Biofuels

A blog post at The Freeman looks at algae as an energy source. How Dense Can They Get?

The subtitle for this piece: "Good fuels need no subsidies."

Industry is more than willing to risk research dollars on technologies that show real promise, but it is not willing to flush shareholder money down a rat hole. Politicians, however, operate from different incentives. When a crisis, real or imagined, makes headlines, they want voters to see them doing “something” about it, and they must move quickly because election cycles and constituent attention spans are short. Funding long-term research in promising technologies is not sufficient to meet politicians’ needs. Solar panels, wind turbines, and ethanol refineries are all current technology and can be erected quickly with fanfare and photo-ops. By the time these alternative power sources prove to be financial and, possibly, environmental busts, the politicians will have been reelected and voters’ attention will have shifted to the next crisis.
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Biofuels are carbon-neutral because the carbon dioxide released when they are burned is first extracted from the atmosphere by the algae. Unlike burning petroleum-based fuels, then, burning biofuels will not result in a net increase in atmospheric CO₂ levels.

With algae’s vast potential, it is easy to understand why private industry is interested and why no government subsidies are needed to encourage investment. Moreover, if algae-based fuels do not prove viable, the companies now researching them will have no “status quo” problems with ending their investments and shifting scarce resources to more promising technologies – where “promise” is measured in density.

And it may be possible to boost algae's productivity to 100,000 gallons per acre per year.

Gibson Consulting estimates the world uses 1000 barrels of oil per year. That's 42,000 gallons per second. At 31.56 megaseconds per year, that's 1.33 trillion gallons per year. It would take 13.3 million acres of algae farms to make that much fuel. At that rate, plot of land 145 miles on a side would supply the world's energy needs.