the ‘distance based’ criteria previously consulted on in Scotland.
2.31 A desirable outcome of any Scottish PDR Regime would be that it is similar or comparable to that eventually implemented in England and Wales. The reason for this is that equivalent schemes are likely to lead to least confusion, allow for similar standards and encourage faster technology development due to a coherent UK wide market.
13 Document at: http://www.communities.gov.uk/documents/planningandbuilding/pdf/565952.pdf
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3 LITERATURE REVIEW Domestic Wind Turbines
About Domestic Micro Wind Turbines
3.1 This section presents a summary of the recent and relevant literature available about DWTs. A brief overview of how the technology operates is given, followed by the current status of the technology’s installation levels in the UK and an assessment of the potential UK market. The costs and benefits of DWTs are then discussed with an evaluation of the typical economic and CO2 savings that could be achieved versus other forms of generation. The section then goes on to describe the main impacts of DWTs from a planning perspective and explains the standards and certifications that are in place or may be needed to minimise any adverse impacts. A brief outline of the potential options being considered in the rest of the UK is presented along with specific considerations that may need to be addressed. Finally, a key findings section is presented.
3.2 DWTs are a relatively recent development designed to sustainably provide a proportion of locally consumed energy, and potentially some electricity export to the local distribution network. DWTs tend to be rated in the region of a few kilowatts (kW) and convert the kinetic energy of moving air (wind) into useful mechanical power by means of a rotating aerofoil.
3.3 The DWT’s rated power indicates the (maximum) output at a specific wind speed, however the useful energy output over a year is highly dependent on the location of the DWT; specifically the available energy in the wind at that site.
3.4 It is particularly relevant to note that the power produced by a DWT is related to the cube of the wind speed, for example a wind speed of 5 metres per second (m/s) should contain almost twice as much power as a wind of 4m/s. The wind speed is therefore by far the most critical parameter with regard to possible energy output. The second most critical parameter for energy production is the rotor swept area14. The DWT Coefficient of Performance is the third most important parameter – refer to Box 1.
14 Rotor swept area refers to the area of wind that the blades ‘cut’ through during one revolution.
BOX 1: DWT Performance Metrics
The Coefficient of Performance (Cp) is the proportion of the energy in the moving air (wind) that a particular turbine can extract. The Laws of Physics state the maximum Cp to be the Betz limit of around 59.3%.
The Load Factor or Capacity Factor is the percentage of energy a wind turbine yields in any given year in comparison to its maximum theoretical energy yield in the same year. This is due to wind speed variability or the availability of the machine to generate.
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3.5 According to the two most critical energy production factors (wind speed and swept area) it is apparent that fully functional DWTs with small rotor areas in urban areas of low wind speed are at a distinct disadvantage in terms of energy production or load factor (see Box 1). The carbon payback and benefit is directly proportional to the energy production of the DWT, which in turn is intrinsically linked to the wind speed at the point of installation.
3.6 It should be noted that there is a minimum cut-in wind speed required before any DWT rotor will start to turn. This is normally around 3 to 4m/s for most DWTs. Below this wind speed the DWT will produce no energy.
Turbine Topologies
3.7 There are two distinct types of wind turbines: Horizontal Axis Wind Turbines (HAWTs) and Vertical Axis Wind Turbines (VAWTs). The rotor blades of HAWTs move perpendicular to the ground, while the blades of a VAWT move parallel to the ground (Figure 2).
3.8 There are two main DWT mounting methodology sub-divisions related to PDR: building mounted DWTs; and stand-alone mast, or pole mounted DWTs.
Figure 2: A VAWT (stand alone) and a HAWT system (building mounted)
Source: Ropatec VAWT and Renewable Devices Swift HAWT Wind Resource and DWT Performance
3.9 Measurement or accurate prediction of the wind resource at any site is key to evaluating DWT performance. As there is no such thing as a typical site; the best single indicator of the wind energy at a specific site is its long-term annual mean wind speed, averaged over several decades. The two major factors affecting wind-speed are:
• Wind shear - due to the ground’s or obstacles’ (trees, houses, etc.) drag effect
• Turbulence - for example, obstacles in urban areas greatly increase inconsistency or rapid changes in wind direction and speed.
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3.10 The recognised lack of suitable locally available high resolution wind resource data and DWT device performance information for customers has led to a number of well researched independent studies, some of which are outlined below.
EST: “Location, Location, Location”, Domestic Wind Field Trial15
3.11 In 2007 the Energy Saving Trust (EST) launched the first ever comprehensive monitoring programme of domestic small scale wind turbines in the UK. The study included 57 EST monitored sites, 29 Warwick Wind Trial16 monitored sites and 68 additional sites. Table 5 summarises the monitored DWT performance.
Table 5: EST and Warwick Wind Trial summary of monitored performance Impacts Maximum Load
Factor (Scotland)
Maximum Output (kWh p.a.17)
Carbon Offset (tonnes p.a.)
Owner Income (£ p.a.)
Building Mounted 3% 395 0.2 51Rural Stand-alone 30% 3942 2.1 510Rural Building Mounted (at gable end)
7% 975 0.5 127
Source: Energy Saving Trust 2009, “Location, location, location: Domestic small-scale wind field trial report” 3.12 The figures in Table 5 clearly show the performance differences between
building mounted and stand alone DWTs. It is particularly notable that the maximum load factor for a building mounted (rural) DWT is 7% compared to a rural stand-alone DWT with 30% (comparable to large utility sized wind turbines).
3.13 The accuracy of wind speed prediction models was also assessed along with the minimum wind-speed for a DWT. EST states that
“a potential customer’s site should receive a wind speed prediction of at least 5m/s, when assessed using the MCS NOABL or Carbon Trust tool, but will always recommend that anemometry is installed whenever possible prior to installing a DWT”.
The Carbon Trust and the UK Met Office: “Small-Scale Wind Energy, Policy Insights and Practical Guidance”18
3.14 The main findings widely mirror and agree with the EST study and the conclusions are summarised as:
15 Location, location, location Domestic small-scale wind field trial report, Energy Savings Trust, July 2009. http://www.energysavingtrust.org.uk/Global-Data/Publications/Location-location-location-The-Energy-Saving-Trust-s-field-trial-report-on-domestic-wind-turbines 16 Warwick Wind Trials (Entec 2006-2009) http://www.warwickwindtrials.org.uk/ 17 A 2.2m 1.5kW MWT is used for comparability of maximum benefit under suggested PDR limits. 18 At http://www.carbontrust.co.uk/Publications/publicationdetail.htm?productid=CTC738&metaNoCache=1 and http://www.carbontrust.co.uk/NR/rdonlyres/6A29EA3A-C9B1-4129-849A-554030DEA081/0/SmallscaleWindEnergyTechnicalReport.pdf
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• The urban environment has a dramatic impact on wind speed and generation capacity
• This impact varies considerably with height relative to roof-top. Significant improvements [in energy output capacity factors] can be gained by mounting above roof-top, but heights several meters above rooftop are likely to be required
• Rural turbines typically have higher capacity factors, with 15%-20% being typical and more being achievable at some locations.
3.15 While there is no doubt that the market for DWTs and some of the devices
themselves may still be under development, the conclusions that may be drawn from the independently monitored DWTs (Table 5 ) are clear:
• Rural stand-alone DWTs perform very well both economically and with capacity factors (energy output) approaching those of utility sized wind turbines
• Building mounted DWTs do not perform well: their best capacity factors are a factor of between 4-10 times less than large wind; and their costs are between 2-8 times more expensive per kW than utility scale wind. Compared to utility wind, building mounted DWTs would therefore require up to 80 times more finance to provide the same energy output and carbon savings. On current evidence it is unlikely that most building mounted DWTs will pay back economically over their specified lifetimes, and carbon payback would be marginal.
Impacts of DWTs
3.16 The following have been identified as the major (real or perceived) potential planning impacts of DWTs.
Visual (the trade off between visual impact and power capture)
3.17 Considerations for the aesthetics of wind turbines will ultimately introduce a degree of subjectivity, making the quantification of visual impacts particularly difficult. The common factors that tend to affect the perception of wind turbines are:
“distance to turbines, their size and number, paint and structure, weather conditions, how often, how long, and where people are faced with turbines” 19.
3.18 An Entec study for Communities and Local Government20 determined that the visual impact of wind turbines is correlated with size of the structure and as
19 Möller, B “How Wind Power Landscapes Change: An Attempt to Quantify Visual Impact on Land Use and Residents in Northern Jutland, Denmark” 20 Communities and Local Government (2007) “Changes to Permitted Development: Consultation Paper 1: Permitted Development Rights for Householder Microgeneration” P. 23.
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such, more planning applications are approved for turbines under a certain height21 (10 metres (m)).
3.19 However any given wind turbine height restriction must allow for an optimum level of performance. The Carbon Trust suggests that
“should PDRs be reviewed in future… serious consideration [is given] to setting a height limit for stand-alone turbines of more than 11m to the blade tip for open, exposed sites of a rural character… this is to maximise the carbon savings of small-scale wind energy given the sensitivity of generation to height”. Additionally “changing the limit on the height of the highest point of the turbine from 3 m to 4 m is estimated to increase power output by 30% to 40%, and increasing the limit to 10 m can increase power by a factor of 3 to 4 compared with a 3 m height limit”.
3.20 The height of a turbine will ultimately have an impact on visual appearance and as such limits should be set for a height which enables optimum performance but no higher22.
Noise
3.21 All DWTs will emit some level of mechanical or aerodynamic noise, the former normally being minimal. Aerodynamic noise is caused by a number of processes related to the rotor form, size and speed and therefore increases as wind speed increases.
3.22 Box 2 describes a number of noise measurements, however a sound’s unpleasantness is highly subjective and tends to depend on: loudness, frequency content, duration, intermittence, predictability and source. Turbine noise is also relative to any background noise and so consideration for the development of a DWT cannot be made without consideration for a specific site
21 Communities and Local Government (2007) “Changes to Permitted Development: Consultation Paper 1: Permitted Development Rights for Householder Microgeneration” P. 22. 22 Planning Service (2007) “Microgeneration Permitted Development Rights: consultation document” http://www.planningni.gov.uk/index/news/news_consultation/news_consultations_archive/news-legislation-pd-rights.pdf p.20
BOX 2: Measuring Noise
Sound power is the acoustical energy emitted by the sound source, and is an absolute value. It is not affected by the environment.
Sound pressure is a pressure disturbance in the atmosphere influenced not only by the strength of the source, but also by the surroundings and the distance from the source to the receiver. Sound pressure is what our ears hear.
Sound (power & pressure) is measured on the decibel (dB) scale.
0dB is the threshold of human hearing (20 µPa of sound pressure).
A 3dB increase is equal to a doubling in the sound pressure (only just noticeable to a human), however a 10dB increase equates to a doubling of loudness.
The A-weighted scale denoted dB(A) is often used in environmental noise standards as it approximates the sensitivity of the ear to various frequencies.
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(affecting the application of a universal noise limit). As a result, the definition of “readily acceptable, clear, simple and achievable noise limits”23 could be difficult to determine.
Vibration
3.23 Stand-alone pole mounted DWTs are unlikely to transmit noticeable vibrations due to the vibration absorbing properties of the earth.
3.24 All building-mounted systems will transmit some energy to their support structure, however the nature of the building fabric and the configuration of the structure will greatly affect how and where any vibration is observed. The most certain means for dealing with vibration is to avoid it in the first place by good design, or to limit its transmission to the structure by means of anti-vibration mounts. British Standards BS6472 “Evaluation of human exposure to vibration in buildings (1 Hz to 80 Hz)” and BS7385 “Evaluation and measurement for vibration in buildings” are applicable.
Ecology and Heritage
3.25 The European Commission suggests that as with other developments, the implementation of wind turbines must take into account the concerns for varying land use so that areas of natural beauty, national parks etc are not impacted detrimentally. Development should only occur where the existing value of the site is not compromised24. Most Heritage (World Heritage Sites, Conservation Areas, Listed Buildings), Landscape, and Natural Heritage designations are already protected against such development outside of PDR.
3.26 Although there is concern that DWTs can influence local fauna, e.g. “bird populations, bird habitats, breeding and feeding grounds, migration routes and other well-used flight paths” 25 a British Wind Energy Association (BWEA) review of existing evidence suggests that bird mortality from the turbines themselves is unlikely26. Ultimately the RSPB promotes the use of this renewable technology if there is strong monitoring of planning and environmental impacts27, recommending “that the potential effects of microgeneration equipment are monitored and the GPDO reviewed within a 3 year period to ascertain whether there are any negative impacts on birds and other species.”
23 Communities and Local Government (2007) “Changes to Permitted Development: Consultation Paper 1: Permitted Development Rights for Householder Microgeneration” P. 23. 24 European Commission (2006) “Administrative and Planning Issues for Small Wind Turbines in Urban Areas” http://www.urbanwind.net/pdf/Reports_Planning_and_admin_issues_Europe_report.pdf 25 DECC “Ornithology: Birds and Renewable Energy” http://www.decc.gov.uk/en/content/cms/what_we_do/uk_supply/energy_mix/renewable/planning/on_off_wind/ornithology/ornithology.aspx 26 BWEA “Small Wind and Frequently Asked Questions” http://www.bwea.com/small/faq.html#flicker 27 RSPB “Wind Farms” http://www.rspb.org.uk/ourwork/policy/windfarms/index.asp
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Small and Micro Wind Turbine Industry and Market
3.27 The market for small and micro wind systems in the UK is the second largest in the world accounting for 25% of global demand and the sector has been growing at an annual rate of 80%28. Since 2005, over 10,000 micro and small wind turbines have been deployed in the UK equating to over 20MW of installed electrical capacity of which 7.24MW was installed in 2008 alone29. Table 6 shows the cumulative installed small wind systems in the UK.
Table 6: Cumulative number of installed UK small wind systems Capacity 2005 2006 2007 2008 0 - 1.5kW 992 2,935 6,082 8,878 1.5 - 10kW 155 424 1,025 1,600 Source: BWEA (2009) “Small Wind Systems: UK Market Report” 3.28 Table 7 provides a costed estimate of the likely level of small and micro wind
turbine market penetration. The Carbon Trust states that “if 10% of households installed turbines at costs of energy below 12p/kWh (indicative of the current retail electricity price), up to 1.5TWh could be generated and 0.6 MtCO2 saved. Relative to total electricity consumption and emissions from power generation, these figures are fairly low.”
Table 7: Estimates of UK small wind resource from cost curves Technology <12p/kWh 10%
Market Penetration <35p/kWh 10% Market Penetration
<100p/kWh 10% Market Penetration
Rural Small and Micro Scale 1.5 TWh/year 3.2 TWh/year 3.4 TWh/year Urban Small and Micro Scale 0 TWh/year 0.1 TWh/year 0.3 TWh/year Source: Carbon Trust, 2009, “Small-scale Wind Energy, Policy Insights and Practical Guidance” 3.29 In summary the resource cost evidence indicates that rural DWTs are already
capable of making a small contribution to UK electricity demand which was around 351TWh in 2007/0830. Dependent on the introduction and value of a Feed in Tariff (FIT), DWT contributions could eventually meet 1% of total UK electricity demand. On present evidence urban DWTs are unlikely to provide significant contributions to UK electricity supply.
Summary of Key Findings for DWTs
3.30 DWTs are a proven technology which when correctly sited can help meet the electricity or heating requirements of a domestic residence.
3.31 There is little evidence that urban building mounted DWTs are a good investment or produce significant amounts of useful energy. This is because there tends to be insufficient wind resource in such locations which are often also highly turbulent.
3.32 In contrast suitably sited rural DWTs can provide excellent returns on investment and significant energy contributions to local demand.
28 AWEA (2008) “Small Wind Turbine Market Global Study” 29 http://www.bwea.com/pdf/small/BWEA%20SWS%20UK%20Market%20Report%202009.pdf 30 2008 Energy Market Outlook - BERR, UK http://www.berr.gov.uk/files/file49433.pdf
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3.33 The main impacts of DWTs from a planning standpoint are noise, vibration, visual, natural heritage, and electromagnetic interference. UK standards and best practices are in place to mitigate these factors under the Microgeneration Certification Scheme which is discussed in the next section.
Air Source Heat Pumps
Introduction
3.34 This section presents a summary of the most recent and relevant literature available about ASHPs. A brief overview of how the technology operates is given, followed by the current status of the technology’s installation levels in the UK and an assessment of the potential UK market. The costs and benefits of ASHPs are then discussed with an evaluation of the typical economic and CO2 savings that could be achieved versus other forms of heating. The chapter then goes on to describe the main impacts of ASHPs from a planning perspective and explains the standards and certifications that are in place or may be needed to minimise any adverse impacts. A brief outline of the potential options being considered in the rest of the UK is presented along with specific considerations that may need to be addressed. Finally, a key findings section is presented.
Figure 3: The outside heat absorption unit of an ASHP system
Source: Mitsubishi 2009 Technology Overview
3.35 An ASHP is an energy efficient, low carbon technology that absorbs heat from the outside air and concentrates the heat inside a property. ASHPs use mains electricity (from the National Grid or generated locally) to power the system and therefore cannot strictly be classified as a renewable energy technology or a micro-generation device – they are an energy efficient device. The ASHP typically comprises of two main parts namely the heat absorption unit (usually situated outside the property) and the heat dissipater unit situated inside the property.
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3.36 ASHPs are a relatively mature technology, deriving their technological heritage from air-conditioning unit design. In the UK, an increasing number of ASHP manufacturers and suppliers have emerged, triggered by the need to install more carbon and energy efficient heating devices.
Current and Potential Market
3.37 Although ASHPs are very popular in Scandinavia, Japan and Canada, they are relatively new to the UK market. Until recently, the UK heat pump market has been dominated by the Ground Source Heat Pump (GSHP) technology with only 150 units of ASHPs installed in the UK compared with a total of 95,000 -98,000 microgeneration technologies installed at the end of 200731. The technology is suited to homes that are well insulated with underfloor heating and/or water heating. It gives best economic and carbon performance when installed in homes that are off gas-grid - ASHPs cannot currently compete economically with natural gas, however possible future price rises may change this. ASHPs do not tend to be used with radiator heating systems as the low temperature technology generally needs oversized radiators to be efficient.
3.38 ASHPs have been identified as a more practical technology (versus GSHP) to meet the increasing demand for space heating in the UK residential sector as they are easier to install and more suitable for higher density housing, retrofit and new builds32. According to the Department for Business, Enterprise and Regulatory Reform (BERR), there could be significant growth in the number of ASHPs in the UK – see Table 8.
Table 8: Estimates of Cumulative Installations of ASHPs under a Baseline Scenario of Existing Policies Only Technology 2007 (Actual) 2020 2030 2050 ASHP 150 49,400 155, 800 423, 500 Source: BERR 2008, “The growth potential for Microgeneration in England, Wales and Scotland”. Costs & Benefits
3.39 According to the Energy Saving Trust (EST), the cost of a typical domestic ASHP system suitable for a well insulated detached property is around £5,000 to £10,000 installed (ex VAT)33, with running costs of around £79034. The costs of installing ASHPs vary considerably depending on size, model, make and the property they are installed in. ASHPs can provide considerable carbon savings, but this depends on the type of fuel that it displaces and the level of insulation in a property – ASHPs only work effectively in well insulated properties.
3.40 ASHPs can deliver several benefits to domestic householders including economic savings, increased energy efficiency and a reduced carbon footprint.
31 BERR (Element Energy), 2008, The growth potential for Microgeneration in England, Wales and Scotland. P.9. [Online] BERR. Available at: http://www.berr.gov.uk/files/file46003.pdf 32 Ernst & Young, (2007) ‘Renewable Heat Support Mechanism’. P.16. [Online]Defra/BERR. Available at: http://www.berr.gov.uk/files/file42043.pdf 33 http://www.lowcarbonbuildings.org.uk/micro/air/ 34 Energy Savings Trust, 2009, http://www.energysavingtrust.org.uk/Generate-your-own-energy/Air-source-heat-pumps
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Greatest savings are typically made when displacing grid electricity or solid fuel as the main heating source in a dwelling – these displaced fuels tend to be less efficient and have higher carbon factors35. Gas and oil are typically more efficient and have low carbon emission factors. Table 9 outlines typical savings that can be expected from an ASHP.
Table 9: Savings with an Air Source Heat Pump Fuel Displaced £ Saving per year CO2 saving per year Gas £50 No SavingElectricity £700 5000 kgOil £20 No SavingSolid £460 4600 kgSource: Energy Saving Trust 3.41 The above information is the product of research and desktop modelling
undertaken by the Energy Saving Trust36. The savings assume that hot water is preheated by an ASHP and heated to full temperature by an immersion heater (50:50) and that the property has good insulation: loft insulation, cavity wall insulation where applicable, primary pipework insulation and thermostatic valves.
3.42 The Energy Saving Trust currently has full field trials on-going with approximately 40 ASHPs being monitored across the UK. The results are expected to be published in 2010, giving a more detailed picture of the carbon and cost performances of ASHPs.
Impacts
3.43 ASHPs have the potential to be detrimental to neighbouring amenities and the wider environment. However, the level of impact of ASHPs is often subjective, site sensitive and should therefore be considered on an individual basis. Table 10 summarises the main impacts associated with ASHPs.
Table 10: Summary of the Impacts of Air Source Heat Pumps Impacts Summary Noise and Vibration Noise is emitted from the fan and compressor which
can be a nuisance. Vibration occurs through building structures especially for wall mounted ASHPs
Visual Limited- this will be due to the external fan and coil installation
Source: NHBC Foundation (2002) A review of microgeneration and renewable energy technologies Additional Permitted Development Considerations
3.44 Given that the primary aim of granting PDR to ASHPs is to reduce carbon emissions, consideration should be given to whether PDR should be granted to all ASHP technologies, or just uni-directional models (other than during defrost
35 Energy Savings Trust, 2009, http://www.energysavingtrust.org.uk/Energy-saving-assumptions/Generate-your-own-energy-assumptions 36 Energy Saving Trust with assumed CoP of approximately 2.5. All savings are approximate and are based on an air source heat pump providing 100% of space heating and up to 50% of hot water, with the additional 50% provided by electric heater, in a detached property.
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cycles). Most types of ASHP have the ability to run in reverse whether as a mode of operation, or simply as part of its defrost cycle. In reverse mode, some ASHPs can effectively be working as an air conditioning or cooling unit, and in this mode consume considerable amounts of energy. If PDR is granted for bi-directional ASHP, the outcome may be to effectively grant PDR for air conditioning units, which are very carbon intensive devices and could quickly turn any carbon savings from ASHP operation into carbon emissions from air conditioning.
3.45 Legal technicalities are currently restricting ASHPs from being granted PDR in England & Wales. In England and Wales, the Government is now considering tackling this issue by stating the noise levels to which ASHPs should adhere to prevent annoyance or sleep disturbance to an average person, rather than setting a distance-based limit37. They have proposed various scenarios under which the installations of ASHPs are permitted or not permitted38. Given the similarities of the Scottish market with the rest of the UK, it should be kept in mind that vastly differing PD regimes could create barriers for manufacturers as well as confusion for consumers.
Summary of Key Findings for ASHPs
3.46 ASHPs can deliver significant carbon and cost savings when installed in a well insulated property and displacing certain fuels – typically grid electricity and solid fuel. Gas and oil systems tend to be more efficient than ASHPs and the case for replacement in these cases is marginal at best.
3.47 The main impacts of ASHPs from a planning standpoint are noise, vibration and visual. UK standards and best practices are in place to mitigate these factors under the Microgeneration Certification Scheme in conjunction with the appropriate British Standards (BS EN 14511). Further work is being carried out at the EU level on performance measurement under the Energy Using Product (EuP) Directive 2005/35/EC and the Energy Performance of Buildings Directive (EPDB).
3.48 In terms of PDR, consideration should be given to the operational characteristics of ASHPs where they can work in reverse as air conditioning units. In this mode of operation, the units become significant carbon emitters rather than a carbon reduction technology.
Microgeneration Certification Scheme and Microgeneration Installer Scheme
3.49 The Microgeneration Certification Scheme (MCS)39 was established by BERR, now the Department of Energy and Climate Change (DECC), in 2006.
3.50 The MCS is an independent scheme that certifies microgeneration products and installers in accordance with consistent transparent standards. It is designed to evaluate microgeneration products and installers against robust
37 http://www.communities.gov.uk/documents/planningandbuilding/pdf/319354.pdf P.21 38 http://www.communities.gov.uk/documents/planningandbuilding/pdf/564754.pdf 39 http://www.microgenerationcertification.org/
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criteria. The MCS therefore gives consumers a guarantee that MCS certified microgeneration products and the installers of those products have conformed to a rigorous set of standards.
3.51 The MCS is a third party certification process, which means there are a number of independent Certification Bodies that a manufacturer or installer can decide to certify with.
3.52 The MCS has support from the Department of Energy and Climate Change, industry and non-governmental groups, and although there are other proposed equivalent schemes it is currently the only accepted scheme whose products qualify for grants such as the Low Carbon Buildings Programme where both the microgeneration product and the installer must carry the MCS mark.
3.53 With regard to PDR the MCS standards are now examined for their ability to guarantee the microgeneration product, and to minimise or measure the impacts from both DWTs and ASHPs.
DWT Microgeneration Certification Scheme Product Standards
3.54 The development of micro wind turbines should be in line with MCS 010 “Generic Factory Production Control Requirements”40 which oversees 19 activities from quality management to purchasing and equipment. The final testing of the product will be in accordance with MCS acceptance criteria, including the requirement for “independent, third party, test laboratories” 41.
3.55 A product safety and function test should be conducted on the product in line with section 9.6 of the BS EN 61400-2:2006 guidelines. Product duration tests should be conducted under BS EN 61400-2:2006, section 9.4 specifications.
DWT Performance Standards & Certifications
3.56 Specific product performance and safety measurements outlined in the specific DWT MCS 006 will be undertaken in accordance with the British Wind Energy Association (BWEA) Small Wind Turbine Performance and Safety Standard42 which provides detailed and specific criteria outlined in the following section.
3.57 The public ‘Summary Report’ provided to a customer or installer for a particular MCS Certified DWT will contain:
• the power curve • the Average Energy Production (AEP) curve • the noise label • and the measured sound pressure levels (as per the standard).
40 BERR (2008) “Factory Production Control Requirements” http://www.greenbooklive.com/filelibrary/MCS_010_-_Iss_1_2_Factory_Production_Control_requirements_250208.pdf 41 BERR (2008) “Acceptance Criteria for Testing Required for Product Certification” http://www.greenbooklive.com/filelibrary/MCS_011_-_Iss_1_2_Microgeneration_Certification_Scheme_-_Testing_Acceptance_Criteria_250208_.pdf 42 BWEA (2007) “Small Wind Turbine Performance and Safety Standard” http://www.bwea.com/pdf/small/BWEA%20Small%20standard.pdf
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DWT Installer Standards
3.58 The “Microgeneration Installer Standard” (MIS 300343) sets out the criteria to deliver a DWT installation to the appropriate standard, and in accordance with the Energy Saving Trust report CE7244 “Installing small wind-powered electricity generating systems”. This takes into account siting, sizing and design criteria in line with the appropriate British Standards. Site specification issues will be dealt with by the inclusion of a site survey conducted by an industry professional. A sample survey is available in MIS 3003. This survey will determine site suitability, conditions and turbine performance potential.
Current MCS Standards Relating to DWT Impact Mitigation
Acoustic Noise
3.59 A noise mapping technique has been developed by the BWEA to predict DWT noise output and thereby allow installation of a DWT at a suitable location with an acceptable impact. The actual permitted noise levels would be set by the planning authorities. Figure 4 illustrates such a noise map.
3.60 To quantify the noise impacts, acoustic noise emission data is gathered simultaneously with wind speed in general accordance with BS EN 61400-11: 2003 but with the exception that the averaging period, t, for noise and wind speed data shall be at least t = 4*D seconds (where D is the DWT diameter expressed in metres) subject to a minimum period of 10s.
3.61 The wind-speed versus noise data covers a range from cut-in wind speed to 11.0m/s as a minimum, and the data should cover up to cut-out wind speeds if possible, particularly for turbines that have speed control mechanisms.
3.62 A Noise Slope is calculated from this series of measurements. At least 100 wind-speed noise data pairs shall be collected with data in valid sectors.
3.63 Data for the “Immission Noise Map“ are calculated over a range of wind speeds at rotor centre height and the map is plotted at levels of 40 and 45 dB(A) from the cut-in wind speed (minimum wind speed to produce mechanical movement) up to the cut-out wind speed (maximum wind speed before protective shut-down by braking, if applicable) for the given DWT.
3.64 The Declared Apparent Emission Sound Power Level LWd,8m/s (dB(A) re 10-
12W) is calculated using the approach of IEC 61400-14: 2005 from the reference noise immission characteristic for 8 m/s at the rotor centre height. This will be corrected for background noise (again from a linear regression of measurements) also for a rotor centre wind speed of 8 m/s.
43 BERR (2008) “Microgeneration Installation Standard” http://www.greenbooklive.com/filelibrary/MIS_3003_Issue_1_2_Micro_wind_25-02-08.pdf p.5 44 Energy Saving Trust (2004) “Installing small wind-powered electricity generating systems” http://www.energysavingtrust.org.uk/Global-Data/Publications/Installing-small-wind-powered-electricity-generating-systems-CE72
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3.65 The timescales over which the noise levels are measured vary appropriately depending on the scale of the turbine, but are as a minimum equivalent to dBLAeq 10secs which would cover all known frequency modes of dynamic noise from DWTs. In comparison, for example, to the 5 minute continuous integration time used for dBLAeq 5mins the noise map measurements may produce less of an averaging effect and are therefore more stringent.
3.66 The Character of the noise tonality, is also assessed. If the turbine is declared tonal, the Noise Label must show the Noise Penalty as “YES” and the penalty applied is 5 dB. The method as in BS EN 61400-11 can be used but the simpler method as in ISO 1996-2:2007 Annex D based only on 1/3rd octave band data is acceptable. The turbine is declared tonal if any 1/3rd octave band is higher than its adjacent bands by:
• 15 dB in the low frequency bands (50 to 125 Hz) • 8 dB in the mid-frequency bands (160 to 400 Hz) • 5 dB in the high frequency bands (500 to 10000 Hz).
Figure 4: Labelled Example of a BWEA MCS Noise Label
Source: BWEA Small Turbine Performance and Safety Standard 29th February 2008 3.67 Each MCS certified DWT must have undertaken an independent 3rd Party noise
quantification that produces the noise map specific to that DWT. This allows prediction and therefore limitation of acoustic noise for any given installation. Full details of the noise mapping techniques are specified in the BWEA, Small Wind Turbine Performance and Safety Standard, 29 Feb 200845. Appendix A of the same document provides a worked example of noise map application.
45 See http://www.bwea.com/pdf/small/BWEA_SWT_Standard_Feb2008.pdf
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Vibration, Visual, Natural Heritage, Built Heritage
3.68 There are no specific MIS standards unique to these, however the installer must have been assessed to be competent to cover a number of underpinning knowledge areas including the environmental impacts of wind turbines, specifically:
• proximity of proposed location to nearby residents and assessment of potential nuisance from noise or flicker
• details of listed buildings or if conservation area • ecology (e.g. impact on bats’ roost).
ASHP Product Standards
3.69 The Microgeneration Certification Standard for Heat Pumps (including ASHPs) is MCS 00746. The scheme provides ongoing independent, third party assessment and approval of companies who wish to demonstrate that their heat pumps meet the requirements of:
• EN 14511:2004 Parts 1 – 4 “Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling”47 to declare efficiency through rating and performance
• Demonstrating compliance through independent third party testing • Performance criteria set out in MCS 007.
3.70 Part 4 of the British Standard outlines product requirements, including the provision of technical data. In terms of monitoring the impacts of ASHPs, this standard calls for provision of sound characteristics (according to ENV 12102) but there are no requirements for the provision of vibration or visual mitigation at the manufacturing stage.
ASHP Performance Standards & Certifications
3.71 The relevant test standard for most packaged heat pumps is BS EN 14511-3 - “Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling” to declare efficiency through rating and performance48. For an air-to-water heat pump the standard specifies test conditions of 7oC outdoor air temperature (source temperature) and out/return flow temperatures of 45oC and 40oC respectively. Demonstration of compliance is through independent third party testing.
3.72 There is still a considerable lack of clear guidance and information to the consumer on how to compare and judge the energy performances of different makes of ASHP. The most commonly quoted performance data for ASHPs is the Coefficient of Performance (CoP). This is the amount of energy (heat) they
46 http://www.microgenerationcertification.org/docs/standards/MCS%20007%20-%20Issue%201.5%20Product%20Certification%20Scheme%20Requirements%20-%20Heat%20Pumps%2025%20Feb%2009.pdf 47 http://www.standardsdirect.org/standards/standards1/StandardsCatalogue24_view_11800.html 48 See http://www.standardsdirect.org/standards/standards1/StandardsCatalogue24_view_11800.html
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produce compared to the amount of energy (electricity) needed to run them. A typical CoP for an ASHP is around 2.549, but some manufacturers claim CoPs of up to 5.5. An energy rating standardisation, akin to the Seasonal Efficiency of Domestic Boilers in the UK (SEDBUK) rating for boilers, would be desirable for ASHP and this is being examined at EU level.
3.73 ASHP manufacturers and other stakeholders are currently working with the relevant governing bodies at EU level on new performance standards, specifically:
• The Energy Using Product (EuP) Directive 2005/35/EC50 - product focused and establishes a framework for the setting of eco-design requirements.
• The Energy Performance of Buildings Directive (EPDB) – system based to rate ASHP performance as part of building system energy performance.
ASHP Installer Standards
3.74 The Microgeneration Installer Standard (MIS) for ASHPs (MIS 300551) provides criteria for how each stage of the technology development is carried out including design, installation, commissioning and handover. In order to achieve accreditation, all requirements at each stage must be met. According to MIS 3005, the installation of ASHPs must always be in accordance with the manufacturer’s recommendations and materials should be in-line with criteria in the High Volume Air Conditioning (HVAC) publication “Guide to Good Practice – Heat Pumps”52. In addition, system performance should always be calculated and presented to the customer using the methodology set out in MIS 3005.
Current MCS Standards Relating to ASHP Impact Mitigation
Noise
3.75 The MCS (MCS 007) product test standards state that sound characteristics should be monitored in accordance with BS EN 12102 – 2008 “Air conditioners, liquid chilling packages, heat pumps and dehumidifiers with electrically driven compressors for space heating and cooling – Measurement of airborne noise – Determination of the sound power level”53.
3.76 The Microgeneration Installer Standard for ASHPs is MIS 300554 and sets out the following requirements for noise:
• The location of external fans, for example in air-source heat pumps, should be chosen to avoid nuisance to neighbours.
• Internal fans and ducts should be fitted with sound attenuation devices. 49 Energy Saving Trust, www.est.org.uk/Generate-your-own-energy/Air-source-heat-pumps 50 http://ec.europa.eu/enterprise/eco_design/directive_2005_32.pdf 51 See http://www.greenbooklive.com/filelibrary/MIS_3005_Issue_1_2_Heat_Pump_systems_25-02-08.pdf 52 HVAC “Guide to Good Practice – Heat Pumps [TR/30]” http://www.bsee.co.uk/news/fullstory.php/aid/4196/HVCA_launch_heat_pump_guide_.html 53 http://www.techstreet.com/cgi-bin/detail?product_id=1533206 54http://www.microgenerationcertification.org/docs/standards/MIS%203005%20Issue%201.5%20Heat%20Pump%20Systems%2025%20Feb%2009.pdf
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Vibration
3.77 There are no MCS standards unique to ASHPs for the provision of vibration mitigation. However, the general requirements state that the heat pump must meet the relevant test standards and the vibration characteristic should be monitored in accordance with BS EN 1736:2000 – ‘Refrigerating systems and heat pumps. Flexible pipe elements, vibration isolators and expansion joints. Requirements, design and installation’.
3.78 The MIS 3005 sets out the following requirements for vibration:
• Heat pumps should not be located adjacent to sleeping areas or on floors that can transmit vibration
• Anti-vibration pads/mats/mounts and flexible hose connections should be used to reduce the effects of vibration on the building structure.
Visual
3.79 The MIS 3005 sets out the following requirements for the location of ASHPs:
• Heat pumps should be located to the manufacturer’s instructions (in terms of health and safety, mounting, sufficient air-flow etc.)
• The suitability of a proposed heat pump installation site shall be assessed by qualified professionals experienced in heat pump systems. Where permissions, approvals and licences are required, the contractor shall ensure that these permissions and approvals have been obtained.
Summary of Key Findings for MCS and MIS Schemes
3.80 For both DWTs and ASHPs the MCS scheme has set down product criteria based on independent 3rd party evaluation to stated British and International Standards. These standards enable performance including the likely level of impacts to be measured and evaluated for any given installation.
3.81 Additionally the MIS scheme provides independent 3rd party evaluated accreditation for installers who utilise industry recognised Best Practice to install either DWTs or ASHPs.
3.82 The MCS scheme is Government (DECC) recognised and currently leads on providing UK standards. With regard to guaranteeing that PDR criteria are met, the MCS scheme is able to undertake such a role: both in terms of product functionality, and responsible installation.
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4 STAKEHOLDER CONSULTATION 4.1 Stakeholder consultation was central to identifying the issues surrounding the
adoption of PDR for DWTs and ASHPs. All Stakeholders were invited to submit their views and evidence by means of a written questionnaire and subsequent face to face discussions at two Stakeholder workshops.
Pre-workshop Questionnaire
4.2 The initial consultation methods (pre-workshop online survey and questionnaire available in the Appendices at page 58), were designed to highlight the key issues and themes that had already been deduced from the literature survey and previous Scottish Government consultation responses. All parties replying to the previous consultation, all local planning offices, environmental health officers, the associated manufacturers or trade organisations, all statutory consultees and many interested parties including technical experts in the fields of microgeneration technology were invited to respond.
4.3 The written responses (see Appendices at page 58) were summarised (refer to chapters 5 & 6) and the Stakeholder identified issues were used to develop the workshop discussion structure to formulate PDR recommendations.
Workshops
4.4 The Edinburgh and Aberdeen workshops took place at Scottish Government buildings on 31st August and 2nd September 2009 respectively. Each workshop followed the structure outlined in the above methodology, and the 5 break out groups were run identically. Both events were well attended and stakeholder feedback on the exercise was very positive.
4.5 The purpose of the workshops was to establish the main impact based issues relating to PDR for DWT and ASHP as identified by key stakeholders. The workshops provided the opportunity to interactively address the evidence and explore the qualitative issues surrounding PDR, allowing for a broader and more comprehensive debate. Further, the workshops provided a platform for stakeholders to voice any additional concerns or issues that had not been noted in the surveys or questionnaires.
4.6 Each workshop began with all attendees receiving a welcome from the Scottish Government followed by an introduction from SQWE, introducing the technologies and outlining the programme for the afternoon.
4.7 The large group of stakeholders was then split into smaller breakout groups with a maximum of 12 people. The breakout groups, facilitated by SQWE were composed to represent a balance of opinion (based on the survey and questionnaire responses) and an even representation from various stakeholder groups (e.g. planners and manufacturers). This representative cross-section of all pertinent issues within each workshop enabled all valid views to be critically discussed within a factual framework and helped to promote a ‘real-world’ workable outcome.
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4.8 Each workshop break-out group facilitator:
• Provided a welcome and appreciation to the stakeholders • Re-iterated the background brief with regard to PDR and the issues
stakeholders raised during the written response element of the consultation
• Reminded the stakeholders of the rules of engagement (e.g. evidence should be factual/quantifiable) and that areas unrelated to PDR would be off limits.
4.9 Two clearly structured and separate discussions per technology (DWT and ASHP) were undertaken in each breakout group.
4.10 The stakeholder discussion was structured so that:
• Each identified issue (e.g. noise; visual impact; vibration) was dealt with independently, initially without considering any coupling or cross-impacts to avoid unnecessary debate or irrelevant tangents. Any sub-issues were logged and dealt with as relevant to the identified issue.
• Discussion was managed to attempt to find consensus between the stakeholders as to what was an acceptable level of impact or a suitable mitigatory measure for the issue identified. For example noise was an identified issue: some stakeholders agreed that an acceptable level of noise impact at any dwelling could be 45dB(A) and the manufacturers indicated they would be willing to submit to certification that measures noise output and thus enables a DWT to be appropriately sited so as to meet the noise criteria.
• If consensus was not found, further factual clarification with regard to evidence for PDR criteria based on implementation of a precautionary principle was undertaken.
• After all the decoupled issues were dealt with, there was an opportunity to discuss cross-coupling of impacts and more general PDR issues.
4.11 The workshop concluded with all stakeholders rejoining one another to hear the closing remarks from SQWE and Scottish Government. These summarised the workshop responses, detailed the next stages of the project, and thanked the stakeholders for their invaluable inputs.
Conclusions
4.12 The written responses to the pre-workshop questionnaire provided a good evidence base to identify the issues to be discussed at the workshops.
4.13 The findings from the stakeholder consultation are presented in the following sections.
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5 FINDINGS: MICRO WIND TURBINES Noise
General
5.1 There was a general consensus from all workshops that noise from domestic wind turbines (DWTs) did have negative impacts on the surrounding areas, that noise was a “major hang up with neighbours and the public at large”, and that careful consideration should be made before permitted development can be applied.
“There is obviously an impact with noise, from the industry’s perspective it is absolutely important that we get this right, not just to allow business to flourish but to ensure that there is sufficient protection…it is absolutely not within the industry’s interest in the short term, long term, medium term, to allow turbines to be put up in the wrong place. We need to uphold consumer confidence in green technologies”.
5.2 Noise impacts are not an easy parameter to define because “different people have different tolerances and sensitivities towards noise…what one person would be tolerant of, another individual would not.”
5.3 The issue of noise nuisance was considered to be one of public perception. Regardless of whether the nuisance is unfounded or not, some consultees felt it did not eliminate the problem caused to planning and environmental health authorities.
5.4 Consultees debated the severity of wind turbine noise, with manufacturers claiming, that the turbines are not particularly noisy. This highlights an overarching theme reached in many of the workshops that there is insufficient wind turbine noise data available, as summed up by one comment:
“the problem with the planning process as far as wind turbines are concerned is the lack of decent noise data”.
5.5 It was agreed that the lack of data, case studies and planning guidance available to planners has resulted in a slow and problematic planning process. The planning system is considered to be
“bereft of detail specific guidance for wind turbines…so the planners have been put in a very difficult position on whether to give a green light, an amber light, or a red light to these projects”.
PDR must overcome these issues if it is to be successful. The BWEA DWT criteria were considered to be the closest to providing helpful noise guidance and limits, but the suitability of the limits remained a question to some.
Absolute or Locational Noise Limit
5.6 It was unanimously agreed across the workshops that a decibel based limit would be the most appropriate way to mitigate noise impacts. One consultee said that
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“when it comes to something like this that has planning implications, there needs to be a quantifiable element to it that we can benchmark [performance] against.”
There were however, conflicting views on the best way to apply this decibel limit; an absolute limit versus a location specific methodology (such as a noise rating curve). Options included:
• One absolute measure such as the WHO 45 dB • Implementing the use of a noise rating (NR) curve • Applying an absolute measure for typical scenarios and then implementing
an NR curve as a secondary measure in properties with very low ambient noise: “a bit more onerous but it will give a secondary phase for levels [in less straightforward areas, e.g. low ambient noise]”
5.7 Comments on the positives and negatives of an absolute limit versus a location specific methodology included:
• “a dB limit sounds sensible but the problem is ‘say you have a house with very close neighbours versus a rural location where there is no neighbour within two or three miles”
• “from an environmental health perspective, we would like to see any standard being (measured) from the closest neighbouring residential property to give an idea of the impact”
5.8 The purpose of permitted development was deemed to be to ease the development process and encourage uptake. Therefore monitoring and enforcement should be able to refer to straightforward quantitative guidelines.
Specific Noise Limits
5.9 Specific noise limits were a contentious issue with suggested day and night time limits ranging from 35-45 dB(A). One manufacturer stated that “we would generally go with the 35-45dB”. It was felt that it would be most appropriate to have a single limit rather than distinguish between day and night noise levels since “the noise doesn’t vary from these things night and day so you set it [the limit] for the worst case”.
5.10 Further questions arose over how to take into account those noise characteristics such as tonality since “it is not always simply a case of the decibel level” when it comes to noise nuisance. One suggested method for overcoming tonality was to apply a 5dB(A) penalty on noise levels, for products where tonality was identified as an issue. One participant was certainly “pleased to see that [the MCS] had included a tonal” penalty.
5.11 A mapping system (see Figure 4) was suggested as a means of aiding the installer, to determine areas where domestic wind turbines (for both noise and performance reasons) should absolutely not be installed. Similarly (although not to be used as an ultimate guide) they can indicate areas where a wind turbine may adhere to noise limits.
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5.12 A mapping system was described as a “sensible approach”: one participant stated that it would be helpful
“from an enforcement point of view if there are criteria there that make something [i.e. noise level] acceptable or not”.
5.13 The current MCS for products and MIS for installers was generally considered
to be a good standard from which PDR could be implemented. One manufacturer thought that “it should absolutely be done through the MCS…the more we can standardise this the better”. There were however, issues surrounding the onerous process of achieving accreditation, “PD is there to make it simpler… the more technical you make assessments for PD the harder it becomes”. While product and installers must be MCS or MIS accredited, it was agreed that there should still remain some customer responsibility during the installation to ensure that delivery meets expectations and specifications.
5.14 Further to the discussions on noise levels the British Wind Energy Association (BWEA) provided evidence sourced via a Freedom of Information (FOI) request to English Local Authorities which stated that of all the DWTs that had passed through planning less than 0.1% of 5500 micro-wind turbines, installed in the UK since 2005, have had noise complaints upheld.
5.15 Any noise limit must be robust enough to stand up to neighbourhood complaints and enquiries to noise abatement officers. If it is an approved installation, an enforcement order will be awkward.
5.16 A 3 year review would allow any noise limit to be re-examined in light of the experience and evidence gained during that period.
Vibration
5.17 The issue of vibration received very mixed responses during the workshops. While some felt vibration to be potentially as problematic as the noise issue, others stated that the issue was a small, non-technical one:
“generally, statistically the percentage of complaints that local authorities get about noise compared with vibration, vibration is way down it’s maybe 0.5-1% relative to 99% noise”.
As with domestic wind turbine noise data it was felt by the vast majority of stakeholders that there is “not sufficient vibration data” from which to draw necessary conclusions and recommendations.
5.18 There was a unanimous feeling that it is important to differentiate between free standing, and wall mounted turbines:
“vibration is only an issue for building or wall mounted units, for free standing units by the time you are 1metre away from it you are going to get nothing [in terms of vibration]”. There was a similar consensus differentiating detached and adjoining properties: since there “needs to be a lot more research …before you can predict how this type of turbine on this type of building will affect the structure.”
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The general feeling amongst consultees was that “until you have that kind of information I don’t think you should be allowing [installation] on multiple occupancy properties.” For the purpose of PDR, these differences will have to be taken into consideration, and the risks that vibration can have on property structure (and subsequent impacts on neighbours) will also have to address the vast variance in building fabric: where there are emerging significant impacts that are not clearly understood at present.
5.19 A forthcoming Defra study will look at vibration impacts but is not expected to make any judgements on what would be acceptable. The lack of current evidence makes it very difficult to set any sort of criteria and it was felt best to proceed with caution so as to avoid the potential situation where PD criteria are set, a lot of units are installed but later found to cause vibration damage.
5.20 Therefore, it was suggested on the principle that planning interventions are designed to minimise impacts for other people, that only detached houses should be eligible until there is more evidence on the vibration risks (although these were generally thought to be quite low). This would also help to protect the credibility of the technology from the set back of a technology being granted PDR which was subsequently removed.
Visual
5.21 It was unanimously agreed that “there obviously is an issue with visual impact” from domestic wind turbines (including cumulative impacts) but due to the subjectivity of such impacts the quantitative evidence is still a much contested issue. Some consultees reported that “it is a very emotive issue for some communities”. Perception is also an important issue in the context of visual impact:
“a lot of objections [arise] because of a perceived idea of what it will look like when it goes up” rather than the reality of what it actually looks like.
There was widespread acknowledgment of the difficulties of trying to “strike a balance” between performance, carbon reduction and the visual impact of turbines.
5.22 It was generally agreed that there should be a differentiation between building mounted and free standing turbines;
“2.2metre [rotor diameter is] ok for building mounted but when it comes to free standing we think it should be significantly [larger]…to actually get the performance.”
5.23 Ultimately it was noted that there is a trade-off between acceptable wind turbine size and acceptable energy performance, with many feeling that a rotor diameter of 2.2m should be the maximum size (“my first reaction was ‘that seems excessive, it seems a very large size”) and others feeling this “is the smallest practical size” or not of sufficient size to generate a worthwhile energy level. Manufacturers tended to feel an increase in diameter to 3.5m would
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generate disproportionately more power than one of 2.2m in comparison to the visual impacts.
5.24 A similar issue of visual impact versus performance benefit was also identified for determining a suitable turbine height limit. One consultee said that
“if you put the level of height too low, the consumer is not going to go through permitted development”
and would instead go down the planning permission route in order to ensure effective performance despite the additional burden of the planning process. It was generally agreed that the maximum for a building mounted turbine should be 3m above the highest part of the roof structure.
5.25 For a free standing turbine, 11.1m to the highest part of the DWT was considered too low by some consultees who felt that in rural areas there should be an
“increase in hub height…11metre is very low, just by increasing by a small percentage, you will be getting very large percentage increases and actually make the technology worthwhile.”
5.26 A limit of one free standing DWT per curtilage was generally agreed to be appropriate.
5.27 Colour was not considered to be a significant issue with one consultee summarising the feeling that
“generally you wouldn’t be that prescriptive of colour, you would say that as long as it is as unobtrusive as possible that would be it: you wouldn’t specify a colour”. However another consultee felt that there “has to be some sort of control” over colour, with some planners suggested a matt, light grey, to be the most subtle colour.
5.28 More generally some stakeholders noted that “context” is important so one absolute rule may not be appropriate. For example a free standing DWT rotor probably doesn’t look too different at 2.2 or 3.5 metres diameter, but clearly this would be very different if it was building mounted.
Electro-Magnetic Interference (EMI)
5.29 “There may also be a risk of interference with radar systems/air traffic control for the larger freestanding turbines”. However a Planning Authority Stakeholder responded evidentially that currently the Ministry of Defence (MoD) and the Civil Aviation Authority (CAA) both require notification and approval of any wind turbine in the UK, including all DWTs. This issue could be outside of any PDR, but a certified installer would be required to meet such obligations.
Flicker
5.30 The issue of shadow and reflective flicker was considered underrepresented by some planners who felt that this should be an important factor in setting PDR conditions. It was thought that the fairest way to monitor this would be through installer responsibility, perhaps by the inclusion of flicker in the MIS guidance.
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Built Heritage
5.31 There was considerable agreement that PDR should not extend to areas designated on grounds of built heritage – including within the curtilage of a listed building. A planning stakeholder stated that although
“there is potentially less risk of detriment from a stand alone one, I still think stand alone wind turbines in a conservation areas could quite significantly impact upon the character of the conservation area” in question. Therefore generally neither building mounted nor stand alone units were deemed appropriate for listed buildings, Conservation Areas or World Heritage Sites. Suggestions were made for allowing installation of DWT in these areas through planning permission. One consultee explained that if “you don’t have PD rights and... if you have to apply for planning permission and the only reason they have to apply is because of that restriction, [you] won’t have to pay the planning fee”.
5.32 If PDR is granted, some consultees felt schools should be considered separately on the grounds of health and safety. This was however noted as being a health and safety issue rather than a planning issue.
Natural Heritage
5.33 Again, it was generally agreed that PDR should extend to areas designated on grounds of natural heritage as to date there was no specific evidence of negative impacts.
5.34 For those that felt PDR should be given in areas of natural heritage, it was considered that common sense and adoption of good practice in terms of sensitive locations (e.g. areas known for birds, bats, or breeding sites) should suffice to protect these areas. This could fall under the responsibility of the installer. Another option would be to establish a monitoring period whereby:
“there is plenty of other legislation out there to protect them [birds & bats] and if new data has come through in three years time lets review that then.”
3 Year review
5.35 It was generally agreed that a periodic review, at a maximum of every 3 years, would be appropriate to evaluate the suitability of PDR. One consultee stated:
“I think that the three year review idea is a brilliant one...to look at the whole issue again in three years time, see how successful it has been and also to see any difficulties brought up by it.”
5.36 A central database would allow for any issues to be recorded and to determine the uptake of these technologies or impacts. Any unintended consequences of DWT that had not been foreseen in the current PDR process could be addressed during such reviews.
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Prior Notification
5.37 It was suggested by stakeholders that prior notification may be an option for the installation of DWTs. Given a notification period of 28 days if no planning objections are forthcoming, the DWT could then be granted PDR. It was felt that this could be particularly useful since
“we are not really recording how many of these technologies we are actually putting up, there is an onus on councils to be promoting green energy and green technologies but with all the PD we have no way of knowing how many we have got.”
Although prior notification could help to build up a picture of the microgeneration actually installed it was noted that it does not lead to neighbour notification.
Promoting Simplicity
5.38 It was noted in all the stakeholder workshops that it is important that it is not too difficult for planners to explain PDR to the public; they will have
“to produce a piece of guidance… something that when someone turns up and says ‘do I need planning permission for this turbine’ you’ve got a list… almost a tick box exercise, have you got this? Have you been here? Have you done that?”
5.39 Issues will occur surrounding the capability of the planning system to help with regard to PDR:
“It is going to be difficult for a helpdesk planner to explain all of this to the public.”
and “We need to provide a guidance list that is clear and succinct.”
Impact Matrix Summarising Key Points
5.40 The following matrix (Table 11) lists the stakeholder identified issues, the proposed acceptable level of impact, and any possible mitigatory measures.
Table 11: Impact Matrix for DWT Issue Description
of Impact Evidence of impact from DWTs to date
Acceptable Impact Level
Mitigation Recommendation
Noise (aerodynamic and mechanical)
Noise causing an unlawful interference with a person's use or enjoyment of their amenity.
A small number of upheld complaints
WHO recommended internal room noise level of 30dB(A) and external noise level of 45dB(A)
Reduce the DWT noise level to meet noise criteria. This may be by product design or installation design - i.e. suitable distance of device from receiver
Adopt a suitable maximum noise level, i.e. 30dB(A) internal, equating to 45dB(A) external or garden. A 5dB(A) penalty would be added if tonality was present in the noise.
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Guarantee these noise levels by use of a product and installer certification scheme. For example the MCS noise mapping methodology.
Vibration Vibration of building fabric and annoyance of occupants
A small number of complaints leading to shut-down of DWT until modifications could be undertaken
Unknown – research is underway by DEFRA.
Installation according to manufacturers installation standards with use of anti-vibration mounts on suitable properties
That accredited installers will ensure that only MCS certified DWTs are installed to best practice on detached properties.
Visual Reduction in visual amenity to the public
A small number of complaints: often pre-installation
Highly subjective but generally taken to be acceptable when a DWT or DWTs do not become a dominant feature in a landscape or setting
Suitable size and height of turbines related to their setting
Building mounted DWTs of less than 2.2m diameter and 3m maximum height above roof ridge are PDR. PDR for stand-alone DWTs of 2.2m maximum diameter and maximum height of 11.1m unless greater than 100m from a neighbours curtilage in which case diameter may be 3.5m.
Shadow Flicker Nuisance and upset to humans. Possible trigger for photosensitive epileptic seizures
A very small number of complaints In a statement Epilepsy Action “does not challenge the theory that wind turbines may create circumstances where photosensitive
In Germany shadow flicker has been taken to be legally unacceptable if it occurs for more than 30 hours per annum.
Suitable positioning of a DWT away from neighbouring properties
It was thought that the noise limitations will introduce a distance from neighbouring properties that will negate this effect, but MIS will implement best practice to avoid this.
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seizures can be triggered.” “However from our experience and that of our members and website users it does appear that this risk is minimal.”55
Natural Heritage
Negative impacts on flora and fauna
None but possible bird and bat impacts
None Care in the siting and installation of DWTs to avoid natural heritage impacts
Re-examine evidence with a 3 year review
Built Heritage Reduction of amenity or value within a setting
A small number of complaints
Subjective but generally taken to be acceptable when a DWT or DWTs do not dominate or detract from the built heritage
Avoidance of sensitive areas of built heritage
PDR would not be extended to the curtilage of Listed Buildings, Conservation Areas or World Heritage Sites Stand alone DWTs should not face onto and be visible from the highway in Conservation Areas or World Heritage Sites
Electromagnetic Interference (EMI)
Radiated EMI observed on other receiving devices OR received signals degraded/ attenuated
None at DWT scale. (Significant with large utility scale wind turbines)
None Avoidance of EMI sensitive areas such as aerodrome or defence radars.
Product Standards guarantee compliance with regard to radiated EMI. PDR does not over-ride the necessity to inform the Civil Aviation Authority of all DWTs – this is therefore a general condition that the certified installer would be aware of and seek permission for.
Source: SQW Energy
55 Epilepsy Action in association with Professor Graham Harding http://www.epilepsy.org.uk/campaigns/survey/windturbines
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6 FINDINGS: AIR SOURCE HEAT PUMPS Noise
6.1 Although considered to be less of a noise nuisance than DWTs, ASHPs should be given a noise limit to prevent unnecessary noise complaints:
“noise is definitely a potential impact; we’ve had noise complaints about an ASHP.”
For ASHPs, it was noted by one consultee that: “noise is the most significant issue”.
This was backed up by the comments of another consultee who stated that: “when we have gone to planning the two things have been: tell us about the noise and can you make sure it is to the rear of the property”.
6.2 Some noise data was quoted during the consultations with typical noise levels “about 59-65dB at the unit, and as you move away from it they drop quite considerably to typically 36dB at 10m”.
As the technology becomes more popular, data will need to become available to customers, manufacturers and installers.
6.3 Regardless of the noise limit, many feel measurements need to be conducted in a standardised way and that there does need to be “a black and white criteria”. Noise Rating (NR) curves56 and noise mapping were considered to be useful tools to manage noise levels of ASHPs. Some consultees noted that the fan frequency level should be considered alongside the sound pressure as “another component that can cause annoyance is the tonal aspect of the sound”.
For this reason, NR curves found considerable support: “we assess the noise from these [ASHP units] in a slightly different way; we use noise rating curves for fan type equipment. NR curves are a frequency based measurement which are different from data you have from manufacturers.”
6.4 In Edinburgh many tenement licenses for air conditioners (ACs) are dealt with by NR25 Noise Condition, but also planning permission. The limit under NR25 is 40dB in the nearest adjacent house with the windows open.
“helpful from an enforcement point of view if there are criteria there that make something [noise level] acceptable or not before installation”.
56 Noise rating (NR) is a graphical method for assigning a single number rating to a noise spectrum. Annex B of BS 8233:1999 discusses the use of NR curves and provides a method of calculating NR values. NR curves can be used to evaluate a wide range of noise sources in both indoor and outdoor situations and are particularly useful for dealing with noise from fans, ventilation and air conditioning systems. (See Noise and Man, Burns: 1975, pl48-155.)
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6.5 It seemed inappropriate to grant different noise limits for different technologies, so those who agreed with a World Health Organisation (WHO) noise level for DWT tended to agreed with a WHO level for ASHPs. However it was recognised
“that this is fine in an urban area but…could still cause a problem in a very quite rural area so what we have done is knocked off 5dB off each of those [day and night] standards”.
6.6 Further comments with regard to actual experience with ASHPs included: “almost unaware when it [ASHP unit] was switched on”
“from the ones I’ve seen in operation, I wouldn’t be bothered about it sitting outside the bedroom window”
“noise doesn’t seem to be significantly different from what could be put in for other domestic appliances”
6.7 The Microgeneration Certification Scheme (MCS) was considered to be an appropriate structure for ASHP noise limits, and responsibility should fall with the manufacturer and installer:
“by placing a level of ‘at 1m distance that machine should hit a level of x [dB]’ forces the manufacturers to innovate and attenuate the noise better.”
PDR should only be granted to those who use MCS accredited products and installers with one consultee stating that: “the three things that would qualify an ASHP installation for PD are product certification…installer certification…and thirdly that sound level [limits] apply”.
6.8 MCS will ensure traceability and transparency. It was suggested that the definition of noise level is important and should be set on sound power level to remove the issue around the subjectivity with relation to what constitutes noise nuisance.
Vibration
6.9 Overall it was thought that compared to noise “vibration will be a very, very small element”,
but it was recommended that “some sort of mitigation or isolation is put in place for vibration against the structure” in areas where neighbours are affected by the vibratory effects. Installers can mitigate these effects if the location of the ASHP is carefully considered. Ground mounted ASHPs will have far less of an impact than wall mounted fixtures and therefore special considerations must be made for adjoining properties.
6.10 There was some discussion around the vibration impacts in flats compared to houses but it was suggested that PDR be given as long as there was no
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vibration impact on adjacent flats or properties. It would be the responsibility of the installer to ensure that there was no vibration at adjacent properties.
Visual
6.11 Generally it was considered that the visual impacts of ASHPs are minimal. One consultee said
“I don’t think a large one would have that large a visual impact”. Primary considerations should be made for neighbour perception, but this perception should be in line with that of wheeled-bins and other street furniture and therefore should not cause too much problem since ASHP units are
“just one of those things you find within a garden…it is accepted.” 6.12 For those who felt ASHPs created a significant visual problem, generally
avoiding front/rear and highway facing installation should minimise any visual problems:
“on the back of a house, facing a garden, fine. On the side of a house, no, visible from the street, no”, “as long as it is not on a principal elevation then let them get on with it” “generally people would do that anyway”
6.13 Further, regular reviews of the PDR process could quickly determine whether visual impacts (including cumulative impacts) were indeed a significant problem:
“I think if we know we are coming back in three years time to review this given more evidence…rather than carte blanche give it to everything, I would rather see it on attached and detached houses, hold off from flats and review it in three years.”
This view was widely supported with specific comments including: “I would have reservations about having either of these technologies on a flat” and “in terms of flats or apartments, I wouldn’t put either of these [technologies] on them at the moment”.
6.14 A number of stakeholders alluded to the fact that there is still 60% of housing stock in Scotland that is not ‘flatted’, and data collected during the next 3 years could provide evidence of feasibility before any review.
6.15 There was little concern regarding the colour of ASHPs, with one consultee stating that
“if visual intrusion is not a problem anyway, then I don’t think it matters what the colour is”
Built Heritage
6.16 Generally it was agreed that built heritage areas should not have PDR but as with DWT, there might be a case for a reduced fee for the planning application.
6.17 Some consultees however thought that if air conditioners (AC) are acceptable in heritage areas then there should not be an issue for ASHPs:
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“we certainly allow air conditioning units in World Heritage sites so we would be a bit daft if we stopped them [ASHPs] as well”
Natural Heritage
6.18 No natural heritage issues were identified for ASHPs.
Other Issues
Reverse Operation
6.19 Scottish demand for AC use is expected to be low.
Performance
6.20 While performance was accepted as being important, it was also considered that
“it is not a planning issue, it is a product certification issue” and therefore should not be taken into consideration for PDR.
3 Year Review
6.21 A 3 year review is deemed appropriate to monitor the progress of ASHPs and any impacts should they be granted PDR.
Prior Notification
6.22 It was suggested that prior notification may be an option for the installation of ASHPs. Given a notification period of 28 days, the ASHP could then be assumed to be a PD.
Impact Matrix Summarising Key Points
6.23 The following matrix (Table 12) lists the stakeholder identified issues, the suitable level of impact and the proposed mitigatory measures.
Table 12: Impact Matrix for ASHP Based on Stakeholder Responses Issue Description Evidence of
Impacts Acceptable Impact Level
Mitigation PD Criteria Recommendations
Noise Acoustic noise nuisance - generally to neighbours
Small number of noise complaints dealt with by environmental health officers
Use of NR curves: NR25 or NR 30 viewed as suitable internal room measure. WHO recommended internal room noise level of
Reduce the ASHP noise level to meet noise criteria. This may be by product design or installation design
Adopt a suitable maximum noise level, i.e. 30dB(A) internal, equating to 45dB(A) external or garden. A 5dB(A) penalty would be added if tonality was present in the noise.
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30dB(A). Guarantee these noise levels by use of a product and installer certification scheme.
Vibration Vibration transmitted through building fabric causes annoyance
No specific evidence, but possibility if incorrectly installed
Unknown Installation according to reputable manufacturers installation standards with use of mechanical solution such as isolation anti-vibration mounts
That accredited installers will ensure that only MCS certified ASHPs are installed to best practice.
Visual and Built Heritage
Negative impacts on setting and landscape
Similar installations such as AC require planning permission
Not to be visible from public areas
Avoiding front and highway facing installations
PD if ASHP not placed on the principal elevation facing onto and visible from a highway in buildings in Conservation Areas Not PD at World Heritage Sites.
Natural Heritage
Negative impacts on flora and fauna
None Not applicable Not applicable Examine evidence emerging from a 3 year review
Electromagnetic Interference
Radiated EMI observed on other receiving devices OR received signals degraded/ attenuated
None Not applicable No applicable Product Standards already guarantee compliance
Air Quality Odour or pollution
None Not applicable Not applicable Product Standards guarantee compliance
Source: SQW Energy
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7 ASSESSMENT OF PERMITTED DEVELOPMENT OPTIONS This section utilises the previously reported Stakeholder evidence and literature review findings to outline the possible PDR conditions or criteria for DWTs and ASHPs. PDR Principles
7.1 In order to develop possible PDR conditions the regime specifications should aim to be:
• Clear and comprehensible – eases consumer understanding and allows consistent interpretation and advice from planners to developers
• Simple – to remove inconsistencies between different categories of PDR or in this case to differing subclasses (technologies) and the limitations which apply to them
• Non burdensome – any PDR conditions should not be more burdensome on the developer, planner or other entity than those preceding the granting of PDR.
In addition two further principles were deemed desirable:
• Any PDR regime or condition should be blind to an installation’s commercial potential as this evaluation lies outside of the planning system and would be unenforceable
• Any PDR conditions should where possible be neutral to technology development or improvement and based on measurable and practical impact attributes.
PDR Conditions for a Specific Noise Criterion
7.2 The impact approach agreed by all stakeholders necessitates that an appropriate and specific noise level based on sound science and equivalent for both technologies is identified.
7.3 Although Scotland is not included in the Noise Act 1996, there is capacity to deal with issues of noise through statute or common law57. However, a problem arises when trying to quantify the issue of noise as “there is no objectively measured level at which nuisance does, or does not exist”58. Instead cases are dealt with individually and are subjectively monitored.
7.4 There is however some guidance on acceptable noise limits and a number of respected studies and methodologies to identify an appropriate noise impact levels are now reviewed.
57 Scottish Executive (2004) “The feasibility of introducing in Scotland an absolute objectively measured permitted noise level which if breached during any time of the day would cause an offence liable to conviction” http://www.scotland.gov.uk/Resource/Doc/930/0010373.pdf p.24 58 Scottish Executive (2004) “The feasibility of introducing in Scotland an absolute objectively measured permitted noise level which if breached during any time of the day would cause an offence liable to conviction” http://www.scotland.gov.uk/Resource/Doc/930/0010373.pdf p.24
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7.5 Table 13 describes some typical NR curve applications. An NR curve allows different maximum sound pressure levels (dB) to be plotted at different frequencies.
Figure 5: Examples of Noise Rating (NR) Curves
Source: Industrial Acoustics Company "Noise Control Reference Handbook" Table 13: Comparison of Noise Rating and dB(A) Type of Room - Occupancy Noise Rating (NR) Concert halls, recording studios, theatres etc. 20Private bedrooms, live theatres, television and radio studios, lecture rooms, cathedrals and large churches, libraries, etc.
25
Private living rooms, board rooms, hotel bedrooms, etc. 30Public hotel rooms, small offices, classrooms, courtrooms, etc. 35Source: SQW Energy 7.6 The Wilson Report59 advised noise categories where the strictest level is
40dBLA10(T) during the day and 30dB LA10(T) inside habitable rooms.
7.7 The World Health Organisation (WHO) published a set of guidelines summarised in Figure 6 for community noise60 that suggest
59 Wilson Report, Committee on the Problem of Noise. (1963) Final Report. Cmnd. 2056. HMSO.
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“If negative effects on sleep are to be avoided the equivalent sound pressure level should not exceed 30dB(A) indoors for continuous noise. If the noise is not continuous sleep disturbance correlates best with LAmax and effects have been observed at 45 dB or less. This is particularly true if the background level is low. Noise events exceeding 45dB(A) should therefore be limited if possible. For sensitive people an even lower limit would be preferred. It should be noted that it should be possible to sleep with a bedroom window slightly open (a reduction from outside to inside of 15 dB).“
Figure 6: WHO Guidelines for Community Noise
Source: WHO 1999 7.8 Figure 7 outlines recommended internal noise levels reported by the Robin
Mackenzie Partnership for Scottish Building Standards on building services noise61.
Figure 7: RMP suggested building services (internal) noise criteria
Source: RMP Acoustics, Services noise affecting dwellings, December 2007 Recommendation 7.9 We recommend that the PDR noise conditions for both DWT and ASHPs
require that the noise emitted by the installation should not be received at a level exceeding 45dB(A) at the curtilage of any neighbouring property; and
60 WHO Guidelines for Community Noise (Preservation of sleep: P26-28): http://whqlibdoc.who.int/hq/1999/a68672.pdf 61 RMP Acoustics, Services noise affecting dwellings, December 2007 http://www.sbsa.gov.uk/research/summ_service_noise_dwelling.htm
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would not exceed 30dB(A) inside a room in which persons might reasonably be expected to sleep62. As recommended in the literature, a 5dB(A) penalty should be applied to the measured noise power if impulsive or tonal characteristics are present.
Justification 7.10 The absolute exterior noise limit (sound pressure level) has been set in line
with current guidelines (WHO, RMP and Wilson Report) to produce an acceptable interior noise level that we believe will protect amenity while accommodating DWT and ASHP.
7.11 Although it is the interior noise level that is most likely to cause a nuisance, there is no practical way of being able to measure the background level within a neighbouring property without permission and a costly survey – both of which are not viewed as being in the spirit of PDR. NR curves are therefore not an appropriately simple measure on which to base a noise level.
7.12 The setting of an absolute noise level also meets the technology neutral requirement and allows improvements in product with regard to noise emission.
Vibration – DWTs and ASHPs
7.13 Vibration impacts are difficult to predict or measure and there is no accepted level of nuisance. Stand-alone units are unlikely to produce vibration nuisance, however building mounted units must be installed with appropriate vibration attenuation mountings and isolation.
Recommendation 7.14 Building regulations are concerned with vibration in so far as they may impact
on structures; however, there should be a general condition requiring that installation of either DWT or ASHP should be by a certified installer who will comply with the same.
7.15 A general condition should therefore be inserted of 'not causing loss of amenity by vibration’ for ASHPs, and a specific condition that PDR for DWTs should only apply to detached properties.
Justification 7.16 The proposed condition on vibration will allow best practice to be implemented
by a certified installer thus removing the burden on both the householder and the planning authority.
7.17 There is much experience with the damping of vibration from AC units which are similar to ASHPs and the industry is well able to provide vibration limitation at any installation.
62 The 30dB(A) internal limit takes into account the well established 15dB(A) attenuation of sound through a wall and partially open window to allow reasonable ventilation.
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7.18 DWTs have been found to produce significant vibration and the industry is still learning how best to attenuate these impacts under all circumstances.
Adoption of the MCS and Microgeneration Installers Scheme (MIS) Standards
7.19 The Microgeneration Certification Scheme (MCS) is an independent scheme that certifies microgeneration products and installers in accordance with consistent standards. It is designed to evaluate microgeneration products and installers against robust criteria providing greater protection for consumers.
7.20 The MCS has support from the Department of Energy and Climate Change, industry and non-governmental groups, but there are other proposed schemes.
7.21 The MCS product standard for DWT (MCS006) specifies that a DWT must comply with the British Wind Energy Association Small Wind Turbine Performance and Safety Standard. This in turn and specifically with regard to PDR allows quantification of noise and produces a scientific noise mapping system so that MIS certified installers can install a DWT to meet the set PDR noise limits. Additionally this standard provides best practice guidelines for installers with respect to minimising impacts such as vibration, visual impact, natural heritage etc. The MCS can incorporate any required PDR parameters within its revision programme.
7.22 The MCS product standard for ASHP (MCS007) specifies the standards to which a Heat Pump must comply. Again systematic methods for noise and vibration quantification are outlined. An additional useful feature would be to provide a noise label on all approved ASHPs which would outline that products noise power level dB(A) at a distance of 1m under standard test conditions from which installed noise levels could then be evaluated. In exactly the same manner as with DWTs there would be an additional 5dB(A) penalty for tonality.
Recommendation 7.23 That the MCS and MIS standards (or a directly equivalent Government
approved standard) for DWTs be adopted as the basis for guaranteeing that PDR conditions are met. The current MCS product standard (MCS006) is regarded as sufficient.
7.24 That the MCS and MIS standards (or a directly equivalent Government approved standard) for ASHPs be adopted as the basis for guaranteeing that PDR conditions are met. The current MCS product standard (MCS007) with the addition of a noise label to allow correct installation of the ASHP according to the PDR conditions would be regarded as acceptable.
Justification 7.25 The impact criteria set by the PDR conditions require a guaranteed standard in
terms of DWT or ASHP performance and appropriate installation to best practice. The MCS or equivalent provides this guarantee.
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Visual Impact: Building Mounted DWTs
7.26 No stakeholder indication firmly or evidentially suggested that a 2.2m diameter and 3m above roof height are unsuitable. Although a diameter limit is appropriate for a horizontal axis wind turbine, it is not for a vertical axis wind turbine and a rotor swept area would be a suitable measure.
Recommendation 7.27 Building mounted DWTs of no greater than 2.2m (or a swept area of less than
3.8 square meters), with no part of the wind turbine or associated structure being at a height of more than 3m above the roof ridge receive PDR.
Justification 7.28 Although visually significant within a building’s curtilage, this scale of DWT is
unlikely to be a dominant feature to a large area or population. Additionally the likely forces exerted on a building by such a turbine are large: any further increase in the allowed sizing or height rapidly increasing the requirement for major building reinforcement.
Visual Impact: Stand-alone DWTs
7.29 Few stakeholders suggested that a 2.2m diameter and 11.1m maximum height are unsuitable in urban areas.
7.30 Additionally it was deemed wise to set a minimum buffer of the DWT topple height from a neighbouring curtilage, i.e. 11.1m.
7.31 The trade-off between DWT diameter and visual impact is difficult to empirically assess, however a suggestion was made that a 3.5m diameter could be allowable if the installation is over 100m from a neighbouring curtilage.
7.32 Utilising the Carbon Trust Wind Yield Estimation tool63 it is notable that in most cases an increase in maximum DWT height from 11.1m to 15m produces an approximate 33% energy increase.
Recommendation 7.33 A stand-alone DWT at a distance of less than 100m from a neighbour’s
curtilage whose diameter is equal to or less than 2.2m (swept area equal to or less than 3.8m2) and whose maximum height is less than 11.1m will receive PDR.
7.34 A stand-alone DWT at a distance greater than 100m from a neighbour’s curtilage whose diameter is equal to or less than 3.5m (swept area less than or equal to 9.6m2) and whose maximum height is no greater than 11.1m will receive PDR.
63 Available at: http://www.carbontrust.co.uk/publicsites/wpestimator/default.aspx
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Justification 7.35 The larger 3.5m diameter acceptable at a 100m distance would effectively limit
such an installation to rural areas where the larger diameter DWT’s visual impact is likely to be a lesser element within the setting. An increased DWT diameter from 2.2m to 3.5m increases energy capture by a very significant 250%.
7.36 An increase in maximum height beyond 11.1m would allow some improvement in energy capture, however various statutory stakeholders would require further evaluation at greater heights.
Appropriate Number of DWTs per Curtilage
Recommendation 7.37 That 1 DWT may be installed per curtilage under PD. This applies to both
building mounted and stand-alone DWTs.
Justification 7.38 The cumulative impacts (visual, noise, vibration) of multi-turbine projects are
not well understood and further experience should be gained before implementing PDR for such installations.
7.39 Additionally the costs of planning permission are a proportionately lower cost per turbine for multi-turbine projects and are thus not viewed as a major barrier to implementation.
Visual Impact – ASHPs
7.40 ASHPs are not deemed by stakeholders to present a significant visual impact risk in most envisaged installations.
Recommendation 7.41 ASHPs should receive PDR subject to generic limits such that the equipment is
sited to minimise its effect on the external appearance of the building and the amenity of the area. PDR should also include specific measures for areas of Built Heritage which are outlined separately below.
Justification 7.42 The limits set are equivalent to those for similar installations (such as air-
conditioning units).
Aircraft Safety – DWTs
7.43 Aircraft safety is paramount and any interference of radar (including Defence Estates) and navigation systems from DWTs would be unacceptable. It is however, noted that there is no known published evidence of DWTs impacting such operations, indeed yacht mounted wind turbine systems may often be placed adjacent to radar scanners without system compromise.
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Recommendation 7.44 The work underway to develop a website whereby a certified installer can
ascertain if an MCS or equivalent certified product may be erected at a specific location without conflicting aircraft safety should be extended to Scotland and formalised with the CAA and Defence Estates. The requirement to carry out this safety check should be enshrined within any installer certification scheme, and only certified installer DWT developments would receive PDR.
Justification 7.45 Setting PDR conditions to overcome this issue would be problematic and
complicated. The responsibility is therefore put on the certified installer, without whom PDR would not be granted.
Natural Heritage and Landscape Impacts – DWTs Only
7.46 Little evidence of impacts on flora or fauna was forthcoming at this stage of DWT development.
7.47 Scottish Natural Heritage (SNH) should be consulted on all proposals within National Scenic Areas and Areas of Great Landscape Value where the height of the turbine(s) exceed 12m (to blade tip) as recommended in Scottish Government Planning Circular 9/1987.
Recommendation 7.48 PDR should be extended to National Scenic Areas and Areas of Great
Landscape Value as the size limits (i.e. maximum height of 11.1m) are currently below those requiring statutory consultation with SNH.
7.49 PDR should not be extended to SSSIs and Sites of Archaeological Interest by the precautionary principle, particularly with relation to possible impacts on of DWT foundations on areas designated for their geology or archaeology.
7.50 Other areas outside of those denoted above would receive PDR with the general condition that all reasonable precautions are observed in terms of installation of micro turbines. We advise that existing best practice is implemented through the MIS, for example, that DWTs should be located away from regular nest sites and that installation of micro turbines is avoided during the breeding season.
7.51 As further impact evidence may become apparent with increasing numbers of installations, a 3-Year review is recommended to re-assess any new evidence.
Justification 7.52 There is little evidence of significant impacts on wildlife, and areas of landscape
value are not considered to be at significant risk as the scale of the proposed developments are generally of a very small size compared to the scale of protected landscape element.
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7.53 The size limits proposed above constrain impacts of developments to what are believed to be acceptably low levels. Separate required consent regimes, such as possible Environmental Impact Assessment (EIA) Regulations, Habitats Regulations and the Controlled Activities Regulations impose further safeguards that installers must be aware of and adhere to.
Built Heritage
Recommendation 7.54 PDR should not apply to installations within the curtilage of Listed Buildings
which are themselves already protected by Listed Building Consent (LBC) legislation.
7.55 In conservation areas, PDR for DWTs would not be granted as the installation could adversely affect the character and setting.
7.56 In conservation areas, PDR for ASHPs would exist if the ASHP is not on an elevation facing a public way (whether or not it is attached to that elevation).
7.57 World Heritage Sites are deemed very sensitive to any development. The key concern is protecting the ‘Outstanding Universal Value’, and thus PDR will not be extended to World Heritage Sites for either DWT or ASHP.
Justification 7.58 Listed Building Consent (LBC) is required should the DWT or ASHP alter the
character of a listed building and is fixed to it or to a structure within its curtilage. New free-standing structures are therefore a matter for planning permission alone and that is why allowance is made for the curtilage of listed buildings, but not listed buildings themselves. Not granting PDR to the curtilage of Listed Buildings allows the planning authority (and Historic Scotland in the case of an A listed building) to assess if it impacts on the setting.
7.59 The proposals for Conservation Areas and World Heritage Sites were deemed appropriate by stakeholders to mitigate unnecessary impact on built heritage.
General Recommendations Surrounding PDR for ASHP and DWT
A number of general recommendations were made during the Stakeholder Consultation and each is summarised below with a recommendation. Prior Notification
7.60 Prior Notification (PN) was suggested as a means by which it would be possible to check that an ASHP or DWT installation would take into account all necessary checks, legislation and best practice guidelines. Additionally PN could provide a database of DWT and ASHP installations, particularly with regard to keeping a record of any impacts reported and technology uptake.
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Recommendation 7.61 Prior notification should not be used to undertake this function. Installation in
line with all guidelines and relevant legislation (e.g. health and safety, MOD, CAA etc.) should be the responsibility of the accredited installer. A possible installation database as a part of the MIS scheme could be utilised instead.
Justification 7.62 Prior Notification is viewed as an additional burden on the planning system and
therefore does not meet one of the criteria for an efficient PDR regime. The functions relating to health and safety or a specified third party interest (Building Standards, CAA etc.) restrictions are outside of the scope of PDR.
3 Year Review of Permitted Development Rights
7.63 Although there has been a rapid expansion in the demand and supply of both DWTs and ASHPs, experience is still being gained with regard to possible impacts. The proposals for PDR set out in this research have been based on the most recent and best available evidence. However it is foreseen that increasing installations may bring further evidence as to the suitability of the proposed PDR Regime for DWTs and ASHPs.
7.64 To maintain consumer confidence the 3-year Review should not be retrospective with regard to installations already granted PDR.
Recommendation 7.65 In order to take account of the likely increased experience and learning a 3
Year Review of the PDR regime for DWT and ASHP is recommended.
Justification 7.66 A 3-Year Review would allow any future learning particularly with regard to the
impacts and MIS scheme to be evaluated and incorporated.
Anemometers for DWT
7.67 During the research it became apparent that anemometers associated with verifying the site suitability for DWTs often require planning permission.
Recommendation 7.68 A temporary anemometer associated with DWT and no higher than the
maximum height of a PDR DWT should be granted PDR.
Justification 7.69 To grant PDR to a DWT without the ability to properly evaluate the wind
resource at the site is counter intuitive and likely to lead to sub-optimal siting decisions and therefore increase impacts versus benefit.
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Decommissioning of Unused Equipment
7.70 Unused equipment installed under PDR that no longer functions for the purpose for which it was installed is likely to create an impact without a benefit.
Recommendation 7.71 Non-functional DWTs and ASHPs should be removed as soon as is practically
possible and the surrounding area returned to its original condition.
Justification 7.72 The decommissioning of unused equipment would minimise impact and
remove non functioning domestic microgenerators.
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8 CONCLUSIONS AND SUMMARY RECOMMENDATIONS
8.1 At this early stage there remains much to learn concerning the operational effects of both ASHP and DWTs, and therefore a pragmatic approach has been adopted which recommends a review in 3 years time once more experience is gained through careful installation.
8.2 Figure 8 and Figure 9 summarise the suggested PDR criteria.
Figure 8: Summary Decision Diagram for DWT Permitted Development
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Figure 9: Summary Decision Diagram for ASHP Permitted Development
8.3 DWT and ASHP PDR is complicated by the range of technologies and contexts
in which the technologies may be installed. The recommendations made seek to implement PDR with reference to the quantitative impact approach adopted for this research.
8.4 A balance has been sought between attempting to decrease all impacts to broadly acceptable evidence based levels whilst encouraging the uptake of sustainable microgeneration technology and an overall reduction in CO2 emissions.
8.5 A number of recommendations have been made with regard to additional requirements for product and installer certification schemes. These may be summarised as:
• standardised noise labelling of ASHPs to allow PDR siting criteria to be met
• requirements of best siting practice by certified DWT installers, including natural heritage best practice and the necessity to consult the CAA and Defence Estates on site and product suitability
• requirement on certified installers to retain a list or centralised database on installations so that future progress and impacts may be evidenced.
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9 BIBLIOGRAPHY Author Date Title/Source AWEA 2008
Small Wind Turbine Market Global Study, available at http://www.awea.org/smallwind/pdf/2008_AWEA_Small_Wind_Turbine_Global_Market_Study.pdf
BERR
2008 Microgeneration Installation Standard MIS 3003, available at http://www.greenbooklive.com/filelibrary/MIS_3003_Issue_1_2_Micro_wind_25-02-08.pdf
BERR 2008 Microgeneration Installation Standard MIS 3005, available at http://www.greenbooklive.com/filelibrary/MIS_3005_Issue_1_2_Heat_Pump_systems_25-02-08.pdf
BERR 2008 Factory Production Control Requirements, available at http://www.greenbooklive.com/filelibrary/MCS_010_-_Iss_1_2_Factory_Production_Control_requirements_250208.pdf
BERR 2008 Acceptance Criteria for Testing Required for Product Certification, available at http://www.greenbooklive.com/filelibrary/MCS_010_-_Iss_1_2_Factory_Production_Control_requirements_250208.pdf
BWEA 2007 Small Wind Turbine Performance and Safety Standard, available at http://www.bwea.com/pdf/small/BWEA%20Small%20standard.pdf
BWEA 2009 Small Wind Systems: UK Market Report 2009, available at http://www.bwea.com/pdf/small/BWEA%20SWS%20UK%20Market%20Report%202009.pdf
Communities and Local Government 2007 Planning for a Sustainable Future, available at http://www.communities.gov.uk/documents/planningandbuilding/pdf/planningsustainablefuture.pdf
Communities and Local Government 2007 Permitted Development Rights for Householder Microgeneration: Government Response to Consultation Replies, available at http://www.communities.gov.uk/documents/planningandbuilding/pdf/565952.pdf
Communities and Local Government 2007 Changes to Permitted Development: Consultation Paper 1 - Permitted Development Rights for Householder Microgeneration, available at http://www.communities.gov.uk/archived/publications/planningandbuilding/changespermitted
Communities and Local Government 2007 Domestic Installation of Microgeneration Equipment, Final report from a Review of the related Permitted Development Regulation, available at http://www.communities.gov.uk/publications/planningandbuilding/domesticinstallation
DECC Air Source Heat Pumps, available at http://www.lowcarbonbuildings.org.uk/micro/air/
DECC Ornithology: Birds and Renewable Energy
DECC 2008 Microgeneration Installation Standard MCS:007, available at http://www.microgenerationcertification.org/docs/standards/MCS%20007%20-%20Issue%201.5%20Product%20Certification%20Scheme%20Requirements%20-%20Heat%20Pumps%2025%20Feb%2009.pdf
DECC 2009 UK Renewable Energy Strategy, available at http://www.decc.gov.uk/en/content/cms/publications/lc_trans_plan/lc_trans_plan.aspx
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DECC 2009 Qualitative Issues in the Design of the GB Feed-in Tariffs” Report by Poyry and Element Energy, available at http://www.decc.gov.uk/en/content/cms/consultations/elec_financial/elec_financial.aspx
DTI 2006 Our Energy Challenge: Power from the People; Microgeneration Strategy, available at http://www.berr.gov.uk/files/file27575.pdf
Edmondson, D 2007 Microgeneration and Planning: Managing the Impacts of Microgeneration
Element Energy 2008 The Growth Potential for Microgeneration in England, Wales and Scotland, available at http://www.berr.gov.uk/files/file46003.pdf
Element Energy 2008 The Number of Microgeneration units installed in England, Wale, Scotland and Northern Ireland, available at http://www.berr.gov.uk/files/file49151.pdf
Energy Saving Trust Air Source Heat Pumps, available at http://www.energysavingtrust.org.uk/Generate-your-own-energy/Air-source-heat-pumps#
Energy Saving Trust 2004 Installing small wind-powered electricity generating systems, available at http://www.energysavingtrust.org.uk/Global-Data/Publications/Installing-small-wind-powered-electricity-generating-systems-CE72
Energy Saving Trust 2009 Location, Location, Location: Domestic Small-Scale Wind Field Trial Report, available at http://www.energysavingtrust.org.uk/Global-Data/Publications/Location-location-location-The-Energy-Saving-Trust-s-field-trial-report-on-domestic-wind-turbines
Ernst & Young 2007 Renewable Heat Support Mechanism, available at http://www.berr.gov.uk/files/file42043.pdf
European Commission 2006 Administrative and Planning Issues for Small Wind Turbines in Urban Areas, available at http://www.urbanwind.net/pdf/Reports_Planning_and_admin_issues_Europe_report.pdf
European Commission 2007 The Socio-Economic Issues Related to the Installation of Small Wind Turbines in the Built Environment, available at http://www.urbanwind.net/pdf/Reports_SocioEconomicCOMBINEDfinal.pdf
HVAC Guide to Good Practice – Heat Pumps, available at http://www.bsee.co.uk/news/fullstory.php/aid/4196/HVCA_launch_heat_pump_guide_.html
Möller, B 2006 How Wind Power Landscapes Change: An Attempt to Quantify Visual Impact on Land Use and Residents in Northern Jutland, Denmark
National Resource Canada 2009 Air Source Heat Pumps, available at http://oee.nrcan.gc.ca/publications/infosource/pub/home/heating-heat-pump/asheatpumps.cfm
NHBC Foundation 2008 Review of Microgeneration and Renewable Energy Technologies, available at http://www.nhbcfoundation.org/LinkClick.aspx?fileticket=UzYVWRQW%2fTY%3d&tabid=339&mid=774&language=en-GB
Rivière P. 2008 Existing seasonal performance indices for air-to-air heat pumps, available at http://www.heatpumpcentre.org/newsmail/HPC-news_1_2008.htm
RSPB Wind Farms, available at http://www.rspb.org.uk/ourwork/policy/windfarms/index.asp
Scottish Executive 2004 The feasibility of introducing in Scotland an absolute objectively measured permitted noise level which if breached during any time of the day would cause an offence liable to conviction, available at
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http://www.scotland.gov.uk/Resource/Doc/930/0010373.pdf
Scottish Executive 2007 Review of the General Permitted Development Order 1992 Final Report, available at http://www.scotland.gov.uk/Publications/2007/03/29102736/15
Scottish Executive 2007 Scottish Planning Policy: Renewable Energy, available at http://www.scotland.gov.uk/Resource/Doc/171491/0047957.pdf
Scottish Government 2007 Research on the General Permitted Development Order and Related Mechanisms - Research Findings, available at http://www.scotland.gov.uk/Publications/1998/07/4ecd4188-cb7b-4884-a986-636736e9b14f
Scottish Government 2008 Permitted Development Rights for Domestic Microgeneration Equipment: Consultation Paper, available at http://www.scotland.gov.uk/Publications/2008/03/04090052/10
Scottish Government 2009 The Town and Country Planning (General Permitted Development) (Domestic Microgeneration) (Scotland) Amendment Order 2009, available at http://www.uk-legislation.hmso.gov.uk/legislation/scotland/ssi2009/en/ssien_20090034_en.pdf
Scottish Government 2009 Permitted Development Rights for Domestic Microgeneration Equipment: Analysis of Consultation Responses, available at http://www.scotland.gov.uk/Publications/2009/02/06145853/0
The Carbon Trust 2009 Small-scale Wind Energy, Policy Insights and Practical Guidance, available at http://www.carbontrust.co.uk/publications/publicationdetail.htm?productid=CTC738
The Planning Service 2007 Microgeneration Permitted Development Rights: Consultation Document, available at http://www.planningni.gov.uk/index/news/news_consultation/news_consultations_archive/news-legislation-pd-rights.pdf
Source: SQW Energy
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10 APPENDICES APPENDIX 1 RESEARCH TOOLS STAKEHOLDER CONSULTATION QUESTIONS
The questions below follow on from the initial 2008 consultation Permitted Development Rights for Domestic Microgeneration Equipment. They expand on the proposals in line with the responses received and the ongoing consultations throughout the rest of the UK. A small number of questions are repeated to test the previous statements in light of technological advances, and to allow for additional stakeholders to comment on the identified issues.
Please note that unless table sectors are ‘greyed out’ answers may be given for both Micro Wind Turbines (MWT) and/or Air-Source Heat Pumps (ASHP).
Please tick YES or NO for each technology as appropriate, and/or fill in the COMMENTS section with any justification or relevant points you may wish to make. If you do not know the answer to a question or wish to omit it, we would be very grateful for text within the COMMENTS area declaring the same.
MWT ASHP QUESTION
YES NO YES NO
COMMENTS
GENERAL
Question 1: Do you agree with the principle of an impact approach64 for permitted development?
SCALE AND PERFORMANCE
Question 2: In striking a balance between impacts and carbon offsetting, do you think that a micro wind turbine (MWT) rotor diameter of up to 2.2 meters is reasonable for PD?
Question 3: Is it acceptable that PD would allow the highest part of a MWT to be up to 3 meters above the highest part of the roof structure?
Question 4: Under PD is it equitable to allow a swept rotor area of up to 3.8m2 for vertical axis wind turbines (VAWTs), the equivalent of a 2.2m diameter horizontal rotor?65
Question 5: Is it acceptable that free standing MWTs are subject to
64 An impact approach seeks to regulate developments by their assessed measurable impacts; usually in terms of scale and extent. 65 A VAWT limited by the 3m height above roof restriction would therefore have a diameter of around 1.25m.
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the same maximum diameter and swept area as those for building mounted MWTs, but with the limitation that no part should be higher than 11.1m and located at least 12 m from the boundary of the curtilage?
Question 6: Should a limit of one free-standing MWT per curtilage be set?
Question 7: Is the UK Microgeneration Certification Scheme 66 (MCS) recommendation that a wind assessment be carried out using an anemometer or estimated from adjusted NOABL67 data along with a disclaimer68 sufficient to guarantee performance?
NOISE AND VIBRATION
Question 8: With regard to noise do you agree that the UK Microgeneration Certification Scheme is sufficient to limit the output noise levels from operational air-source heat pumps69 and wind turbines70?
Question 9: Do you agree that the impact of noise should be dealt with by specific noise restrictions based on decibel levels at or within neighbouring dwellings71? Please state your thoughts on any levels and justify your answer with appropriate reasoning.
Question 10: With reference to any noise limits set for PD, is it appropriate that MCS Certified Installers would then be responsible for the noise assessment and appropriate installation of MCS approved MWT or ASHP devices? If not please identify any other means to achieve this.
Question 11: With regard to vibration and in line with the Microgeneration Certification Scheme, should PD rights set a
66 Documents can be viewed at: http://www.microgenerationcertification.org/ 67 Department of Trade and Industry / ETSU windspeed database. 68 “The performance of wind turbine systems is impossible to predict with any certainty due to the variability in the wind from location to location and from year to year. This estimate is based upon the best available information but is given as guidance only and should not be considered as a guarantee. For a greater level of certainty, it is recommended that on-site wind speed monitoring is undertaken for at least a year.” MCS 2009. http://www.microgenerationcertification.org/docs/standards/MIS%203003%20Issue%201.5%20Micro%20Wind%2025%20Feb%2009.pdf 69 BS EN14511:2004 70 http://www.bwea.com/pdf/small/BWEA_SWT_Standard_Feb2008.pdf 71 For example, based on the British Wind Energy Association Small Wind Turbine Performance and Safety Standard (29 February 2008) and WHO external night-time noise level guideline at dwellings of 45 dBLAeq. MWTs and ASHPs should not cause the internal noise level of habitable rooms to exceed 30dB LAEQ, 5min, and the external noise levels to exceed 45dB LAEQ, 5min at any neighbouring residential property.
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maximum allowable level of vibration (e.g. 0.5mm/s) within any habitable structure adjacent to the microgeneration? If answering please justify your response.
Question 12: With regard to structure-borne noise and vibration would it be appropriate to limit PD for MWTs or ASHPs to detached properties? Please justify your response.
NATURAL AND BUILT HERITAGE
Question 13: The majority of responses from the previous Scottish Government PD consultation indicated that there were no grounds to further constrain PD in areas designated for their landscape quality. Are certain landscape designations particularly sensitive to micro-wind development? Please comment and justify your answer evidentially.
Question 14: Do you agree that Local Planning Authorities should be able to restrict permitted development rights for micro-generation (for example, by use of Article 4 Directions) where the benefit from the technology is proven to be outweighed by its impact?
Question 15: In terms of natural heritage impacts and in light of a greater experience of MWTs is there any evidence of specific impacts on natural heritage? If answering, please provide evidence of impacts or otherwise.
Question 16: With regard to built heritage the majority of responses to the previous consultation believed that the setting of listed buildings would be adequately protected by not granting PD rights to microgeneration within their curtilage. Is there any new evidence to suggest otherwise?
Question 17: Do you agree with a restriction on stand-alone microgeneration development facing onto and visible from a highway in conservation areas?
Question 18: Do you agree with a restriction on stand-alone microgeneration development facing onto and visible from a highway in World Heritage Sites?
Question 19: For building mounted microgeneration is it appropriate that PD rights are not extended to Conservation Areas? Please justify your answer.
Question 20: For building mounted microgeneration is it appropriate that PD rights are not extended to World Heritage
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Sites? Please justify your answer.
Question 21: In line with the responses from the previous Scottish Government PD consultation, the colour of wind turbines or ASHPs should not be set, however MCS certified installers could follow set guidelines to minimise impacts. Is this appropriate?
SAFETY AND BUILDING STANDARDS
Question 22: In terms of safety and building standards does a limitation that MWTs and ASHPs must be installed by MCS certified installers in line with MCS guidelines provide sufficient protection?
ANY ADDITIONAL COMMENTS?
Figure A1: Online stakeholder PD questionnaire
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STAKEHOLDER CONSULTATION RESPONSE SUMMARY
Introduction
This working paper provides a summary of the stakeholder responses to the questionnaire on Permitted Development Issues: Domestic Wind Turbines and Air-Source Heat Pumps. Of the 31 written responses, 22 have been received from Government bodies, 3 from Environment and Community groups, and 6 from Businesses or Trade Organisations.
Summary of Responses
Question 1 Do you agree with the principle of an impact approach for permitted development?
Answered Yes No
Number of Responses 27 100% 0%
Specific comments
One respondent agreed with the principle of an impact approach for micro wind but disagreed on setting the same principle for air source heat pumps.
Question 2: In striking a balance between impacts and carbon offsetting, do you think that a Micro Wind Turbine (MWT) rotor diameter of up to 2.2 meters is reasonable for PD?
Answered Yes No
Number of Responses 20 50% 50%
Specific comments
Some of the responses raised concern about the lack of evidence to suggest that the proposed rotor diameter would produce less noise; others thought that placing constraints on the diameter may be unnecessarily restricting the performance, particularly as design and material technology advances.
However, even with those who were in agreement some respondents had additional suggestions: 1. The proposed measure should be subject to controls over proximity to neighbouring boundary. 2. That the recommended diameter is not restrictive so as to prejudice larger free standing MWTs. 3. The diameter of 2.2m is supported for building mounted MWT, but 3.0-3.5m would be more
reasonable for domestic free-standing units. Question 3: Is it acceptable that PD would allow the highest part of a MWT to be up to 3 meters above the highest part of the roof structure?
Answered Yes No
Number of Responses 19 42.1% 57.9%
Specific comments
Respondents in favour were in agreement with the Energy Saving Trust’s recommendation that for MWT to be effective, the highest part should be allowed to be at least 3 meters above the roof structure as turbines mounted below this level could be sub-optimally sited due to the effects of turbulence caused by the building structure and generation would be therefore be compromised.
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A few respondents thought that the proposed 3m was too excessive. They were of the opinion that the proposed measurement could result in the MWT units being highly visible with a likely adverse visual impact on neighbourhoods were numerous MWT units are installed.
Question 4: Under PD is it equitable to allow a swept rotor area of up to 3.8 square meters for vertical axis wind turbines (VAWTs), the equivalent of a 2.2m diameter horizontal rotor?
Answered Yes No
Number of Responses 16 43.8% 56.2%
Specific comments A few respondents felt that a swept rotor area of up to 3.8m2 are of such a scale that they would only look appropriate on the roof of a factory or multi storey block, and not in a domestic situation while others thought that the swept area limit on small wind turbines is unduly restrictive.
Question 5: Is it acceptable that free standing MWTS are subject to the same maximum diameter and swept area as those for building mounted MWTs, but with the limitation that no part should be higher than 11.1m and located at least 12m from the boundary of the cartilage?
Answered Yes No
Number of Responses 18 56% 44%
Specific comments
It was suggested that the best way to maximise output is through increased height which may have visual impacts. Enabling free standing turbines to sit above 10 metres would provide significant energy benefits. In addition, the impact on neighbours may be better mitigated through a distance measurement from the nearest neighbours’ boundary, rather than the boundary of the curtilage.
Concerns were raised that providing for “no part to be above 11.1 metres” is too restrictive and this would reduce the potential energy output. Also, the stated height limit is unnecessarily low and can undermine the effectiveness of a GPDO policy primarily aimed at easing the uptake of appropriately sited small scale renewable equipment.
Question 6: Should a limit of one free-standing MWT per curtilage be set?
Answered Yes No
Number of Responses 19 58% 42%
Specific comments
Amongst the respondents that agreed with this proposal, there were some differing opinions such as:
1. The stated distance should equal the GPDO total height limit, or “topple distance”.
2. The limit should be set except where the turbine will be used in an agricultural application (in a rural area free from obstructions e.g. trees buildings etc) and where there is no negative aesthetic impact visible from the nearest public highway.
Question 7: Is the UK Microgeneration Certification Scheme (MCS) recommendation that a wind assessment be carried out using an anemometer or estimated from adjusted NOABL data along with a disclaimer sufficient to guarantee performance?
Answered Yes No
Number of Responses 12 75% 25%
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Specific comments
Some respondents were of the opinion that the performance of MWT is not the role of the planning system. The emphasis should be on wind assessment as an indicator of a factor to be considered.
Concerns were raised about the reliability of the NOABL data especially in dense urban areas and that performance of a MWT cannot be absolutely guaranteed as stated in the disclaimer because it depends on various factors such as obstructions to wind flow.
Question 8a: With regard to noise do you agree that the UK Microgeneration Certification Scheme is sufficient to limit the output noise levels from operational air-source heat pumps?
Answered Yes No
Number of Responses 18 67% 33%
Specific comments
The current MCS scheme does not state noise levels for ASHPs.
The acceptability of a noise level should always depend on a site specific assessment and solution.
Question 8b: With regard to noise do you agree that the UK Microgeneration Certification Scheme (MCS) is sufficient to limit the output noise levels from operational wind turbines?
Answered Yes No
Number of Responses 14 71% 29%
Specific comments
One respondent suggested that there was not enough evidence to ascertain that the MCS is sufficient for assessing the noise impact of wind turbines.
Question 9: Do you agree that the impact of noise should be dealt with by specific noise restrictions based on decibel levels at or within neighbouring dwellings?
Answered Yes No
Number of Responses 22 82% 18%
Specific comments It was suggested that giving a clear noise level to manufacturers and using MCS to include noise compliance in the technology accreditation process is the most likely approach to ensure compliance and to ensure certainty.
The noise impact should be measured in decibels based on distance (or a set of distances) away from the product. These distance measures could be standardised for products and provided prior to purchase and installation so that an appropriate product choice can be made. A noise level of 45dB has been suggested.
Concerns were raised in relation to the limited experience of MWT and ASHPs with regard to advice on noise levels at or within neighbouring dwellings, and the proposal does not consider the cumulative effect of several units being installed in any one location.
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Question 10a: With reference to any noise limits set for PD, is it appropriate that MCS certified installers would then be responsible for the noise assessment and appropriate installations of MCS approved MWT devices?
Answered Yes No
Number of Responses 22 91% 9%
Question 10b: With reference to any noise limits set for PD, is it appropriate that MCS certfified installers would then be responsible for the noise assessment and appropriate installations of MCS approved ASHP devices?
Answered Yes No
Number of Responses 15 80% 20%
Specific comments (10a and 10b)
A main concern raised was the lack of adequate numbers of MCS approved installers for this proposal to be practical. Some respondents were in support of this proposal as it places responsibility on the installers to ensure that installations minimise noise impact.
Greater transparency and consistency from manufacturers is needed, which in turn will give end users and planning official’s information that can be comparable.
Set standards are required to ensure that all manufacturers’ publish their noise levels at the same levels.
Question 11: With regards to vibration and in line with the Microgeneration Certification Scheme, should PD rights set a maximum allowable level of vibration (e.g. 0.5mm/s) within any habitable structure adjacent to the microgeneration?
Answered Yes No
Number of Responses 17 59% 41%
Specific comments
Councils do not generally have adequate equipment to assess vibration within a building hence; there would be no way to check whether the microgeneration unit is PD, if a complaint was received.
It is important to establish rigorous maximum vibration levels to ensure continuing public support for renewables and to promote good design and installation.
Respondents questioned the scientific or legal basis for a vibration threshold of 0.5mm/s and suggested that this was based on a limited experience of vibration problems from operational MWT and ASHPs.
Question 12a: With regard to structure-borne noise and vibration would it be appropriate to limit PD for MWTs to detached properties?
Answered Yes No
Number of Responses 20 40% 60%
Question 12b: With regard to structure-borne noise and vibration would it be appropriate to limit PD for ASHPs to detached properties?
Answered Yes No
Number of Responses 14 36% 64%
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Specific comments (12b and 12b)
On the basis that the noise and vibration levels are set at the level prescribed by the MCS, the impact on non-detached properties should have been sufficiently considered therefore, provided satisfactory mitigation measures are used there should be no reason to limit PD for MWTs or ASHPs to the type of properties they can be fitted to.
It was also suggested that MWTs should be sufficiently isolated from the building fabric through some form of ‘damping’ mechanism.
In the case of ASHPs some felt that the units should be ground mounted only.
There were some concerns about the proposals, with some feeling that to introduce this would create a bias for homeowners thus limiting the opportunity for installation to those that do not reside in a detached property.
Question 13: The majority of response from the previous Scottish Government PD consultation indicated that there were no grounds to further constrain PD in areas designated for their landscape quality. Are certain landscape designations particularly sensitive to micro-wind development?
Answered Yes No
Number of Responses 12 56% 44%
Specific comments It was suggested that formal planning applications should still be required where the property falls within an AONB, Conservation Area, Listed Buildings, SSSI and/or any other sites of special importance to our national heritage.
Question 14: Do you agree that Local Planning Authorities should be able to restrict PD rights for micro-generation (for example, by use of Article 4 Directions) where the benefit from the technology is proven to be outweighed by its impact?
Answered Yes No
Number of Responses 16 63% 37%
Specific comments
It was felt that enabling Local Planning Authorities to restrict permitted developments may create uncertainty and the utility benefit to a consumer of micro-generation cannot be accurately predicted and/or appropriately weighed by a planning authority. The decision should not be made by a Local Planning Officer, who may not be suitably informed in these matters to make an objective decision.
Questions of how and by whom the benefit and impact are assessed were raised.
Question 15: In terms of natural heritage impacts and in light of a greater experience of MWTs is there any evidence of specific impacts on natural heritage?
Answered Yes No
Number of Responses 11 18% 82%
Specific comments A comment was made as to the lack of evidence to provide an informed answer to the question: “scientific evidence is currently scarce due to a lack of historical monitoring of these developments”.
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It was suggested that further research is needed on the impact of MWTs and the appearance, setting and character of heritage could be distorted by micro generation PD.
Question 16: With regard to built heritage the majority of responses to the previous consultation believed that the setting of listed buildings would be adequately protected by not granting PD rights to microgeneration within their curtilage. Is there any new evidence to suggest otherwise?
Answered Yes No
Number of Responses 14 0% 100%
Specific comments Permitted Development rights should not be granted within the curtilage of listed buildings. Development with respect to Listed buildings, Conservation Areas and World heritage sites need to be undertaken with the utmost sensitivity.
Question 17a: Do you agree with a restriction on stand-alone MWT microgeneration development facing onto and visible from a highway in conservation areas?
Answered Yes No
Number of Responses 19 68% 32%
Question 17b: Do you agree with a restriction on stand-alone ASHP microgeneration development facing onto and visible from a highway in conservation areas?
Answered Yes No
Number of Responses 14 71% 29%
Specific comments (17a and 17b)
Conservation areas should be offered sufficient protection against visual intrusion and PD rights should only extend to microgeneration units not facing onto and visible from highways. Such restrictions are necessary to ensure good precedence in such areas.
Question 18a: Do you agree with a restriction on stand-alone MWT microgeneration development facing onto and visible from a highway in World Heritage Sites?
Answered Yes No
Number of Responses 17 76% 24%
Question 18b: Do you agree with a restriction on stand-alone ASHP microgeneration development facing onto and visible from a highway in World Heritage Sites?
Answered Yes No
Number of Responses 12 83% 17%
Specific comments (18a and 18b) Those in favour of the restriction felt that it will enable control over any impact on the particular value of the site and any cumulative impacts and World Heritage Sites should be offered sufficient protection against visual intrusion
Question 19a: For building mounted MWT microgeneration is it appropriate that PD rights are not extended to Conservation areas?
Answered Yes No
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Answered Yes No
Number of Responses 18 67% 33%
Question 19b: For building mounted ASHP microgeneration is it appropriate that PD rights are not extended to Conservation areas?
Answered Yes No
Number of Responses 14 50% 50%
Specific comments (19a and 19b)
Conservation areas should be offered sufficient protection against visual intrusion and that PD rights may not be appropriate within conservation areas therefore planning permission can continue to be sought in these circumstances.
Some respondents thought that for Scotland to reach its potential in renewable energy generation it is important to minimise unnecessary restrictions and ASHPs are unlikely to have significant impact on the visual aspect of a conservation area.
Question 20a: For building mounted MWT microgeneration is it appropriate that PD rights are not extended to World Heritage Sites?
Answered Yes No
Number of Responses 18 83% 17%
Question 20b: For building mounted ASHP microgeneration is it appropriate that PD rights are not extended to World Heritage Sites?
Answered Yes No
Number of Responses 14 71% 29%
Specific comments (20a and 20b)
World Heritage Sites should be offered sufficient protection against visual intrusion, and PD rights may not be appropriate within such areas. Planning permission can continue to be sought in these circumstances.
World Heritage sites are far too sensitive and rare to allow any Permitted Development.
Question 21: In line with the responses from the previous Scottish Government PD consultation, the colour of wind turbines or ASHPs should not be set, however MCS certified installers could follow set guidelines to minimise impacts. Is this appropriate?
Answered Yes No
Number of Responses 19 74% 26%
Specific comments
This would be a matter for authorities to produce Supplementary Guidance appropriate to their area and it depends on the individual circumstances of the development proposal but there should be a minimum standard set nonetheless.
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Question 22: In terms of safety and building standards does a limitation that MWTs and ASHPs must be installed by MCS certified installers in line with MCS guidelines provide sufficient protection?
Answered Yes No
Number of Responses 15 100% 0%
Specific comments It was recommended that MCS will offer sufficient protection to those beyond the host property of any GPDO installed units.
Two of the respondents commented that there was a lack of sufficient evidence and/or information available to accurately respond.
General comments The Microgeneration Certification Scheme is an unhelpful website for Scottish users, as this is an English/Welsh Scheme, which refers to grants only available in England, or refers to the UK Planning Portal, which has no relevance to Scotland.
Changes to Permitted Development should facilitate the growth of these technologies in a way which minimises the potential impacts on other homeowners, without acting as a barrier to their growth.
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APPENDIX 2 STAKEHOLDER CONSULTEES The Edinburgh and Aberdeen workshops took place at Scottish Government facilities on the 31st August and 2nd September respectively. Each workshop followed the same structure (outlined in the above methodology) and the 5 break out groups were run in the same way. Both events were well attended and feedback was positive. Companies and Organisations Consulted
Aberdeen City Council- (Research & Grants Department) Aberdeen City Council- (Planning) Ampair Wind Turbines Angus Council- (Planning) Angus Council Argyle & Bute Council Archial Sustainable Futures Bat Conservation Trust Blue Planning & Development British Wind Energy Association Broughty Ferry Community Council Cairngorms National Park Authority Carbon Trust Changeworks City of Edinburgh Council Planning & Transportation City of Edinburgh Council Construction Licensing Executive Craiglockhart Community Council Dumfries & Galloway Council Dundee City Council Earth Energy / Ground Source Heat Pump Association East Ayrshire Council East Dunbartonshire Council East Lothian Council East Renfrewshire Council Ecoliving EDF Energy Edinburgh Napier University Eilean Siar Council Energy Renewed Energy Saving Trust Glasgow Council Go Greener Highlands & Islands Community Energy Council Highland Council Highlands & Islands Enterprise Institute of Historic Building Conservation Inverclyde Council (Noise) Larbert Stenhousemuir & Torwood Community Loch Lomond & Trossachs National Park Micropower Council
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Mid Lothian Council Mitsubishi Electric Moray Council (Noise) Moray Council Nick Forrest Associates Limited North Ayrshire Council (Noise) North Lanarkshire Council (Noise) Orkney Council (Noise) Proven Energy Renewable Devices Swift Turbines Renewables Connection Renfrewshire Council (Planning) RMP Acoustics Robert Gordon University Royal Environmental Health Institute of Scotland Royal Institution of Chartered Surveyors (RICS) Royal Society of the Protection of Birds (RSPB) Royal Town Planning Institute Scotland (RTPI) Salford University Scottish and Southern Energy Scottish Association of Building Standards Managers Scottish Borders Council Scottish Borders Council- environment Health Section Scottish Building Federation Scottish Construction Centre Scottish Enterprise Scottish Environment Protection Agency Scottish Federation of Housing Associations Scottish Natural Heritage (SNH) Scottish Renewables Scottish Sustainable energy federation Select SgurrEnergy Shetland Island Council (Planning) Socialist Environment and Resource Association (SERA) Solar and Wind Applications Solar Trade Association South Ayrshire Council (Planning) South Lanarkshire Council (Planning) Stirling Council (Planning) Strategic Development Planning Authority for Edinburgh and South East Scotland Sustainable Development Commission Taylor Wimpey Limited The Architectural Heritage Society of Scotland TUV-NEL Vokera Limited West Dunbartonshire Council (Planning) West Lothian Council (Planning) Windsave Limited World Wildlife Fund Scotland
ISSN 0950 2254ISBN 978 0 7559 7779 6(Web only publication)
www.scotland.gov.uk/socialresearch
The text pages of this document are produced from 100% ElementalChlorine-Free material.The paper carries the Nordic Ecolabel for low emissions duringproduction, and is 100% recyclable.
RR Donnelley B63168 12/09
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