Friday, January 19, 2007

Love of Diesel

I’ve been in conversations about alternative fuels recently. Folks say that methanol and ethanol as gasoline substitutes may lead to competition with food crops for freshwater and land space. Hydrogen is probably not feasible as a fuel either because it is expensive to make, and takes so much space to store.

Vin Diesel is a strapping young actor, but even his energy output is a mere drop in the bucket compared to our nation's needs.

Here is what I think people should be talking about as alternative fuel: biodiesel. Today's Diesel engines will run on biofuel with little or no alterations. Indeed, Rudolf Diesel (1858-1913) designed his engine to run on vegetable oils, stating the words “peanut oil” as he started his demonstration engine at the 1900 Paris Exposition, according to this MSN MoneyCentral article on Diesel.

Willie Nelson’s Biodiesel Website explains how vegetable oil can be modified to be used in existing Diesel engines. Already, there are biodiesel pumps around the country, and you can drive your existing Diesel car, with no modifications, to them and fill up.

But still, there is the question of where the vegetables come from to produce enough Diesel fuel to make it a significant alternative to petroleum fuel. As with ethanol or methanol production, land and water don’t exactly grow on trees.

In looking for a response to this, one might inquire about plants that grow in saltwater. Do they have oil like land-grown vegetables? Willie Nelson’s website does make brief mention of algae, after all.

These researchers at JMU in Virginia are experimenting with saltwater algae as a source for fuel oil. They say that algae can have up to 50% oil by weight, far better than soybean’s 20%. (I don’t know if by “soybean” they really mean just the bean, or the whole plant.) And algae grows and produces oil year-round, while land crops produce oil only in their seeds, and only for a small part of the year.

Still, you may say, you want numbers. You want facts. We are a long way off from paying algae, rather than Middle Easterners, for our fuel. And really now, come on, now much algae will it take to make enough fuel to run all our cars? Would we need to cover the Earth with algae? And who says you can trust algae not to support terrorism once it starts to get a piece of the cheddar? After all, think of the ties algae has to biological agents. If you think Saddam was bad . . .

Folks, I give you theUniversity of New Hampshire Biodiesel Group. It’s got more numbers than Dutch Schultz’ racket; better figures than the Milan Fashion Show. (Hey, Dress a Day, there are weeks worth of dresses there! By the way, I love your “Secret Lives of Dresses Vol. 10. This entry shows me the true potential of a web site which features a new dress every day. I can now subscribe.)

This article cites the research of the Aquatic Species Program, from 1978 to 1996, under the National Renewable Energy Laboratory, a division of the Department of Energy. It talks about growing algae in saltwater ponds in deserts, spaces that nobody would mind using for this purpose (Algae?! not in MY backyard). Here is an extensive quote from the article.

“. . .to replace all transportation fuels in the US, we would need 140.8 billion gallons of biodiesel, or roughly 19 quads (one quad is roughly 7.5 billion gallons of biodiesel). To produce that amount would require a land mass of almost 15,000 square miles. To put that in perspective, consider that the Sonora desert in the southwestern US comprises 120,000 square miles. Enough biodiesel to replace all petroleum transportation fuels could be grown in 15,000 square miles, or roughly 12.5 percent of the area of the Sonora desert (note for clarification - I am not advocating putting 15,000 square miles of algae ponds in the Sonora desert. This hypothetical example is used strictly for the purpose of showing the scale of land required). That 15,000 square miles works out to roughly 9.5 million acres - far less than the 450 million acres currently used for crop farming in the US, and the over 500 million acres used as grazing land for farm animals.”

But, the article says, it would be better not to concentrate the algae ponds in one place, but to spread them around the country. One reason for this is, the ponds could be constructed where agricultural waste is accumulated and could be used as food for the algae. I suppose the sea water would have to be pumped to these locations.

Regarding costs, here is another long quote citing another study of a certain kind of algae pond construction. I love how the authors double the cost of pond construction, to give a cautiously pessimistic estimate:

“In ‘The Controlled Eutrophication process: Using Microalgae for CO2 Utilization and Agricultural Fertilizer Recycling’, the authors estimated a cost per hectare of $40,000 for algae ponds. In their model, the algae ponds would be built around the Salton Sea (in the Sonora desert) feeding off of the agricultural waste streams that normally pollute the Salton Sea with over 10,000 tons of nitrogen and phosphate fertilizers each year. The estimate is based on fairly large ponds, 8 hectares in size each. To be conservative (since their estimate is fairly optimistic), we'll arbitrarily increase the cost per hectare by 100% as a margin of safety. That brings the cost per hectare to $80,000. Ponds equivalent to their design could be built around the country, using wastewater streams (human, animal, and agricultural) as feed sources. We found that at NREL's yield rates, 15,000 square miles (3.85 million hectares) of algae ponds would be needed to replace all petroleum transportation fuels with biodiesel. At the cost of $80,000 per hectare, that would work out to roughly $308 billion to build the farms.

The operating costs (including power consumption, labor, chemicals, and fixed capital costs (taxes, maintenance, insurance, depreciation, and return on investment) worked out to $12,000 per hectare. That would equate to $46.2 billion per year for all the algae farms, to yield all the oil feedstock necessary for the entire country. Compare that to the $100-150 billion the US spends each year just on purchasing crude oil from foreign countries, with all of that money leaving the US economy.“

Okay, so it’s just a study. But as far as I can tell, it makes biofuel production from algae look like something to be explored. It is an alternative fuel source, not only to petroleum, but also to biofuels grown from existing land crops, which may a dubious prospect.

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