Posted by Jeff on December 11, 2003, 5:53 am
Does anyone have any links to information on the required amount of energy
needed to manufacture a solar cell? Google is not being much of a help under
the terms I searched for.
I'm curious to actually see how long it has to be operated before we get a
net gain of energy from it.
Posted by Bob Peterson on December 11, 2003, 12:08 pm
The answer is - it depends on how you do the calculations. Most of the
manufacturer's sites have some information on this type of thing, but there
is little detail on just how they made the calculations so there is no way
to know if they have calculated it in an accurate way or have done the
calculations strictly for marketing purposes.
Posted by Fred B. McGalliard on December 11, 2003, 3:21 pm
This is way harder than it sounds. It depends very much on how the cells are
made, what kind of structure they are assembled into, whether you count
storage as part of the "system", whether you include the costs of
advertising, and how you add costs for which contributions from a community
that is still using gasoline for transportation and mostly coal and natural
gas for electricity. Then you have to consider the range of solar insolation
available as well as any waste time. I think the numbers ranging from 6 mo
to never in a pig's eye, with a peak around 2 years, may all be valid based
on different ideas of how to add all this up.
Posted by H. E. Taylor on December 11, 2003, 11:41 pm
If you do come across such data, please be sure to post it.
Such info is rare. The reason is partly politics, partly
problem definition. I took a stab at the question here:
12) What is the Payback Time of PV?
"Good design is clear thinking made visible." -Edward Tufte
Energy Alternatives: http://www.autobahn.mb.ca/~het/energy/energy.html
H.E. Taylor http://www.autobahn.mb.ca/~het/
Posted by Jim Avery on December 12, 2003, 1:06 am
The following link is detailed article on the subject of energy payback time
for PV modules written by some folks that are well respected in the
industry. Answer is 3.3 years for Silicon.