Biofuels

Is Algenol a possible solution to the global biofuel needs?

Paul Woods, CEO of biofuels start-up Algenol, says his system can yield 6,000 gallons (22,700 L) of ethanol per acre annually, compared to 370 gallons (1,400 L) per acre for corn ethanol.

The U.S. corn-ethanol industry, which had grown fat on government subsidies, crashed last year. Perhaps worse, a series of influential studies argued that, far from being a green alternative, corn ethanol drives food-price inflation and produces higher levels of greenhouse-gas emissions than gasoline, because biofuel subsidies encourage forest-clearing.

"If anything, traditional biofuels like ethanol and biodiesel are moving us in the wrong direction," says Nathanael Greene, an analyst at the U.S.'s Natural Resources Defense Council (NRDC).

Promising technologies like electric vehicles remain years away from reaching critical mass, and would require vast changes to transportation infrastructure in the form of recharging stations and cleaner electricity.

Fortunately, firms in the U.S. and Europe are exploring alternatives to food-crop biofuels, using everything from switchgrass to algae. Each technology has drawbacks, and none is fully ready, but in a warming world of finite oil supplies, there is little choice but to pursue them.

There could be a cheap, abundant alternative, one that has none of the inherent drawbacks of agricultural feed stocks: something known as pond scum. Unlike even cellulosic ethanol, which requires farmland of some sort, garden-variety algae can be grown anywhere it is warm and sunny, and it can thrive in saline water rather than precious fresh water.

Not only that, algae eats carbon; a lot of it. So algae-growing facilities could, theoretically, do double duty, as the source of a renewable biofuel and as a significant answer to the question of where to sequester the carbon emitted by fossil-fuel plants.

Most algae firms harvest the organisms and squeeze them to extract oil which was then processed into a fuel, but Algenol's strains essentially sweat oil in a gaseous form that can be condensed into a liquid.

Algenol is poised to break ground on a commercial-scale facility in the Sonoran desert of northern Mexico. The plant's seaside location enables the company to use seawater to grow the algae, and a nearby coal plant could provide concentrated CO2 to turbocharge production.

Not everyone is convinced that either algae or Algenol is ready for prime time. "I would say the hype is well ahead of the reality," says John Benemann, an expert in algae biofuels, who notes that no commercial method yet exists to capture CO2 from power plants and to deliver it to algae facilities.

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