[SGVLUG] Off-topic - home guerrilla solar systems

[David Lawyer]

On Mon, Feb 19, 2007 at 11:42:12PM -0500, Robert Leyva wrote:
> Decided to really look into getting a solar power system to reduce my
> electrical load, even if it was just for the principal of the matter.
> 
> Found out that there are some kits that provide about 100W AC for around $1k.

Are you sure that it actually saves energy?  It takes a lot of energy
to make solar-voltaics and no one knows how much.  That's partly
because we don't know how to account for human energy.  I don't mean
just metabolic energy but all the fuel energy to provide food,
clothing, shelter, education, and recreation to workers and enable
them to reproduce.  It all needs to be sustainable.

I'm drafting an article on human energy accounting using feedback
models like in electronic amplifiers.  Consumer goods are output and
they go to support workers whose embedded energy becomes an input to
production.  It turns out that the flow of this embedded fuel energy
in humans can often be greater than the flow of fuel energy into the
economy.  It can be greater because it circulates via feedback and
isn't a final output nor a fuel input.  Thus one shouldn't neglect
human energy flows in estimating the energy content of goods and
services, but unfortunately most everyone does.

It would take many more paragraphs to explain all this and I'm still
not sure about some aspects.  Anyone willing to read over my article
on this when I get it done?

			David Lawyer