Crunching the numbers

The rub is bringing cost down, and production up. To do this, scientists must find cheap ways to dry algae and extract the lipids, where energy is stored.

Swiger noted that it would not make sense to spend five dollars of electricity to run a centrifuge to dry out algae, which in turn would only produce one dollar of fuel.

If research goes well, Swiger thinks it will take five years to bring down production costs to $40 per gallon.

But taking even a tiny chunk out of the energy market — ethanol has eked out a 4.0 percent share, for example — can shift the energy mix.

"Four percent is not a lot, and yet everywhere you look there's a pump," Swiger said. "So four percent of a gigantic number is a lot."

Some start-ups are more optimistic. Paul Woods, chief executive of Florida-based Algenol Biofuels, says his company will beat others to market.

He has patented a technology for "sweating" ethanol from algae, without drying it first.

"We see ourselves as a very cheap way to supplement (energy supply)," said Woods, "and the more cheap ethanol we have, the more we're winning in efforts to have independence from foreign fuel."

Woods announced a partnership with Dow Chemical in July to build a demonstration plant, and expects to launch commercial production by 2011.

'No silver bullet'

Experts don't see algal fuel replacing fossil fuels completely, and some have become leery of hype.

The idea of harnessing algae for fuel has been around for decades, they say. Still, no one has been able to make it financially feasible.

"Any fantastic claims will eventually discredit the field if given much credence," said algae expert John Benemann.

Instead, he sees algae as a good source for animal feeds, chemicals and fertilizer.

Back at FIU, Philippidis agreed "there is no silver bullet" to reduce dependency on fossil fuels.

But he saw promise on the horizon, especially as larger companies become involved in algae research. "We are still at an early stage... but as we scale up (production) I think costs will come down very, very quickly," he said.

And if that works, he added, "there is a small Greek island I would like to buy".