Hot Water from the Sun I installed an outdoor solar-heated shower 12 years ago. It's a large box with a black tank and double-wall plastic glazing. I never shower in the house any more. Each time I feel that hot water I'm amazed and excited and delighted to think that the heat is free energy (other than the cost of the materials of the box). Plus I swear the shower feels different. Molecules of hot water heated by the sun, like rice cooked on a wood stove.
There was an excellent article on the 2008 state-of-the-art of solar water heating by Scott Gibson in a recent Fine Homebuilding: Click here for PDF