http://blog.maxdunn.com/articles/2009/09/10/solar-pv-energy-payback en-us 40 Max Dunn's Blog <p>Some people claim that more energy goes into making a solar photovoltaic (PV) panel than it will ever produce. While years ago that may have been the case, it certainly isn&#8217;t true any longer.</p> <p>The <a href="http://www.nrel.gov/docs/fy04osti/35489.pdf">US Department of Energy looked at several studies</a> and concluded that multi-crystalline PV has an energy payback of less than 4 years and this will likely go down to below 2 years soon. Thin-film technologies have an even shorter payback period. With an estimated 30-year life, solar PV is actually a very good energy investment!</p> Thu, 10 Sep 2009 14:25:00 -0700 urn:uuid:6b558092-e3e8-4936-97fd-582d41103813 Max Dunn http://blog.maxdunn.com/articles/2009/09/10/solar-pv-energy-payback Sustainable Energy <p>According to the handy chart, a current-technology polycrystalline module with the standard aluminum frame has a net energy ratio of about 8 to 1. Not spectacular, but not quite as bleak as the 1 to 1 (why bother) claims of the post-carbon survivalist types. A thin-film module with &#8220;anticipated&#8221; efficiency and no frame is projected to be closer to 30 to 1, and an anticipated unframed polycrystalline is roughly 13 to 1. Not the glory days of 100 to 1 oil gushing out the ground all by itself, but not wildly mismatched from today&#8217;s costly fossil fuel, right?</p> <p>Also very worthy of note: the racking systems, especially ground-mount installations (probably because of concrete foundations), can cut these net energy ratios by a third to a half in the more optimistic anticipated PV technology cases.</p> Thu, 10 Sep 2009 16:52:06 -0700 urn:uuid:0f2c8fc6-3ecd-4839-b590-7dad3c785f6d http://blog.maxdunn.com/articles/2009/09/10/solar-pv-energy-payback#comment-792