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Lynd 16 (1:36)
Topic(s): Biofuels
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Video Transcript
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.
