Interesting biofuel article

Khannie

Interesting biofuel article:

(note that it doesn't mention recycled oil for use in biodiesel....only virgin products)

ITHACA, N.Y. -- Turning plants such as corn, soybeans and sunflowers into fuel uses much more energy than the resulting ethanol or biodiesel generates, according to a new Cornell University and University of California-Berkeley study.

"There is just no energy benefit to using plant biomass for liquid fuel," says David Pimentel, professor of ecology and agriculture at Cornell. "These strategies are not sustainable."

Pimentel and Tad W. Patzek, professor of civil and environmental engineering at Berkeley, conducted a detailed analysis of the energy input-yield ratios of producing ethanol from corn, switch grass and wood biomass as well as for producing biodiesel from soybean and sunflower plants. Their report is published in Natural Resources Research (Vol. 14:1, 65-76).

In terms of energy output compared with energy input for ethanol production, the study found that:
-- corn requires 29 percent more fossil energy than the fuel produced;
-- switch grass requires 45 percent more fossil energy than the fuel produced; and
-- wood biomass requires 57 percent more fossil energy than the fuel produced.

In terms of energy output compared with the energy input for biodiesel production, the study found that:
-- soybean plants requires 27 percent more fossil energy than the fuel produced, and
-- sunflower plants requires 118 percent more fossil energy than the fuel produced.

In assessing inputs, the researchers considered such factors as the energy used in producing the crop (including production of pesticides and fertilizer, running farm machinery and irrigating, grinding and transporting the crop) and in fermenting/distilling the ethanol from the water mix. Although additional costs are incurred, such as federal and state subsidies that are passed on to consumers and the costs associated with environmental pollution or degradation, these figures were not included in the analysis.

"The United State desperately needs a liquid fuel replacement for oil in the near future," says Pimentel, "but producing ethanol or biodiesel from plant biomass is going down the wrong road, because you use more energy to produce these fuels than you get out from the combustion of these products."

Although Pimentel advocates the use of burning biomass to produce thermal energy (to heat homes, for example), he deplores the use of biomass for liquid fuel. "The government spends more than $3 billion a year to subsidize ethanol production when it does not provide a net energy balance or gain, is not a renewable energy source or an economical fuel. Further, its production and use contribute to air, water and soil pollution and global warming," Pimentel says. He points out that the vast majority of the subsidies do not go to farmers but to large ethanol-producing corporations.

"Ethanol production in the United States does not benefit the nation's energy security, its agriculture, economy or the environment," says Pimentel. "Ethanol production requires large fossil energy input, and therefore, it is contributing to oil and natural gas imports and U.S. deficits." He says the country should instead focus its efforts on producing electrical energy from photovoltaic cells, wind power and burning biomass and producing fuel from hydrogen conversion.

The web version of this story, with accompanying photos, is available at http://www.news.cornell.edu/stories/July05/ethanol.toocostly.ssl.html
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Mailman

Perhaps it is obvious but I don't understand - how can you go in to Lidl and purchase a litre of vegatable oil for 60c if it is so expensive to produce. Are the vegatable oil manufacturers being subsidised. Vegetable Oil is even cheaper if bought in bulk.

Capt'n Midnight

Mailman wrote:

Perhaps it is obvious but I don't understand - how can you go in to Lidl and purchase a litre of vegatable oil for 60c if it is so expensive to produce. Are the vegatable oil manufacturers being subsidised. Vegetable Oil is even cheaper if bought in bulk.

AFAIK the CAP subsidises rape seed oil and similar stuff.

I can't find a price on Ag. Diesel / Marked Gas Oil
http://www.irishtrucker.com/topics/lubricants/archive.asp - lots of illegal use of VAT free Diesel.

I've posted before that you need to use the corn straw for heating to get a positive energy balance - or simply redefine Green Diesel to exclude any Diesel where more Fossil fuels than renewables are used in it's production

bonkey

I'm curious as to how the author can claim (regarding bio-ethanol) that it is not a renewable energy source. How is it not renewable?

jc

Capt'n Midnight

bonkey wrote:

How is it not renewable?

It's not fully renewable if you use fossil fuels to produce it. If the energy content of the fossil fuel used is higher than the bio-fuel generated then it's a complete waste of resources, and you also get more CO2 into the bargin.

ednwireland

this reminded me of an article i saw
http://www.eclipsenow.org/Facts/alternateenergy.html
which basically says the same thing - the amount of oil required to make lternative energy isn't factored into the equation. i.e construction transport, the wires i'm sure need oil etc. etc.
i don't think it means we shouldn't be looking or using these sources of energy but more rigourous assesments are needed. you can't just say because the source is renewable its good. my own opinion is the gov. should be doing much much more to reduce energy consumption but that doesn't fit with privatising the esb now does it.