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<br /> <br />EXHIBIT D <br />FACILITY OPERATING PARAMETERS & <br />UTILITY SAVINGS CALCULATION METHODS <br />Public Works <br /> <br />VFD - Control with VAV Boxes <br /> <br /> <br />Energy Calculations - Variable Frequency Drives Optimization <br />BASELINE PROPOSED SAVINGS <br />HVACHRS <br /> <br />Proposed Proposed Proposed Ventilation Fan Energy Ventilation Fan Energy Ventilation <br />SUPPLY O.A. Measured Baseline Affected Proposed Baseline Fan Energy Cooling Cooling Cooling <br /> <br />S.F. CFM O.A. CFM % Flow <br />AHU # AREA SERVED CFM CFM KW Hrs/Wk Hrs/Wk Hrs/Wk % Flow KWH Therms KWH KWH Therms KWH KWH Therms KWH <br /> <br />AHU-1 Offices 10,150 2350 8.95 86.50 87 50 60% 7,862 2,350 60% 5,018 532 9,696 2,900 308 5,605 2,117 225 4,092 <br /> <br />TOTAL 5,018 532 9,696 2,900 308 5,605 2,117 225 4,092 <br /> <br /> <br /> <br />Assumptions <br /> <br />VARIABLES CALCULATIONS <br />See Table Above ...PRESENT HRS/WK OF SYSTEM OPERATION (HVACHRS) PROPOSED O.A. CFM <br />0 ...HRS/WK OF SCHEDULED FOR WARMUP/COOLDOWN (WUCD) Fan Law #2: S.P.n/S.P.o = (CFMn/CFMo)^2 <br />30 ...WKS/YR OF AIR SYSTEM OPERATION (WPY) therfore: CFMn = CFMo * SQRT(S.P.n/S.P.o) <br />See Table Above …Measured KW / Data Logger KW (FANKW) PROPOSED KW <br />...ELECTRICITY UNIT ($) COST/KWHR (ELECCOST) Fan Law #3 BHPn/BHPo = (CFMn/CFMo)^3 (BHP is proportionate to KW); CFMn=CFMo * (S.P.n / S.P.o) <br />4977 ...HEATING HRS/YR FROM WEATHER DATA (HHPY) <br />therfore: (CFMn/CFMo)^3 = KWn/Kwo <br />See Table Above ...TOTAL SUPPLY FAN CFM (CFM) <br />FAN ENERGY (KWH/YR.) <br />See Table Above …TOTAL OA CFM (OACFM) Basseline = (WINTER KW * HVACHRS * (HHPY/168)) + (SUMMER KW * HVACHRS * (52-(HHPY/168))) <br />62 ...UNOCCUPIED HRS. SPACE HEATING SETPOINT (HTSPUNOC) Proposed = (PROPOSED WINTER KW * HVACHRS * (HHPY/168)) + (PROPOSED SUMMER KW * HVACHRS * (52-(HHPY/168))) <br />27.9 ...AVERAGE O.A. TEMP. DURING HEATING SEASON (AVEDBT) <br />FAN ENERGY COST ($/YR.) <br />...$/BTU COST OF HEATING ENERGY (HEATCOST) <br />= FAN ENERGY * ELECCOST <br />0.9 …BOILER EFFICIENCY (BTU) <br />VENTILATION (BTU/YR.) <br />1.4 …CHILLER EFFICIENCY IN KW/TON (KWTON) <br />Basseline = ((BIN-DELTA T-HRS) * OACFM * 1.08) + (0.4 * (BIN-DELTA T-HRS) * TOTAL-CFM * 1.08) <br />2462 ...COOLING HRS/YR FROM WEATHER DATA (CHPY) <br />Proposed = ((BIN-DELTA T-HRS) * PROPOSED OACFM * 1.08) + (0.4 * (BIN-DELTA T-HRS) * PROPOSED TOTAL-CFM * 1.08) <br />14.7 ...COOLING WEEKS PER YEAR (CWPY) = (CHPY/168) <br />VENTILATION COST ($/YR.) <br />6.2 …COOLING ENTHALPY DELTA (ENTHALPY) 55 <br />= VENTILATION COST * HEATCOST <br />…MIXED AIR TEMPERATURE SETPOINT (MAT) <br />COOLING (KWH/YR.) <br /> <br />Basseline = (HVACHRS * CWPY * OACFM * 4.5 * ENTHALPY / 12,000) * KWTON <br />Proposed = (HVACHRS * CWPY * PROPOSED OACFM * 4.5 * ENTHALPY / 12,000) * KWTON <br />COOLING COST ($/YR.) <br />= COOLING COST * ELECCOST <br /> <br /> <br /> <br /> <br />IR Heat Modification <br />Hrs off Week Total MBH <br />7A 150 MBH 2 300 <br /> <br />7B 115 MBH 2 230 <br /> <br />0 <br /> <br />8A 115 MBH 2 230 <br /> <br />8B 150 MBH 2 300 <br /> <br />0 <br /> <br />9A 115 MBH 2 230 <br /> <br />9B 115 MBH 2 230 <br /> <br />9C 150 MBH 2 300 <br /> <br />9D 150 MBH 2 300 <br /> <br /> <br />2120 MBH <br />Weeks 24 <br />Therms Saved 508.8 <br />Savings = MBH * Weeks / 100 <br /> <br />EXHIBIT D Page 22 of 27 <br /> <br />