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Heat Pump Replacement Savings <br />Assumptions <br />Rooms served by heat pumps are open from 6:00 to 4:00, M - F (50 hours per week), 50 weeks per year. <br />Assume that heating is required whenever the OAT is less than 60 degrees F. Assume further that the load factor increases <br />from "0" at that temperature to 100% as the temperature decreases to the lowest bin temperature. <br />Assume that cooling is required whenever the OAT is greater than 70 degrees F. Assume further that the load factor <br />increases from "0" at that temperature to 100% as the temperature increases to the highest bin temperature. <br />A. General Data for Baseline and Post Operation <br />Electric energy rate (ECR) $0,075 /kW-hr Based on Honeywell utility bill analysis <br />Electric demand rate (EDR) $12.00 MW Based on Honeywell utility bill analysis <br />B. Baseline Operation <br />Heating system capacity (HSC) 3,639,000 BTU/hr Based on 4 50 MBH heating sections <br />Average heating system COP (HCOP) 3.9 Typical average value for older heat pumps; verify during IGA <br />The heating system load is given by HSLF x HSC x Bin Hours/1000000, where HSLF is given by 1.33 - 0.022 x Bin Temp. <br />Average Bin <br />Temp, deg F <br />(From <br />"Weather <br />Data") <br />Bin Hours <br />(From <br />"Weather <br />Data") <br />Heating <br />System <br />Load <br />Factor <br />(HSLF) <br />Heating <br />System <br />Output, <br />Btu/hr <br />Heating <br />System <br />Load, <br />MMBTU <br />5T5 <br />642 <br />4% <br />135,189 <br />86.79 <br />52.5 <br />656 <br />11% <br />402,655 <br />264,14 <br />47.5 <br />609 <br />18% <br />670,122 <br />408A0 <br />415 <br />488 <br />26% <br />937,588 <br />457.54 <br />37.5 <br />697 <br />33% <br />1,205,055 <br />839.92 <br />32.5 <br />754 <br />40% <br />1,472,521 <br />HUM <br />27,5 <br />532 <br />48% <br />1,739,988 <br />925.67 <br />22J <br />256 <br />55% <br />2,007,454 <br />513.91 <br />17.5 <br />248 <br />63% <br />2,274,921 <br />564.18 <br />12.5 <br />118 <br />70% <br />2,542,387 <br />300.00 <br />7.5 <br />90 <br />77% <br />2,809,854 <br />252.89 <br />2.5 <br />70 <br />85% <br />3,077,320 <br />215.41 <br />-2.5 <br />13 <br />92% <br />3,344,787. <br />43.48 <br />-7.5 <br />6 <br />99% <br />3,612,253 <br />1 21.67 <br />Annual heating system load (AHSL) <br />6,004.00 MMBTL Sum of bin heating system loads in above table <br />Annual electrical energy used for heating (AHE) <br />451,198 kW-hrs <br />mm AHSL x I OOOOOO/HCOP/3412 <br />Number of heating months (HM) <br />5.5 <br />= sum of heating bin hours/(8760 x 44/52 x 517 » 50/168) x 12 <br />Average heating system load factor (AHSLF) <br />32% <br />weighted average load factor from above table <br />Ave monthly htg system power draw (AMHSPD) <br />87.1 kW <br />= AHSLF x HSCIHCOP/3412 <br />Annual heating system demand (AHSD) <br />479 kW <br />= AMHSPD x HM <br />Cooling system capacity (CSC) <br />145 tons <br />Cooling system efficiency (CSE) <br />1.50 kW/ton <br />Typical value for older heat pumps <br />The cooling system load is given by CSLF x CSC x Bin Hours, where CSLF is given by -2.8 + 0.04 x OAT <br />3.24 <br />