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Bio-diesel Made from Sewage
tito writes "A New Zealand company has successfully turned sewage into modern-day gold. New Zealand Herald is reporting that a Marlborough-based Aquaflow Bionomic yesterday announced it had produced its first sample of bio-diesel fuel from algae in sewage ponds.
It is believed to be the world's first commercial production of bio-diesel from 'wild' algae outside the laboratory - and the company expects to be producing at the rate of at least one million litres of the fuel each year from Blenheim by April."
The UNH Biodiesel Group calculated that algae farms in the Mojave Desert alone could supply enough fuel to replace all the gasoline used in the USA. That was just an example to show the land-area requirements. In practice you would want algae cultivation spread out around the country. (The availability of waste feedstocks around the country is one reason.)
I like biodiesel as a long-term solution for several reasons. . .
Because an air-breathing engine draws much of its "fuel" mass from the air, it starts with a large advantage in energy density, and it will be hard for other energy sources -- batteries, supercapacitors, flywheels -- to ever compete.
Unlike hydrogen, we already have the infrastructure in place to handle, store and distribute biodiesel, and millions of vehicles that can already run off it, and the capacity to economically produce millions more of them.
Producing it from algae mimics the process by which petroleum originally formed, over the eons. It might seem unrealistic to produce enough biofuel on a year-by-year basis to replace the *millions* of years worth of petroleum that we routinely burn without thinking anything of it. . . But the natural processes that created petroleum were haphazard, and hardly what anyone would call efficient.
If you replace haphazard processes with specially selected (maybe genetically engineered) strains of algae kept in controlled conditions, with concentrated feed of nutrients and sunlight, the production capacity could be immense. So yeah, I think it can be done.
We might not ever see dirt-cheap fuel again, but I'm optimistic that we can come up with petroleum alternatives at a level that allows our economy and industry to keep on functioning.
I think you mean switch to sugar cane since it's 8x more efficient than corn. Corn is what we already have, and sugar is what Brazil is using right now.
According to the UNH study and Wikipedia, the yield of algae farms is about 5000 to 20,000 gallons per acre of pond per year. This number varies mostly due to the pond conditions, strain of algae used, and oil collection method employed.
However, it is worthwhile to note that even the low end (5000 gallons per acre per year) is over 100 times better than soybeans (50 gallons per acre per year) or rapeseed (about 120 gallons per acre per year)... which are the two dominant crops providing biodiesel in America and Europe today.
To supply the entire US fuel needs would require as little as 0.3% of US land area to be covered by algae ponds. This translates to about 28,000 square kilometers, or about 11,000 square miles. To put this in perspective, that is about 1/8th the size of Kansas... and well less than the area devoted to Soybeans currently.
Self-referential Sigs are cool on /. these days...
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I'm not sure I see your point. You're saying we'd need to find 26 municipalities with wastewater treatment plants to convert to algae farms, which would be part of the requisite wastewater treatment solution as well as producing fuel, in order to match one plant which requires farmers to go out and actively produce feedstock for at added expense? That's more than just 'decent' in my book. And imagine what your municipality would say if you told them they could offset the costs of fuel and wastewater treatment at the same time - ka-ching!
Taking advantage of existing feedstock (read: waste) beats growing feedstock for most efficiencies. And if you want to look for more viable biodiesel feedstocks, there's a wide number - rapeseed, mustard, jatropha, and palm oil. See the table at Wikipedia. Note that algae wins hands down over crops.