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The Strange Energy Budget of Ethanol Production
joeflies writes "The San Francisco Chronicle published an article regarding research on how much fuel is required to make Ethanol. The results indicate that it make take 6 times more energy than the end product delivers."
Compare this to gasoline and hydrogen and you've got yourself a real article.
"Taking grain apart, fermenting it, distilling it and extruding it uses a lot of fossil energy," he said. "We are grasping at the solution that is by far the least efficient.".
He ignores the fact that, if we wanted to, we *could* arrange the production chain so that it was not dependent on fossil fuel. You could build your farming and fermentation facilities to use solar or hydro power, for example.
Sure, it's fossil-intensive *now*. But it's also not a major energy source yet. If we needed to we could clean up the energy chain - there's no part of the process that requires fossil fuel sources.
-EvilMagnus
Don't drive gas guzzlers. Don't drive unless you need to. Maybe while you're at it you might as well bike or walk some places and lose some weight reducing the burden on health care.
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Go canucks, habs, and sens!
sure, as long as there's oil, ethanol doesn't really look efficient or affordable except as a fuel oxygenator. but if the oil reserves were to run out sometime soon, ethanol could be poured into most of our existing infrastructure and ease the transition. that's why it's important -- not because it's inherently superior to petroleum, but because it can be manufactured (from scratch) much more quickly.
Did you even read the article? You're missing the entire point! If the oil reserves run out you won't be able to get any ethanol to pour in your car either! Corn based ethanol requires far more energy in its production than it is capable of producing itself, almost all of which comes from fossil fuels. In fact, according to this article producing one unit of energy in ethanol requires 2.3 units of energy to produce. That's gotta come from somewhere, and right now its going to be fossil fuels.
The bottom line is that ethanol programs are, right now, nothing more than another farm subsidy. The politics such programs are beyond the scope of this article, but suffice it to say that touting ethanol as the solution to our energy problems is at best disingenuous, dishonest, and a potentially disasterous diversion from the real technologies we are going to need to maintain our current life styles in the future.
Oh, I almost forgot. Using sugar-based production techniques developed over the past 20 years, Brazil currently manufactures huge quantities of ethanol and sells it on the international market for approximately $30-$35 per barrel. Most of the ethanol the US imports comes from Brazil. If producing it was so inefficient, I'd expect it to be a lot more expensive, wouldn't you? Compared with current oil prices (>$50/barrel?), and the potential for efficiently producing ethanol from agricultural waste in the next 5-10 years, I'd say the case for ethanol's looking pretty good.
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Do keep in mind though that not all energy is created equal. If it takes some number of units of heat and electricity, we needn't assume they come from oil. Really, studies like this need to break things out into "portable" and "non-portable" energy forms. If it uses more portable energy than it produces, then it's a loser. If it uses less portable energy, but some additional amount of non-portable energy then it could still work out OK.
At the end of the day, we don't make electricity out of oil, so a process that uses electricity and produces oil/ethanol might be useful if we need oil, and have electricity to burn.
This is one of the primary justifications for things like widespread solar and nuclear power sources. Though they don't help our dependence on oil directly, by giving us a limitless/very large source of electricity, we are more able to undertake processes that consume electricity but produce oil/ethanol, helping to reduce the constraints on oil supplies.
Another good example of this is Hydrogen. Hydrogen production is important, but not because you'll run your car on it. It is used in all sorts of industry (including oil refining), and can easily be used with Thermal Depolymerization (TDP) to produce oil from all sorts of useless trash, literally. We currently make hydrogen from natural gas, so it's not worth it to use that hydrogen to make oil, but if we could make it from something else, then the whole equation changes. Lots of industry that burns natural gas or coal, or uses it chemically, could use the produced hydrogen instead, and the natural gas could be used to power vehicles, or even be directly converted into oil.
It's very much interconnected. Saving electricity doesn't really help here, as we would still be converting coal to oil, which isn't really so helpful from an environmental standpoint. Dramatic new sources of power, however, like widespread solar or nuclear allows us to convert effectively limitless energy to an oil like form, and would change things dramatically.
Once again, life is more complicated than what passes for journalism these days.