alt.energy.renewable

Mark wrote:

>... Even with no fancy heat exchanger, much of the heat of the shower drain
>water is given off by the drain pipes in to the building environment.

Not in most houses, I ween. But in some, the house heats the cold water pipe
significantly before it enters the water heater...

>... Also much of the inital heat is given up in the shower itself heating
>the walls and evaporating the water into vapor.

/

Nick