Variable Capacity Heat Pump RTF Sub-Committee October 26 , 2011

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


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


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


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



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%


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



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


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



PNW Medium Office VC HPEnergy Use per SF

VRF Heat Pump

Cooling


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


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



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%


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


3

51.3%$28193.1835Spokane

Small Office ASHRAE System #3 (Packaged single zone AC with gas heat)

2

62.5%$31983.1835Seattle


1

% HVAC Savings

BPA Incentive

($)

SPB (years)

BCRIncr. Cost ($ / ton)

Location (TMY)

Baseline SystemVRF HP

Measure #

60%$343


60.7%$41273.6860Spokane


4

65.3%$36073.1860Seattle


3

51.3%$28193.1835Spokane


2

62.5%$31983.1835Seattle


1

% HVAC Savings

BPA Incentive

($)

SPB (years)


Location (TMY)


Measure #


Medium Office VRF Savings Summary

33%$240


42.5%$37865.5540Spokane

Medium Office ASHRAE System #6 (Packaged VAV with electric reheat)

8

31.5%$34854.8540Seattle


7

25.0%$9932.6540Spokane

Medium Office ASHRAE System #5 (Packaged VAV with gas boiler reheat)

6

34.9%$13533.4540Seattle


5

% HVAC Savings

BPA Incentive

($)

SPB (years)


Location (TMY)


Measure #

33%$240


42.5%$37865.5540Spokane


8

31.5%$34854.8540Seattle


7

25.0%$9932.6540Spokane


6

34.9%$13533.4540Seattle


5

% HVAC Savings

BPA Incentive

($)

SPB (years)


Location (TMY)


Measure #


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%


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.


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.


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?


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?


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?

Variable Capacity Heat Pump RTF Sub-Committee October 26 , 2011

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Transcript of Variable Capacity Heat Pump RTF Sub-Committee October 26 , 2011