Alternative Power sources - Re: has anybody compiled a list of rapid return energy saving measures?

Author

Re: has anybody compiled a list of rapid return energy saving measures?

chrisvillar@hotmail.com

2005-08-17, 11:21 am

>
> If it takes 'quite a few gallons' to flush out the cold water then you
> are using pipes too big, and probably metal pipes as well. If you use
> 1/2" plastic pipe there is little cold water to flush out and little
> thermal mass to heat.

According to my calculations, a 1/2" I.D. pipe holds one gallon per 98
linear feet of pipe. So I was way off in my guess that I waste 4
gallons of water in the morning. The run from my water heater to the
bathroom is no more than 40'. So I am wasting about 40% of one gallon.

Check my calcs:

1 gallon = 231 cubic inches

www.onlineconversion.com

cross sectional area of a 1/2" I.D. pipe = pi * r^2 = 3.14 * 0.25 *
0.25 =
0.19625 square inches

231 cubic inches / 0.19625 square inches = 1177 inches = 98 feet

A honkin' 1" pipe would be one gallon per 24.5'. Even with that huge a
pipe, I'd waste less than half the volume of water I guessed in my post
yesterday.

LinkBot