Resumen
This is a review of the literature available on data for the EROI (prior to this special issue) of the following 12 sources of fuel/energy: oil and natural gas, coal, tar sands, shale oil, nuclear, wind, solar, hydropower, geothermal, wave/tidal and corn ethanol. Unfortunately, we found that few studies have been undertaken since the 1980s, and such as have been done are often marked more by advocacy than objectivity. The most recent summary of work and data on the EROI of fuels was conducted in the summer of 2007 at SUNY ESF and appeared on The Oil Drum website and in a readable summary by Richard Heinberg. This paper summarizes the findings of that study, and also those preceding and subsequent to it where available. It also summarizes issues raised by some concerning the findings of these studies and with the calculations within. While there are many who believe that such EROI studies are critical to understanding our financial and social future there seems to be very little interest by governments and industries in supporting this research or in using or promulgating such research as has been done. We view this as critical as our main fuels are progressively depleted and as we are faced with making extremely important decisions on a very meager analytical and data base, and with few scientists trained to cut through the reams of insufficiently analyzed energy advocacy saturating our media and the blogosphere.