Slide 1
B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Variable Capacity Heat Pump RTF Sub-CommitteeOctober 26, 2011
Mira Vowles, P.E., CEM Emerging Technology Project ManagerBPA Energy Efficiency
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
PNW Small Office BaselineEnergy Use per SFRTU Gas Furnace Energy Use per Square Foot
Cooling
(kWh/SF)Heating (Th/SF) Fans (kWh/SF) Total HVAC (kWh/SF)
Seattle 0.7 0.0 6.4 7.2
Spokane 1.2 0.1 6.5 7.7
RTU Heat Pump Energy Use per Square Foot
Cooling (kWh) Heating (kWh) Fans (kWh) Total (kWh)
Seattle 0.7 0.6 6.4 7.7
Spokane 1.2 1.8 6.5 9.5
Based on EnergyPro model for PNW locations
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
PNW Small Office VC HPEnergy Use per SF
VRF Heat Pump Energy Use per Square Foot
Cooling
(kWh/SF)Heating (kWh/SF)
Fans (kWh / SF) Total HVAC (kWh/SF)
Seattle 1.2 0.7 0.7 2.7
Spokane 1.3 1.6 0.8 3.7
VRF Heat Recovery Energy Use per Square Foot
Cooling
(kWh/SF)Heating (kWh/SF)
Fans (kWh/SF)
Branch Box (kWh / SF)
Total HVAC (kWh/SF)
Seattle 1.3 0.8 0.7 0.0 2.8
Spokane 1.4 1.7 0.8 0.0 4.0
Based on EnergyPro model for PNW locations
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Small Office VRF Savings Summary
Measure Description Location (TMY)Electric Savings
(kWh / SF)Gas Heat Offset
(Therms / SF)% HVAC Electric
Savings
Single zone RTU with gas heat replaced on burn-out to VRF HP system
Seattle 4.5 0.0 25%
Single zone RTU with gas heat replaced on burn-out to VRF HP system
Spokane 3.9 0.1 21%
Single zone RTU heat pump replaced on burn-out to VRF HP system
Seattle 5.0 28%
Single zone RTU heat pump replaced on burn-out to VRF HP system
Spokane 5.8 30%
Average 4.8 (kWh / SF) 26%
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
PNW Medium Office Energy UseVRF Heat Pump
Cooling (kWh) Heating (kWh) Fans (kWh) Total (kWh)
Seattle 52,759 17,252 22,320 92,331
Spokane 55,515 34,124 24,510 114,149
VRF Heat RecoveryCooling (kWh) Heating (kWh) Fans (kWh) Branch Box (kWh) Total (kWh)
Seattle 53,069 9,439 22,320 1,956 86,784
Spokane 52,075 29,633 24,510 1,917 108,135
VAV Gas Boiler ReheatCooling (kWh) Heating (therms) Fans (kWh) Pumps (kWh) Total (kWh)
Seattle 87,880 3,400 53,437 618 141,935
Spokane 89,446 4,938 61,871 902 152,219
VAV Electric ReheatCooling (kWh) Heating (kWh) Fans (kWh) Total (kWh)
Seattle 85,708 58,628 52,853 197,189
Spokane 86,970 84,725 60,665 232,360
Based on EnergyPro model for PNW locations
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
PNW Medium Office BaselineEnergy Use per SF
VAV Gas Boiler Reheat
Cooling
(kWh/SF)Heating (Th/SF)
Fans (kWh/SF)
Pumps (kWh/SF)
Total HVAC (kWh/SF)
Seattle 2.1 0.1 1.3 0.0 3.4
Spokane 2.2 0.1 1.5 0.0 3.7
VAV Electric Reheat
Cooling
(kWh/SF)Heating (kWh/SF)
Fans (kWh/SF)
Total HVAC (kWh/SF)
Seattle 2.1 1.4 1.3 4.8
Spokane 2.1 2.0 1.5 5.6
Based on EnergyPro model for PNW locations
Slide 7
B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
PNW Medium Office VC HPEnergy Use per SF
VRF Heat Pump
Cooling
(kWh/SF)Heating (kWh/SF)
Fans (kWh / SF)
Total HVAC (kWh/SF)
Seattle 1.3 0.4 0.5 2.2
Spokane 1.3 0.8 0.6 2.8
VRF Heat Recovery
Cooling
(kWh/SF)Heating (kWh/SF)
Fans (kWh/SF)
Branch Box
(kWh / SF)Total HVAC (kWh/SF)
Seattle 1.3 0.2 0.5 0.0 2.1
Spokane 1.3 0.7 0.6 0.0 2.6
Based on EnergyPro model for PNW locations
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Medium Office VRF Savings Summary
Measure Description Location (TMY)Electric Savings
(kWh / SF)Gas Heat Offset
(Therms / SF)% HVAC Electric
Savings
Packaged VAV with gas boiler replaced on burn-out to VRF HP system
Seattle 1.2 0.1 35%
Packaged VAV with gas boiler replaced on burn-out to VRF HP system
Spokane 0.9 0.1 25%
Packaged VAV with elec reheat replaced on burn-out to VRF HP system
Seattle 2.5 53%
Packaged VAV with elec reheat replaced on burn-out to VRF HP system
Spokane 2.8 51%
Average 1.9 (kWh / SF) 41%
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Small Office VRF Cost Effectiveness
60%$343
per ton3.2BCRAverage
60.7%$41273.6860Spokane
Small Office ASHRAE System #4 (Packaged single zone heat pump)
4
65.3%$36073.1860Seattle
Small Office ASHRAE System #4 (Packaged single zone heat pump)
3
51.3%$28193.1835Spokane
Small Office ASHRAE System #3 (Packaged single zone AC with gas heat)
2
62.5%$31983.1835Seattle
Small Office ASHRAE System #3 (Packaged single zone AC with gas heat)
1
% HVAC Savings
BPA Incentive
($)
SPB (years)
BCRIncr. Cost ($ / ton)
Location (TMY)
Baseline SystemVRF HP
Measure #
60%$343
per ton3.2BCRAverage
60.7%$41273.6860Spokane
Small Office ASHRAE System #4 (Packaged single zone heat pump)
4
65.3%$36073.1860Seattle
Small Office ASHRAE System #4 (Packaged single zone heat pump)
3
51.3%$28193.1835Spokane
Small Office ASHRAE System #3 (Packaged single zone AC with gas heat)
2
62.5%$31983.1835Seattle
Small Office ASHRAE System #3 (Packaged single zone AC with gas heat)
1
% HVAC Savings
BPA Incentive
($)
SPB (years)
BCRIncr. Cost ($ / ton)
Location (TMY)
Baseline SystemVRF HP
Measure #
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Medium Office VRF Savings Summary
33%$240
per ton4.1BCRAverage
42.5%$37865.5540Spokane
Medium Office ASHRAE System #6 (Packaged VAV with electric reheat)
8
31.5%$34854.8540Seattle
Medium Office ASHRAE System #6 (Packaged VAV with electric reheat)
7
25.0%$9932.6540Spokane
Medium Office ASHRAE System #5 (Packaged VAV with gas boiler reheat)
6
34.9%$13533.4540Seattle
Medium Office ASHRAE System #5 (Packaged VAV with gas boiler reheat)
5
% HVAC Savings
BPA Incentive
($)
SPB (years)
BCRIncr. Cost ($ / ton)
Location (TMY)
Baseline SystemVRF HP
Measure #
33%$240
per ton4.1BCRAverage
42.5%$37865.5540Spokane
Medium Office ASHRAE System #6 (Packaged VAV with electric reheat)
8
31.5%$34854.8540Seattle
Medium Office ASHRAE System #6 (Packaged VAV with electric reheat)
7
25.0%$9932.6540Spokane
Medium Office ASHRAE System #5 (Packaged VAV with gas boiler reheat)
6
34.9%$13533.4540Seattle
Medium Office ASHRAE System #5 (Packaged VAV with gas boiler reheat)
5
% HVAC Savings
BPA Incentive
($)
SPB (years)
BCRIncr. Cost ($ / ton)
Location (TMY)
Baseline SystemVRF HP
Measure #
Slide 11
B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Proposed VRF Measures
VC HP Measure #
Measure Description
Average Electric
Savings (kWh / ton)
Total Building % Electric Savings
1Office Building VRF HP
system retrofit (< 80 tons per building)
1,573 26%
2Office Building VRF HP system retrofit (>= 80
tons per building)1,119 41%
Slide 12
B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Variable Refrigerant Flow System Definition
Variable refrigerant flow (VRF) systems, either heat-pump or heat-recovery styles, provide heating and air-conditioning, and typically consist of:
1. An outdoor unit with inverter driven compressor(s) and condenser fan, over 6 tons of capacity (72,000 Btu/h),
2. Multiple indoor units with multi-speed fans, electronic expansion devices and dedicated microprocessors,
3. Refrigerant piping between the outdoor and indoor units,
4. A zone temperature control device interlocked with a system controller.
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Office Building Definition A building used primarily for office functions, including
desk-work, reading and light equipment (computer, copier, printer, telephone, etc.) use.
Office occupancies are further defined by
overall occupant densities between 50 and 300 square feet per person,
overall lighting power densities between 0.5 and 2 watts per square foot, and
overall equipment plug loads between 0.1 and 1.5 watts per square foot.
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
Office Building Definition
Can whole building regression analysis be used to verify savings?
How many systems need to be evaluated?
How can buildings with significant other changes be excluded?
Other?
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
VRF Program Evaluation Questions
Can whole building regression analysis be used to verify savings?
How many systems need to be evaluated?
How can buildings with significant other changes be excluded?
Other?
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B O N N E V I L L E P O W E R A D M I N I S T R A T I O N
VRF Program Delivery Questions Can this be a utility equipment rebate program, instead of
an upstream program?
Limit to replacement on burn-out?
How to ensure replacement on burn-out?
Limit to baseline systems?
How to ensure baseline systems?
Other?