> I pay $0.13 per kWh in my town. So assuming $15/month, you are using 115kWh, which is 392kBTU of heating energy. It takes about 83kBTU to heat 200gal of wa

> I pay $0.13 per kWh in my town. So assuming $15/month, you are using 115kWh, which is 392kBTU of heating energy. It takes about 83kBTU to heat 200gal of water from 50F to 100F, which would be like 5 full heat ups from 50F. Of course there are the other convolved factors you mentioned (insulation).