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Lynd 16 (1:36)
Topic(s): Biofuels
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There's this notion that it takes more fossil fuel energy to put into making ethanol than you end up using, and therefore, why this may line some people's pockets, the argument often goes: how beneficial can it really be to providing a large-scale energy source, if it takes more than it yields? As currently practiced, almost all evaluations of corn ethanol show that it is somewhat— has a somewhat favorable energy balance. That is, you get on the order of, for one part of liquid fuel produced, you would put in some, depending on who does the calculation, maybe 3/4 of a part of liquid fuel in. And that is a pretty marginal benefit, especially because you need a great deal of land if you only have a 25 percent net return.

For cellulose, or cellulosic biomass, that ratio is more like 10:1 of energy out to energy in. And in fact, for petroleum refining today, it's about 7:1 and that's a pretty mature industry. And so if you get 10 energy units out for every energy unit in, that's a pretty good deal. And, you know, it's funny how the perception of uncertainty or disagreement persists, but in my opinion, there simply is no informed disagreement on the subject of the net energy balance of cellulosic ethanol being profoundly favorable.



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