Doug gets down with the numbers

My colleague Doug Fox just posted what I thought was the best post yet on the Terra Haus blog.

Apparently the expected solar gain is 7.8 m BTUs/year, which Doug states is 1/2 a cord of wood.

Let's check his math. According to my friendly local forest products website, there's 24 million BTUs of heat per cord in ash firewood -- the most common hardwood used for fuel in Maine. But with even the best modern wood-burning space heaters you'll only get 85% of that heat into the house. So 0.5 times 0.85 times 24 million is 10.2 m BTUs, a little more than 7.8, but close enough for government work.

I think he's in the ballpark.

I like numbers, but I really like those numbers.

http://terrahaus.wordpress.com/2011/08/05/431/