I did not make an estimate. My source of information was from a January 2007 article in the Independent (UK): <http://news.independent.co.uk/environment/article2144575.ece>
I'm pleased to hear the return on investment for solar cells (photovoltaics) is so quick! It is a shame this isn't more widely known and that the incorrect 60-year rate of return continues to be published in newspapers. Hearing of a 60-year rate of return is a real downer: to the industry and to those who are looking for alternative energy. CL La Follette, Doug J - SOS wrote: > From: David Pimentel [mailto:[EMAIL PROTECTED] > Sent: Sunday, February 04, 2007 5:15 AM > To: La Follette, Doug J - SOS > Subject: Re: FW: Ethanol (in)efficiency wind, food, solar, and SUVs > > > Doug: > > > You sent me a note stating Bridgman estimated that it takes 60 = > years to get a replacement on investment. This is incorrect. For the = > energy replacement, it takes only 3 to 4 years. It is expensive to = > operate about 25=A2 per kWh. See Pimentel et al., 2002. > > > Best regards, > David > > -------- Original Message -------- > Subject: Re: Ethanol (in)efficiency > Date: Sun, 4 Feb 2007 00:20:20 +0800 > From: Cara Lin Bridgman <[EMAIL PROTECTED]> > Reply-To: Cara Lin Bridgman <[EMAIL PROTECTED]> > To: [email protected] > > I thought one future problem with solar cells is that they require oil > to produce. I recently read somewhere (here?) that solar cells require > about 60 years of use before you get a return on your investment. Maybe > with full accounting... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Cara Lin Bridgman P.O. Box 013 Phone: 886-4-2632-5484 Longjing Sinjhuang Taichung County 434 Taiwan http://megaview.com.tw/~caralin/ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
