Is Ethanol the Answer to the Energy Dilemma?

n0xin writes "According to Fortune, "The next five years could see ethanol go from a mere sliver of the fuel pie to a major energy solution in a world where the cost of relying on a finite supply of oil is way too high." In an effort to meet fuel-economy standards, automakers already have 5 million ethanol-ready vehicles on the road. Supporters are optomistic that "we can introduce enough ethanol in the U.S. to replace the majority of our petroleum use in cars and light trucks." Are SUVs included in this category?"

Comments

Ethanol seems best

[AKAImBatman]

Ethanol would be a lot cheaper than trying to deploy hydrogen. With the hydrogen route, we have to redeploy our entire fuel infrastructure. Which isn't going to happen as long as most people drive gasoline cars. Ethanol, OTOH, can work in a standard gasoline engine with a few modifications, and can be supplied from the existing fueling stations.

With gas prices being so high, all that's standing in the way of Ethanol is this constant argument over whether or not it's energy positive or not. Of course, this completely ignores the issue that hydrogen isn't energy positive either. You need powerplants upstream to crack hydrogen, just as you'll need upstream energy to supply farming equipment. Even in Ethanol isn't energy positive (which I don't believe for a minute), it's still a better option than hydrogen.

What we really need for Ethanol to take off is a proper hybrid vehicle capable of burning both gasoline, ethanol, and various blends.

Re:Ethanol seems best

[acidblood]

What we really need for Ethanol to take off is a proper hybrid vehicle capable of burning both gasoline, ethanol, and various blends.

These are all over the place here in Brazil. Last I heard, something like 80% or 90% of small cars were sold with hybrid ethanol-gasoline engines (nicknamed Flex around here). Many shops (even small ones) already have the technology to convert an ordinary gasoline engine to a hybrid, and it isn't that expensive either.

I should remark that Brazil was a pioneer in the usage of ethanol for car fuels, but in the last decade or so it was getting out of fashion. With the advent of hybrid engines we're seeing a revival of sorts, particularly given the lower price (which unfortunately has been rising though).

For my part, I believe the future is biodiesel, not ethanol, though.

Wrong. It could.

[burne]

Ethanol made from plants will form a closed carbon-cycle. Ethanol sythesized from non-fossil sources will form a closed carbo-cycle.

Re:Still doesn't

[Rei]

Yes, we all know that Pimentel (and whatever recently graduated grad student or two he can grab up) is an anti-ethanol crusader. We also know that he's almost alone in his claims that ethanol is a net energy loser. Lastly, we also know that whenever he says it, news sources gobble it up, because it's "controversy".

It's also wrong.

First off, lets start with the fact that even if a fuel were a net energy loser, it's irrelevant. Ethanol converts a source of energy that you can't put into your gas tank into one that you can. Usually that's natural gas, but sometimes it's agricultural waste or even waste heat from other processes or power plants. The nazis converted coal to oil with horrible efficiency (using far more energy's worth of coal than they got out in gasoline), but it powered their war machine.

Ignoring that, it's not even close to a net energy loser. Everyone's studies except Pimentel comes up with this fact. Why does Pimentel get such different numbers from everyone else? He rigs the game. Instead of assuming, logically, that if ethanol demand increases, people will build more modern plants, he uses the efficiency numbers of plants from the '70s. He uses the world's worst efficiency numbers on fertilizer production. He assumes that all corn that would go toward the ethanol production comes from irrigated land (very little corn is irrigated). Some people defend this last point, saying that the corn would require new land, and any land that it would have to grow on that wouldn't need to be irrigated is already in use. This is incorrect; the corn would take the place of plants that can tolerate drier conditions, which would move into the more arid land. Overall, total irrigation use would increase, but is is incorrect to pretend that it would increase by the amount as if you had to irrigate all of the newly needed corn.

In short, Pimentel cheats to get his bad result. And he is routinely criticized for doing so. Find me an anti-ethanol study that doesn't have his name on it, and I might care.

By the way, part of the reason why ethanol is so expensive has nothing to do with energy balances, or even its production costs: it's transportation. You can't ship ethanol in much of our current oil pipeline infrastructure.

My main complaint about ethanol is simply the land issue. More farmland=More deforestation. Especially in tropical countries, this is a major issue.

Energy Return on Energy Invested

[dido]

A look at a small table of energy return on energy invested figures gives ethanol from corn a 1.3, ethanol from sugarcane something like 0.8 to 1.7 (meaning it could possibly be a net energy loser!), and ethanol from corn residues 0.7 to 1.8. Compare that with petroleum's EROEI, which is today something of the order of 23, and had once been higher than 100. Even at the maximum efficiency level, it would probably take dedicating all of the arable land in the United States to grow corn for conversion to ethanol to allow business as usual. Also, mechanized farming techniques are so heavily dependent on petroleum-based (and natural gas based) fertilizers and pesticides. Here's a good article on how to properly evaluate these schemes for alternative energy, and ethanol doesn't fare very well.

No, the only real solution to the energy crisis is to abandon the grossly wasteful American way of life, and take steps towards serious conservation efforts.

Ethanol is here now, hydrogen is a pipe dream!

[mangu]

To produce enough ethanol to sustain the US alone, would require hudreds of thousands of acres of crops.

Dude, do you have any idea at all of the number of acres of crops in the USA?

Hydrogen, on the other hand, can be produced readily in a power-plant type fashion.

Other than in science fiction, where do you have a hydrogen power plant? A hydrogen-powered car? Ethanol has been a *practical* reality for decades. My first car powered by 96% ethanol was a Brazilian 1983 Chevette. At that time, about 90% of all new cars being made in Brazil were powered by ethanol.

For the last 28 years, every single fuel station in Brazil has had ethanol pumps. Have you ever seen a hydrogen pump in any fuel station anywhere in the world? Apart from straight ethanol, all the gasoline in Brazil contains at least 20% ethanol.

There has never been a single hydrogen powered car sold commercially anywhere in the world. In Brazil, tens of millions of 92% ethanol powered cars have been sold in the last 30 years, and many more cars powered by 20% ethanol.

Do you still have any doubt on which fuel can be "produced readily"?