wrote:
On Sun, 25 Jul 2010 11:16:30 -0700, Steve Ackman
wrote:


It takes a LOT of energy to produce PV panels. From
what I've read,

Let's see the cite. 'Cause I've read that Elvis is alive, working at
7-eleven by day, and posting to usenet at night. :-)

a PV panel will never make up the
carbon it cost in its expected 25 year life span.

This study says 3 years for energy payback.
http://www.nrel.gov/docs/fy04osti/35489.pdf

That didn't look like MANUFACTURING payback, just purchase cost payback

This one says 6 years for
carbon payback. http://eprints.ucl.ac.uk/2642/1/2642.pdf Both numbers
expected to improve substantially.

Wayne!
You might want to read that one again...
It said "
The carbon payback for solar thermal system is 2 years,
the BIPV system has a payback period of 6 years.

Simple economic payback for both systems is over 50 years(!)

At no time did they say anything about MANUFACTURING payback!


Wayne


--

Richard Lamb