[ExI] Small scale solar payback time (was Re: Planetary defense)

[Eugen Leitl]

On Thu, May 12, 2011 at 04:14:12PM -0700, Keith Henson wrote:
> On Thu, May 12, 2011 at 3:29 PM, Kelly Anderson <kellycoinguy at gmail.com> wrote:
> > On Thu, May 12, 2011 at 9:49 AM, Keith Henson <hkeithhenson at gmail.com> wrote:
> >> Ground solar currently has an energy payback time of 2-4 years.
> >
> > Where does this come from? It is certainly not the case for small scale solar.
> 
> ^ "What is the Energy Payback for PV?" (PDF). National Renewable
> Energy Laboratory. http://www.nrel.gov/docs/fy05osti/37322.pdf.
> Retrieved 2008-11-24.
> 
> If you say that's not the energy payback time, what is?  I.e., how
> much energy does it take to make and install PV vs the average power
> production per day?

"Life cycle assessment and energy pay-back time of advanced photovoltaic modules: CdTe and CIS compared to poly-Si", by Marco Raugei, Silvia Bargiglia and Sergio Ulgiati at Energy Volume 32, Issue 8, August 2007, Pages 1310-1318

http://www.civil.uwaterloo.ca/beg/Downloads/NREL_PV_Embodied_Energy.pdf

EROEI of >40, energy payback time (which is not relevant,
EROEI integrates over lifetime, energy payback doesn't
contain total energy harvested over lifetime) of under a year.

"Update of PV energy payback times and life-cycle greenhouse gas emissions" V. Fthenakis, H.C. Kim, M. Held, M. Raugei and J. Krones, 24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany

etc.

I think SPS will have a pretty tough competitor, as in 10-20
years both the ROI and EROEI will be untouchable.

-- 
Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org
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