Hybrid Car – More Fun with Less Gas

how much power does it take to produce a solar panel? - Page 5

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Posted by whit on May 17, 2009, 1:42 pm
On energy payback, newer technology is creating quicker payback,
Evergreen's drawn string silicon cells use muchless energy (and
silicon) and have a quicker energy payback than other cells.

The calculations on energy payback are for grid connect systems where
100% of the energy is added to the system (which is only 50% effiecent
it's self)

I live off gris so the system cost payback is of intrest to me, but
agreed it's a seperate issue, though they are related.

In my case it is cost effective with the grid running in front of my
house! Our electric coop has a $5 a month user fee before you buy any
electric, as I use only 2-4 Kilowatts a day most days and max out in
summer with 6-7, when I run an AC.

My system will pay back it's $ cost in @12years (I installed my self,
built and maintained my self or this would several years longer) As to
the system energy payback, it likely will never make due to the
batteries, though I may if I continue with an under sized battery bank
(I was unwilling to toss the year old, 4 golf cart batteries I was
using when I built my small well insulated cabin and it's worked out
OK though I can only run the AC for a 2-3 hours at night. I'm on the
4th year now and I hope to make it through the summer.)

In the end the great savings for me is learning to use energy
economically, even building the 6" thick walled cabin in the shade,
using an on demand gas water heating system that lives outside. I even
built a seperate kitchen/bathroom to keep the heat from inside my

One thing that I find interesting is often the usefulness of solar
panels is only considered their under warranty period. I have 3 French
photowatt panels made in the late 70's that were producing @ 80% of
their rated value 3 years ago when I added panels to run AC. Not sure
if we aren't looking at the wrong thing on the production end if the
string tech of the evergreen panels will have a shorter life (I think
they expect 30-40 year from thier panels)

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