It depends on

1 how many stories
2 how low or how hi you want to set the temp
3 if you want all your 10+ rooms at the same temp or not
4 how good is the isolation, ie thermal resistance of your house
5 whats the temp outside
6 the rate from your utility company
7 if the utility company has good metering system
..........
.............

所有跟帖： 

• DC area。Rougly大概多少？ -trendspike- ♂ (0 bytes) () 05/24/2012 postreply 09:45:46

• 對百萬亳宅電費的確可以忽略不計。不過我可以建議一個估算模型：） -392- ♂ (141 bytes) () 05/24/2012 postreply 10:41:28

• 不能太浪費能源。 -trendspike- ♂ (0 bytes) () 05/24/2012 postreply 11:25:43

• Then SD is the best. No need for AC. -392- ♂ (0 bytes) () 05/24/2012 postreply 12:06:34