June 3, 2007

Bioethanol or Biodiesel - Which is better?

As a recent article on The Motley Fool (Fueling the Debate: Ethanol vs. Biodiesel) points out, comparing bioethanol and biodiesel is like comparing running or swimming - both are healthy exercises. But it is a good idea to know what the comparable benefits are because there are new technologies being developed all the time and the impact on biofuel infrastructure development is the key to implementation.

For example, as reported by Green Options recent algae farming research at Utah State University predicts that "oil yields of 10,000 gallons per acre could become an economically feasible biodiesel feedstock by the end or the decade. Our most productive feedstock today, the oil palm, doesn't even come close with yields of 635 gallons/acre, and is followed distantly by the U.S. standard, soy, at 48 gallons of oil/acre."

Given the other benefits of biodiesel, such an innovation could mean that more infrastructure and vehicle development should be directed toward exploiting the use biodiesel. Then again, research into cellulosic feedstock bioconversion tends to support the notion that bioethanol and biobutanol will be the superior solution.

Since the infrastructure and market for biodiesel are much better in Europe, it is likely that implementation for biodiesel would take place there. Conversely, ethanol would make more sense in North America.

Regardless, we should be putting renewable energy "trains" on a wheelhouse full of tracks because the ultimate solution will be to develop many sources of feedstock and renewable energy solutions destined for implementation throughout the world.

Fueling the Debate: Ethanol vs. Biodiesel
Which alternative fuel should investors tie their horses to?
By Jack Uldrich

According to a study published last summer in the peer-reviewed Proceedings of the National Academy of Sciences, the environmental benefits of biodiesel are substantially greater than those of ethanol. According to the report, biodiesel provides 93% more net energy per gallon than is required for its production, while ethanol generates only 25% more net energy. The study further suggested that biodiesel, when compared with gasoline, reduced greenhouse emissions by 41%, while ethanol yielded only a 12% reduction. From these viewpoints, it would appear that biodiesel is the clear winner.

If only it were that easy. From a land-use and agricultural-efficiency perspective, ethanol appears to be the better choice. That's because an estimated 420 gallons of ethanol can be produced per acre of corn versus only 60 gallons of biodiesel per acre of soybeans. In more practical terms, this means that if the production of biodiesel were ever to increase greatly, the cost of soybean oil would rise significantly.

What's so exciting about cellulosic ethanol is that it has the potential to offer a very high net-energy impact. It can also be produced from feedstocks that use little to no fertilizer. These sources are abundant and aren't major sources of food -- and thus won't drive up food prices as we've seen as of late with corn prices. As an added benefit, it's believed that as the technology improves, the amount of ethanol produced per acre can increase significantly. Some experts have estimated that the figure could reach as high as 2,700 gallons per acre by 2030.

In short, cellulosic ethanol may very well have the environmental benefits of biodiesel and the agricultural efficiency of corn ethanol, but it can also potentially bring additional benefits to the table.

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