mike wrote:
I once read that it takes more energy to make, deliver, install a solar
panel than the total energy you get out of it over it's 20 year
lifetime. If that's true, (small scale PV) solar makes little sense
from an environmental standpoint.

My understanding is that improvements in the efficiency of the panels has no
longer made that true... although of course to some degree it depends on
where you end up installing the panels!

An easy way to determine whether or not the statement could be true is to
see whether or not the cost of the energy produced by the panel over its
life -- using regular market rates -- exceeds its cost. If so, obviously
the panel must be producing more energy than was requried to build it, since
all the labor and materials the manufacturer put into the panel weren't
free!