What is Commissioning? - Mechanical & Electrical Design ...
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Transcript of What is Commissioning? - Mechanical & Electrical Design ...
What is Commissioning?
New building commissioning (Cx) is a means to
ensuring, through design reviews, functional testing,
system documentation, and operator training–that
systems and equipment in new buildings are
operating properly.
– BCA Best Practices
Commissioning
USS Ronald Regan Commissioning Ceremony
2-1/2 years to commission.
What is Commissioning?
Risk management technique
Helps insure owners get what they pay for
Provides early detection of problems through
design reviews and detailed testing
Enhances operator training and system
documentation
Energy and/or whole-building focus
Mechanical, electrical, lighting, plumbing, life
safety, building envelop
What is Commissioning?
1984 ASHRAE HVAC Commissioning Guideline Committee formed
1988 ASHRAE publishes HVAC Commissioning Guideline
1992 U.S. GSA develops HVAC Functional Inspection & Testing Guide
1993 U.S. Army Corps of Engineers develops Cx guide specification
1994 Executive Order 12902 requires a Cx program for federal agencies
1994 U.S. Army Corps of Engineers develops HVAC Commissioning
Procedures
1995 U.S. GSA publishes Building Commissioning Guide, Version 1
1996 ASHRAE publishes Guideline 1-1996: The HVAC Commissioning
Process
Terms Defined
New Building
Commissioning (Cx)
Existing Building
Retrocommissioning (RCx)
Recommissioning (RCx)
On-going commissioning (CCx/MBCx)
What is Existing Building Cx & Tune-Up?
Applying the commissioning process to improve the current
conditions/operations of an existing building
Typically focuses on:
• HVAC Systems
• HVAC Controls
• Lighting Controls
Evaluates building operation:
• What were the building systems originally designed to do?
• What are the building systems doing now?
• How can the building systems be optimized for current needs?
Benefits
Reduced operational cost and GHG emissions
Improved comfort
Mitigated indoor air quality problems
Increased operations staff knowledge
Increase occupant satisfactions/productivity
Increased property asset value
Utility incentives
Benefits – Survey ResultsNEMI Building Commissioning TAB Market Research Study (2005)
Industry Profile
Existing
$200M industry
660 Million SF
<1% building segment
Potential
$4B annual market
$30B energy savings potential (340 megatons CO2)
NEMI Building Commissioning TAB Market Research Study (2005)
Mills, 2009, Building Commissioning - Based on DOE/EIA (2003) energy
consumption, demand growth per the US EIA 2007 Annual Energy Outlook median
Cx energy savings of 16%.
Why Commission?
“The results demonstrate that commissioning is
arguably the single-most cost-effective strategy for
reducing energy, costs, and greenhouse-gas
emissions in buildings today.”
Building Commissioning: A Golden Opportunity for Reducing
Energy Costs and Greenhouse Gas Emissions” –
Lawrence Berkeley National Laboratory July 2009
Industry Profile
NEMI Building Commissioning TAB Market Research Study (2005)
Typical Costs and Benefits
332 EBCx + 77 NBCx projects = 643 buildings
Mills, E., et al, 2009, Building Commissioning
Commissioning Analysis
of 643 Buildings Cost
$/Sq. Ft.
Benefit
$/Sq. Ft.
Return on
Your
Investment
%
Simple
Payback
Period
Years
Whole
Building
Energy
Savings
Existing Building Cx 0.30$ 0.27$ 91% 1.1 16%
New Building Cx 1.16$ 0.28$ 23% 4.2 13%
Typical Costs and Benefits
Barriers to Market Expansion
Lack of owner awareness to need and value
Insufficient provider consistency of service
Varied and competing certification programs
Lack of mandates (i.e. codes, policy, etc.)
Low energy prices
Cost
The Tune-Up Process
Source: California
Commissioning
Collaborative
(BCA and NEBB list
similar processes)
Persistence
Summary of Deliverables by Phase
Source: California
Commissioning
Collaborative
PlanningGood Candidates for Tune-Ups
Unjustified high energy use
Frequent failure of energy systems
Excessive occupant comfort complaints
Buildings with energy management systems
Motivated owners / operators
Outdated building documentation, lack of
training on systems
Building staff knows problems, but lacks
time to fix
Opportunities
Investigation – Sources of Issues
Overrides due to other issues (warm-up time, poor comfort, etc.)
Hardware issues –actuator operation, controls linkage, sensor calibration
Improper control sequence, changes in space use
New Buildings Institute: 64% of economizers tested required adjustment
Top Opportunities – PCD Experience
1. Optimize equipment scheduling
2. Optimize outside airflow control (free-cooling & minimum ventilation)
3. Reset/reduce supply air static pressure
4. Reset air and water temperatures
5. Return VFDs to variable speed operation – Restoring Auto Control
6. Repair inoperable controls hardware (dampers & valves)
7. Optimize plant sequencing (including lockout control)
8. Calibrate sensors
9. Fix leaks
10. Clean heat transfer surfaces
Investigation
Review documentation and historical data
Interview personnel
Perform site observations
Data trending (DDC and/or portable loggers)
Point to point controls checkout & calibration (select points)
Functional performance tests (selective)
Test and balance measurements (selective)
Investigation – Trend Data
Potential Savings
Investigation – Inspection hall of fame
Restricted flow
Investigation – Inspection hall of fame
When freezing isn’t cold enough
Wash Me!
36.1°F
Investigation – Inspection hall of fame
When all else fails, put it in ‘hand’!!!
EO 13423 -Reduce use of ‘hand’ by 30% by 2015
Persistence – Strategies for Success
PO&M Plan
Equipment Lists
O&M and Systems Manuals
Points List and Sequence of Operation
System Diagrams
Equipment life and expected/documented efficiency
Maintenance schedule and task descriptions
Form for data tracking and collection
Training – plan and execute and periodic refreshers
Ongoing discussion with occupants and O&M personnel
Performance tracking
Persistence – Performance Tracking
Benchmark energy use (i.e. Energy Star or Utility Tracking
Software)
Performance and End-Use Monitoring
Trend key system parameters (chiller efficiency, system
pressure, run-time, etc)
Diagnostic and Reporting Software
y = 2.2041x - 89.443R² = 0.7974
-20
0
20
40
60
`80
100
120
140
160
180
200
0 50 100 150
Tons Delivered to Building
OSA Deg,F
Chiller Tons Delivered
tons
Linear (Series1)
Making Tune-Ups Cost Effective
Use in house resources to reduce costs
Gather building documentation
Perform focused PM tasks prior to launching RCx
Assist with trending / sequence testing
Install/Remove short term data logging equipment
Perform/Manage repairs/improvements
Track/trend measures following implementation
Selection Process
RFP or RFQ?
Define - Scope, systems, focus, goals, process
Qualifications, competence, previous
performance, and availability
Selecting a Tune-Up Provider
Third party or in-house objective provider
Direct, relevant experience
Communication / conflict resolution skills
Organization skills
Forensic personality
Independent viewpoint
Rapport
Availability
Retrocommissioning and LEED
EAp1 – Energy Efficiency BMPs
PM plan, Buidling Operation Plan, ASHRAE Level 1 Audit
EAp2 – Minimum Energy Performance
Energy Star > 69
EAc1 – Optimize Energy Performance
EAc2
Complete RCx process meeting LEED-EB guidelines
Investigation, Implementation, Ongoing Commissioning
EAc3 - Performance Measurement
Energy system end-use metering
Innovation in Operations – Unique O&M Strategy
Lessons Learned – Tune Ups
Communications and coordination with team is paramount.
Provider verifies to confirm operation.
Document, document, document.
Close coordination to track issues to resolution.
Provider raises level of facility performance and installing contractor performance.
O&M warranty documentation and training invaluable.
Case Study (RCx)
Optimize equipment scheduling
Duct static pressure reset
Supply air temperature reset
Optimize OA economizer
Hot water temperature reset
Optimize ventilation volume
Case Study (RCx)
Optimize ventilation volume
Optimize equipment scheduling
Temperature resets
CAV to VAV MZU conversion
Chiller replacement
Boiler retrofit
1M Square Feet (33 buildings)
U.S. Army
Fort Bragg, NC
Case Study (RCx)
Reduce VAV box min. settings
Turn off exhaust fans at night
Static pressure/Temperature resets
Optimize IDEC system
Fix data center air distribution
Obviate chiller spiking
$16,400 Implementation Cost
$23,000 Savings
133,000 Square Feet
Agilent Technologies
Loveland, CO
Case Study (RCx)
Optimize HVAC scheduling
Duct static pressure reset
Optimize IDEC operation
Clean condenser coils
Relocating MA sensor
Correct over-pressurization
Case Study (MBx)
Permanent Monitoring Systems
Identify ongoing savings – early detection
Continuous benchmarking
24 CA university campuses (UC, CSU systems)
46 buildings, 7M SF
10% ongoing energy savings
2.5 year payback on initial investment
$1 per SF costs
Getting Started
Get informed about RCx
Identify contractors/consultants
Identify facilities / benchmark
Determine what local utility and government incentives are available
Have a budget
Evaporative Cooling
Two-Stage Evaporative Cooling (Airside)
Head Start Learning Center (Commercial
Packaged)
Savings of up to 75% versus compressor-based
cooling
Application: Locations where average daily wet-
bulb range is fully below average daily drybulb
Range (i.e. Colorado, Utah, New Mexico…).
Two-Stage Evaporative Cooling (Water Side)
Useful for direct feeding high temperature cooling
applications
Increased efficiency for compressor-based cooling
systems
Peak demand savings.
Source: Wescor
Ground Source Heat Pumps
Ground Source Heat Pumps
Takes advantage of cool ground temperatures
Reduces peak demand by up to ~40% over existing /base efficient
systems
Consider hybrid with tower if:
space constrained site
to correct load imbalance
high drilling cost exists
Utilize a Ground Water “Economizer” function
DR friendly
Thermal Energy Storage
Thermal Energy Storage
Storage of cold water via ice or water based storage system
Demand savings: Replacing all or a portion of chiller operation during
peak demand periods with stored “cooling” from off-peak chilled water
production.
For winter peaking utilities, storage of heat.
Source: Poudre School DistrictSource: Steffes
Dedicated Outdoor Air System with Energy Recovery
Dedicated Outdoor Air System with Energy Recovery
DOAS = decoupled ventilation load = reduced fan sizing, reduced duct
losses/leaks (1/5 airflow of typical VAV system).
ERV = Saving of 75% on outdoor air load
Demand savings: From reduction in peak cooling power draw
Couples with radiant cooling or heating technologies, displacement
ventilation, distributed heat pump technology.
Source: Mumma
Couples with radiant cooling or
heating technologies, displacement
ventilation, distributed heat pump
technology.
DOAS Application: Large amounts of
variably occupied space - office
buildings, hospitals or schools.
ERV Application: Buildings in hot-
Variable Refrigerant Flow Systems
Application: Offices, schools, hotels, hospitals and other multi-room
buildings where personalize conditioning is desired. Historical
buildings where duct install is difficult or expensive.
Summer peak utilities can benefit - off-peak winter load that can
improve capital utilization and ROI. Decide to support based on local
rates, reserve margins, regulatory environment & other factors
Demand savings: Marginal, mostly part-load energy savings and
savings through ability to simultaneously heat/cool.
DR friendly
Displacement Ventilation
Application: Buildings with high ceilings, moderate peak cooling load
densities (<13 Btu/hr-ft2), large annual cooling energy consumption,
and require small quantities of fresh air with high air quality, such as
offices, public buildings.
Demand savings: Up to 20% on ASHRAE design ventilation
requirements.
Radiant Cooling / Chilled Beam
Application: Tight buildings with high sensible cooling loads, located
in low-humidity cooling climates.
Not buildings with appreciable latent loads (e.g., health/fitness clubs,
pools).
Demand Savings: Higher chilled water temperatures = increase cooling
efficiency. Also fan energy savings.
Active Chilled Beam- Source: Rumsey
Variable Refrigerant Flow Systems
Application: Offices, schools, hotels, hospitals and other multi-room
buildings where personalize conditioning is desired. Historical
buildings where duct install is difficult or expensive.
Summer peak utilities can benefit - off-peak winter load that can
improve capital utilization and ROI. Decide to support based on local
rates, reserve margins, regulatory environment & other factors
Demand savings: Marginal, mostly part-load energy savings and
savings through ability to simultaneously heat/cool.
DR friendly
Barriers To Adoption
May take 10-20 years to achieve any significant market penetration
after a technology is introduced into the market.1
Higher equipment costs compared to other, less efficient, technologies.
New technologies do not achieve market penetration unless SPB < 2
years. 1
Installation-specific design and difficulty evaluating the suitability of
individual installation sites.
Lack of knowledge base in design, operation, servicing and
maintenance and ownership costs (Education and Research).
Perception and natural resistance to change.
Performance uncertainties.
Manufacturer support and spare parts availability.
1Tiax, LLC – “Energy Consumption Characteristics of Commercial Buildings” (2002)
Mapleleaf Orthopedics
8,000 SF medical office, completed Dec 2007
Southern Colorado’s 1st
LEED Building –LEED 2.2 Gold
CRES award winnerwww.cres.org
Mapleleaf Orthopedics
30kW PV System meets 90%+ of energy
needs
Ground source heat
pumps (GSHP) 350%+ heating efficiency
23 EER cooling
Energy recovery
ventilator (ERV) reduces ventilation load by
75%
90% of spaces are daylit,
Dimming and occupancy
based lighting controls
ERV
GSHP
Lighting
Mapleleaf Orthopedics –Performance Metrics
Source: EIA CBECS 2003: Table C.12 Consumption and Gross Energy Intensity by Year Constructed for Sum of Major Fuels for Non-Mall Buildings, 2003
Period March 2008 - August 2008 Extrapolated
kWh Used/Year 51,360
kWh Produced/Year 47,854
Net kWh Used/Year 3,506
Energy Use Intensity (Btu/Square Foot/Year) 16.5
CBECS: Office US 1990-2003* 88.0
CBECS: West Mountain Region 1990-2003* 81.2
Mapleleaf Orthopedics Performs 80% Better Than a Typical Building
$/Year $ 5,187
$/SF/Yr $ 0.65
Resources
Building Commissioning Association
http://www.bcxa.org/
CA Commissioning Collaborative
http://www.cacx.org/
Green California
http://www.green.ca.gov/CommissioningGuidelines/default.htm
Database of State Incentives for Renewables/Efficiency
http://www.dsireusa.org
Procedural Standards for Retro-Commissioning of Existing Buildings
http://www.nebb.org
Net Zero Energy
Yet, how realistic is this vision?
How close do NZEBs come to realizing their design goals?
How much does it cost to design and build a net zero energy building?
Getting Started
Energy Independence and Security Act of 2007 (EISA 2007)
Goal of net zero energy for all new commercial buildings by 2030
Specifies a zero-energy target for 50% of U.S. commercial buildings by 2040
Net zero for all U.S. commercial buildings by 2050
ASHRAE Vision 2020 report (ASHRAE 2008) sets out
requirements for developing the tools by 2020
The AIA 2030 Challenge (AIA 2009) calls for
incrementally reducing energy use, starting with a 50%
reduction over existing buildings’ energy use and
increasing savings up to 2030
Getting There (Demand – Supply)
Build Tight…Ventilate Right
Daylighting
Insulation 10/20/40/60
Passive solar heating / control gain
High-efficiency HVAC equipment
Energy reuse
Natural ventilation / ‘Free’ cooling
Evaporative cooling
Ground-source heat pumps
Ocean water cooling
ZEB Database
9 projects
<20,000 SF
1 or 2 story commercial
http://zeb.buildinggreen.com/
High performance buildings database
Movement Climbing Gym
Carbon Neutral
Daylighting
Air source heat pumps
Evaporative cooling
Solar Thermal
Solar PV
DHA
LEED-H Platinum
Building 50%+ better than code
LPD 25% better than code, advanced lighting controls
PV handles 22% of electric usage
GSHP, Heat Recovery
Hyland Village Community
Get informed about RCx
Identify contractors/consultants
Identify facilities / benchmark
Determine what local utility and government incentives are available
Have a budget
Defining Net Zero Energy
Zero net site energy useIn this type of ZNE, the amount of energy provided by on-site renewable energy sources is equal to the amount of energy used by the building. In the United States, “zero net energy building” generally refers to this type of building.Zero net source energy useThis ZNE generates the same amount of energy as is used, including the energy used to transport the energy to the building. This type accounts for losses during electricity transmission. These ZNEs must generate more electricity than zero net site energy buildings.Net zero energy emissionsOutside the United States and Canada, a ZEB is generally
