View Single Post
Old 03-24-13, 07:48 AM   #10
MN Renovator
Less usage=Cheaper bills
MN Renovator's Avatar
Join Date: Nov 2010
Location: Minneapolis, MN
Posts: 939
Thanks: 41
Thanked 116 Times in 90 Posts

I think this is the correct math, let me know if I'm off-base.

1.08*40CFM*40 degree difference(70 inside 30 outside)=1728BTU/hr*24 hours=41,472BTU per day.
That's 8 hours of an electric 1500 watt space heater running or about $1.20 at 10 cents per kwh.
About .4 therms or $.40 if your total gas costs are a dollar per therm. So if your average outdoor temperature for a month is 30 degrees outdoors your rough number would be $12.40 if you are paying $1 per 100k BTU of natural gas or for electric resistance heating it would be about $37, about a third of that cost with a heat pump.

The bigger issue that I see is the moisture content that you might be dragging into the house in the summer if your dew point gets over 55 degrees.
MN Renovator is offline   Reply With Quote
The Following User Says Thank You to MN Renovator For This Useful Post:
Ryland (03-24-13)