Shanghai
Energy Savings % Indoor Vs. Window R/F
A/C is Off 
Excluding Summer Energy Savings
Definition of Columns in the table: 
B = Average Outdoor temperature (temperature of Window R/F's Condenser).   
C = Average Indoor Temperature, 70 F or higher (temperature of Indoor R/F's Condenser). 
D = Average temperature inside the R/F (set constant at 29 F). 
Ti = C - D = Temperature difference between the Indoor R/F's evaporator and condenser. 
Tw = B - D = Temperature difference between the Window R/F's evaporator and condenser.  
G = Energy Savings % assuming that both R/Fs have the same COP (efficiency).  
G = (Ti - Tw) / Ti   Unlike Column H, it does not include the higher efficiency of  window R/F. 
H = Energy Savings % taking into account the higher COP (efficiency) of the window R/F. 
H = 1 - (Tw x Tw) / (Ti x Ti)  Unlike column G, it includes the higher efficiency of window R/F. 
Fahrenheit B C D Ti Tw G H
JAN 41 70 29 41 12 71% 91%
FEB 42 70 29 41 13 68% 90%
MAR 49 70 29 41 20 51% 76%
APR 59 70 29 41 30 27% 46%
MAY 69 70 29 41 40 2% 5%
JUN 75 75 29 46 46 0% 0%
JUL 83 83 29 54 54 0% 0%
AUG 82 82 29 53 53 0% 0%
SEP 76 76 29 47 47 0% 0%
OCT 67 70 29 41 38 7% 14%
NOV 56 70 29 41 27 34% 57%
DEC 46 70 29 41 17 59% 83%
Average Energy Savings %      27% 39%
Exact same as above except in Celsius
Celsius B C D Ti Tw G H
JAN 5 21 -2 23 7 71% 91%
FEB 6 21 -2 23 7 68% 90%
MAR 9 21 -2 23 11 51% 76%
APR 15 21 -2 23 17 27% 46%
MAY 21 21 -2 23 22 2% 5%
JUN 24 24 -2 26 26 0% 0%
JUL 28 28 -2 30 30 0% 0%
AUG 28 28 -2 29 29 0% 0%
SEP 24 24 -2 26 26 0% 0%
OCT 19 21 -2 23 21 7% 14%
NOV 13 21 -2 23 15 34% 57%
DEC 8 21 -2 23 9 59% 83%
Average Energy Savings %      27% 39%
Exact same as above except in Kelvin
Kelvin B C D Ti Tw G H
JAN 278 294 271 23 7 71% 91%
FEB 279 294 271 23 7 68% 90%
MAR 282 294 271 23 11 51% 76%
APR 288 294 271 23 17 27% 46%
MAY 294 294 271 23 22 2% 5%
JUN 297 297 271 26 26 0% 0%
JUL 301 301 271 30 30 0% 0%
AUG 301 301 271 29 29 0% 0%
SEP 297 297 271 26 26 0% 0%
OCT 292 294 271 23 21 7% 14%
NOV 286 294 271 23 15 34% 57%
DEC 281 294 271 23 9 59% 83%
Average Energy Savings %      27% 39%
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