Just some nitpics... >> Is solar thermal water heating *still* more efficient?
> Suppose you have a limited roof area that can only collect 1 KWH of energy. > PV cells might convert that into 150 watts of electricity. A solar water heat > might convert it into 300 watts of heat in your water heater. Which is more useful to you? But using a heatpump water heater can convert that 150W of electricity to the equivalent of 450 Watts (BTU's) due to its Coeficient of performance being 3 to 1. > But most roofs are so large that the amount of solar energy available is "limitless". I disagree. Almost everyone is roof limited. They use more energy than they have roof. _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
