DELIVERING HIGH PERFORMANCE HVAC SYSTEMS IN …

DELIVERING HIGH

PERFORMANCE HVAC

SYSTEMS IN COMMERCIAL

BUILDINGS

►October 21, 2020

www.ma-eeac.org Consultant Presentation on C&I HVAC

AGENDA

►Commercial HVAC System Functional Purpose

►Challenges to reaching said goals

►Solutions to consider

►Next Steps

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COMMERCIAL HVAC PRIORITIES

►Space conditioning – provide a comfortable space to work, learn, live, and do business

►Indoor air quality – provide a safe, clean, and healthy indoor environment for occupants

►Cost Competitive – achieve the two above goals at reasonable cost (including environmental costs!)

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COMMERCIAL HVAC PRIORITIES –

PROVIDE SPACE HEATING►The dominant use of energy in commercial buildings

is space heating; more so in New England

►Cooling is a smaller % of energy use, but most C&I customers have some form of cooling

►Humidity controls also an important factor| 4



PROVIDE SPACE COOLING►Cooling is a smaller % of energy use, but most C&I

customers have some form of cooling

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Source: http://ma-eeac.org/wordpress/wp-content/uploads/MA-CI-Market-Characterization-Study.pdf

► “The large majority of Massachusetts

businesses use standalone non-

central cooling equipment”

► “PTACs and window/wall cooling

units are common across all size of

businesses but are concentrated in

lodging, hospitals, and campuses

where they likely provide cooling for

small spaces within larger

buildings.”

http://ma-eeac.org/wordpress/wp-content/uploads/MA-CI-Market-Characterization-Study.pdf


COMMERCIAL HVAC PRIORITIES – PROVIDE

HEALTHY INDOOR AIR QUALITY

►Provide fresh outdoor air− Code Requirement = ASHRAE 62.1

− Prescribed volume of fresh outdoor air and allowable level of CO2 based on occupancy, size and use of space

►Exhaust undesirable air

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Mechanical Ventilation “Natural” Ventilation



PROVIDE HEALTHY INDOOR AIR QUALITY

►Filter air for particulates− Minimum Efficiency Reporting Values (MERV) measures a

filter's ability to capture particles

− Filters both recirculated indoor air and incoming outdoor air

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MERV Rating Average Particle Size Efficiency in Microns

1-4 3.0 - 10.0 less than 20%

6 3.0 - 10.0 49.9%

8 3.0 - 10.0 84.9%

101.0 - 3.0 50% - 64.9%, 3.0 - 10.0 85% or

greater

121.0 - 3.0 80% - 89.9%, 3.0 - 10.0 90% or

greater

140.3 - 1.0 75% - 84%, 1.0 - 3.0 90% or

greater

16 0.3 - 1.0 75% or greater

Higher rating

= finer filter

Finer filters

increase

pressure drop

and use more

fan power

Source: https://www.epa.gov/indoor-air-quality-iaq/what-merv-rating-1

https://www.epa.gov/indoor-air-quality-iaq/what-merv-rating-1



COST COMPETITIVE (INTERNAL)

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►Long-lasting assets require more thorough analysis− Lifecycle costs more important than first cost/installed cost

− Even with landlord/tenant split – somebody is on the hook to pay for lifecycle cost of HVAC system eventually

How

decisions

are often

madeBetter way

to make

decisions

Source: https://cdn.facilityexecutive.com/wp-content/uploads/2020/01/Xylem-HVAC-life-cycle-study.pdf

https://cdn.facilityexecutive.com/wp-content/uploads/2020/01/Xylem-HVAC-life-cycle-study.pdf


COMMERCIAL HVAC PRIORITIES PURPOSE –

COST COMPETITIVE (EXTERNAL)

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►Environmental degradation is a cost− BU Center for Computing & Data Sciences will “become the

largest fossil fuel free building in the Boston area”

− Market leaders like BU – case study for HVAC design that incorporates external/societal cost of carbon

Source: https://www.bu.edu/sustainability/what-were-doing/green-buildings/center-for-computing-data-sciences/

https://www.bu.edu/sustainability/what-were-doing/green-buildings/center-for-computing-data-sciences/


CHALLENGES FOR COMMERCIAL

HVAC

►Existing/legacy infrastructure

►Building envelope

►Operations & Controls

►Customer Economics & Climate Goals

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CHALLENGES FOR COMMERCIAL HVAC

– EXISTING/LEGACY INFRASTRUCTURE

►Legacy equipment and existing infrastructure make modernizing HVAC systems difficult− Like-for-like replacements are common

− Often need to overhaul central plant and distribution system

► Note: old systems usually unable to consistently meet modern code

minimum outdoor air requirements (ASHRAE 62.1)

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HVAC – BUILDING ENVELOPE►Leaky windows and walls mean much of the energy

consumed to condition a building is wasted

► Note: many buildings rely on leakiness to meet minimum ventilation

► Not ideal or efficient| 12



HVAC – OPERATIONS & CONTROLS

►Controls vary by building− Large buildings often have legacy pneumatic (pressure-

based) controls or some combo of legacy and new controls

− Smaller buildings may only have unitary controls or T-stats

− Modern controls create more data; useful for trend analysis but can potentially overwhelm building operators

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HVAC – CUSTOMER ECONOMICS►Price of gas doesn’t include carbon costs

►Price of electricity includes some emissions reduction costs (RPS/CES, RGGI, etc.)

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what customers pay

+ what society pays

Source: https://www.eia.gov/outlooks/aeo/

https://www.eia.gov/outlooks/aeo/



HVAC – CUSTOMER ECONOMICS►Cheap gas/expensive electricity impacts customer

economics− Puts all-electric systems at a competitive disadvantage

− Makes envelope and heating system upgrades less cost effective

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what customers pay

+ what society pays

+ what society pays using EPA social cost of carbon

Source: https://www.eia.gov/outlooks/aeo/

https://www.eia.gov/outlooks/aeo/


SOLUTIONS FOR COMMERCIAL

HVAC

►Controls upgrades and/or retro-commissioning

►Weatherization

►Vendor and Customer training

►Finance Solutions

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HVAC – CONTROLS UPGRADES

►Upgrading old pneumatics to direct digital control (DDC) allows for modern sequence of operations

►ASHRAE Guideline 36 sets standards for High-Performance Sequences of Operation for HVAC Systems− Meeting space conditioning and indoor air

quality performance at highest energy efficiency

− Allows for real-time fault detection and diagnostics.

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SOLUTIONS FOR COMMERCIAL HVAC

– RETRO COMMISSIONING (RCX)

►Retro-commissioning (“RCx”)− Testing, verification, and upgrade protocol an existing

building controls to identify and correct operational issues

− Should comprehensively optimize system to deliver space conduiting and indoor air quality for least energy input

►Program Administrators call it Equipment & System Performance Optimization (“ESPO”) w/ 3 paths− Low/No cost tuning measures (prescriptive)

− Whole Building/Process (custom)

− Monitoring-based (custom)

►Regional collaboration on developing common set of tools, approaches and savings methodologies− Example: California Commissioning Collaborative

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HVAC – WEATHERIZATION

►Insulation/air sealing can help reduce the size of heating/cooling equipment.

►Can be comprehensive… can also be simple!

►Recently Implemented Copley Library Measures− Sealing windows, doors and cracks in the building envelope

− Replacing windows with high efficiency glass.

− Cap abandoned exhaust openings and vent shafts | 19


SOLUTIONS FOR COMMERCIAL HVAC

– VENDOR AND CUSTOMER TRAINING

“If a building’s systems are

improperly installed,

commissioned, or

maintained, the building will

not function as intended, not

only hindering its energy and

indoor environmental

performance but also

dissuading customers from

future investments in energy-

efficient technologies,

thereby slowing their

adoption.”

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HVAC – FINANCE SOLUTIONS

►Financing for customers motivated by first cost− Small business customers

− Customers w/ tenant/landlord split incentives

− Developers who build and flip buildings

►Help facility managers make the business case for HVAC upgrades to their own financial decision makers

►Educating and instilling confidence in financial decision-makers’ that savings are real− Hard to prove a counter-factual

− Guaranteed savings from structures like Energy Savings Performance Contracts helpful for institutional customers

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OPPORTUNITIES TO BRING IT ALL

TOGETHER – RETROFITS

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►Add controls to heat pumps previously installed for cooling− During prior plan cycles PAs were not allowed to claim

displaced fossil fuel savings

− Adding controls to optimize heat pumps and primary heating system could provide incremental fossil fuel savings

− Major system components have already been paid for

− Train contractors on how to do this going forward!



TOGETHER – NEW CONSTRUCTION

►Variable Refrigerant Flow (VRF) Heat-Pumps− Rather than distributing heating or cooling through vents

(air-based system) or steam/hot water (hydronic system) VRF systems circulate refringent

− Refrigerant is a highly energy efficient distribution medium

− Allows for simultaneous heating and cooling, and transfer of heat from one space to another when sunlight/shade creates uneven temperatures within a building

►Dedicated outdoor air system (DOAS) and Energy recovery ventilation (ERV)− Rather than conditioning a mix of fresh air and recirculated

indoor air, a DOAS brings in 100% outdoor air

− Heat recovery recaptures much of the embedded energy in exhaust air

− Potential to claim non-energy benefits associated w/ improved air quality!

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TOGETHER – NEW CONSTRUCTION

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Source: https://betterbricks.com/uploads/resources/VHE-DOAS_SummaryReport.pdf

heating/coolingventilation

https://betterbricks.com/uploads/resources/VHE-DOAS_SummaryReport.pdf



TOGETHER – END OF LIFE REPLACEMENT

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Source: https://be-exchange.org/wp-content/uploads/2019/06/HPRT_techprimer_DOAS_.pdf

!

►NYC Retrofit Accelerator: VRF + DOAS w/ HRV

►Not a silver bullet, but this is where the market is heading

https://be-exchange.org/wp-content/uploads/2019/06/HPRT_techprimer_DOAS_.pdf


SUMMARY

►Commercial HVAC systems serve the purpose of delivering space conditioning and indoor air quality cost-effectively

►Legacy systems/infrastructure and low natural gas costs are a head-wind to meeting energy/climate goals

►Training on use and optimization of complex systems are essential

►Program Administrators should lead the HVAC market to new technologies/solutions as they did for lighting

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