I have always wondered why solar panels are put on a roof. Up there, they are higher than the hot water tank (well, they are in the UK, where the temperature gets down a bit, and the storage tank is indoors), and so temperature sensors, one way valves and pumps have to be involved. It seems more logical (or am I missing something) to put the panels on ground level, or at least below the height of the hot water storage tank - the thermal syphon then does all the work with no moving parts.
Mike [EMAIL PROTECTED] 53.37N 3.02W
