The Problems With Ethanol
By Justin Gardner | Related entries in EnergyDid you know…
- Ethanol has a negative energy balance. Ethanol from corn, switchgrass, and wood biomass requires 29%, 50%, and 57% more energy, respectively, to create the ethanol than the energy contained within the fuel.
- Because ethanol production requires a significant amount of energy, and most energy in the US is produced from coal, the small reduction in CO2 and other polluting emissions from burning ethanol versus gasoline will be more than offset by the power needed to produce the ethanol.
- Ethanol crops have a notoriously low energy yield per hectare. Thus, it requires a large amount of land to produce a meaningful amount of ethanol. Last year, 20% of the total corn crop was used to produce ethanol, and it offset only 1% of US oil use.
This entry was posted on Monday, June 18th, 2007 and is filed under Energy. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
June 18th, 2007 at 3:57 pm
But since the Hollywood pundits and political blowhards are pushing for ethanol, it MUST be better! They’re always right!
June 18th, 2007 at 8:22 pm
Sugar ethanol, from what I understand, is the way to go.
June 19th, 2007 at 1:44 pm
Actually switchgrass ethanol supposedly shows promise, but there needs to be a lot more research before it becomes commercially viable from a cost and energy balance standpoint.
The main reason the blowhards have been going full steam ahead for ethanol is because of the farm lobby – they love the idea of huge demand for their product that drives up price everywhere. That plus politicians have long since become used to the idea of adding 2 + 2 and coming up with 7.
June 20th, 2007 at 7:27 pm
I don’t understand how an accurate estimate of the energy balance of switchgrass can be made at this point. Frankly, it’s the most speculative of the ethanol sources. We don’t know how much ethanol will come from a given amount of switchgrass. One thing we do know is that it won’t require the kinds of levels of insecticide and other energy intensive methods that are used for corn. I really wonder about the claims.
June 21st, 2007 at 12:41 am
From what I understand about switchgrass, Jim is correct. The theoretical advantages are clear over other sources, the quantity of ethanol present in the material, and the quantity of material that can be created per unit energy, effort and land is clearly superior. The problem is, the techniques for liberating that energy efficiently are still mostly in the theoretical stages, since in switchgrass, the ethanol, though there is more of it per unit mass, is bound much more securely into the material than with corn or soy, and currently requires fairly high energy expenditure to release.
The biggest problem with ethanol is that it is generally perceived by the public (pushed by the media) as being a “green” energy, when it is in fact anything but that (as of yet). So by pushing “green” ethanol, politicians get to avoid going against their lobbyist contributors and working on the real problems, power generation plants, auto emissions, and foreign industrializing nations, among others.
In some ways, ethanol is similar to hydrogen, in that it is a fancy storefront with no store behind it…something they can trot out to make it look like they’re doing something while making minimal investment and effort, demanding no sacrifice by anyone to fix the problem.
April 9th, 2008 at 3:31 pm
[...] into the production of ethanol is far greater than the energy output once you put it into your car (ethanol from corn, switchgrass, and wood biomass requires 29%, 50%, and 57% more energy, respectivel…). Not only that, but ethanol also offers far lower mileage than either conventional gas or diesel. [...]