I wouldn't trust my earlier response too far, on EROEI of renewables.
I usually do those back-of-the-envelope calculations, made famous by
Enrico Fermi at Los Alamos; I hate being associated to nuclear
destruction, but hey, it's my training.
Instead, go for more detailed and empirical studies, such as Knapp
and Jester 2000. Keep in mind they're studying PV modules made and
used in California, so if they say 9 to 17 times EROEI, think 4 to 10
times for our area, keeping in mind a bit further cut for the balance
of system:
http://www.ecotopia.com/apollo2/knapp/PVEPBTPaper.pdf
The first paragraph of their conclusion to a thorough study:
"The payback time for today's production photovoltaic technology is
substantially less than its expected lifetime. With a module lifetime
of 30 years, the panels analyzed here will produce nine to seventeen
times the energy used in its production. The effects of the other
components of a photovoltaic system can be significant relative to
the module payoff itself, most notably in systems requiring
batteries. Including life-cycle energy balances in both module
production and BOS design are necessary to claim sustainability."
-Shawn
_______________________________________________
For more information about sustainability in the Tompkins County area, please
visit: http://www.sustainabletompkins.org/
RSS, archives, subscription & listserv information for:
[email protected]
http://lists.mutualaid.org/mailman/listinfo/sustainabletompkins
Questions about the list? ask [email protected]
free hosting by http://www.mutualaid.org
