In five years’ time you could be filling up your car with algae – or at least biodiesel made from the sticky green stuff, writes Guy Bird

Would you Adam and Eve it? With current biofuels on the environmental ropes due to serious questions about long-term sustainability, real eco benefits and diversity-robbing problems, eco fuel types and politicians have been desperately scrabbling around for alternatives – and the latest dream ticket could be.algae.

Yes that’s right, the pond life rootless plant stuff you might remember poking around with a stick when you were about six while looking for frogs down the woods. (or was that just me?).

Anyway, algae apparently work as a good fuel source. Requiring only sunlight, water and carbon dioxide to grow they can quadruple in biomass in just one day. And while they’re growing they absorb harmful pollutants including nitrogen and CO2. They’re oil-rich too, some variants containing as much as 50%.

Compared to other raw materials used to make biodiesel, algae are much more prolific. An average acre of algae – already grown commercially for the pharmaceutical industries – can yield 19,000 litres of biodiesel while an acre of corn only makes 1600 litres and an acre of soya beans musters a measly 265 litres.

Douglas Henston, CEO of Solix Biofuels, an algae-growing expert for biofuels, reckons replacing all current US diesel fuel use with algae biodiesel would require using only about 0.5% of the farmland in production today. Algae can also grow on marginal lands, like desert areas where the groundwater is saline.

&#8220An average acre of algae, already grown commercially for the pharmaceutical industries, can yield 19,000 litres of biodiesel while an acre of corn only makes 1600 litres and an acre of soya beans musters a measly 265 litres.”

Guy Bird

As always with these seemingly all-conquering new eco solutions, there are a few caveats. The tricky bit is creating an environment where the algae can avoid contamination by other species and get the right levels of temperature, light and salinity levels. Enclosed systems with multiple layers of tubes in shallow ponds is one man-made option, but such photobioreactors are very expensive so far.

According to a recent Worldwatch report on biofuels, in the short term, algae production for fuel is only likely to be economical in cases where the organisms are grown near power plants, where they can also help soak up the pollution. Another US company, GreenFuel Technologies, is building such systems in Arizona, Louisiana, and Germany, and hopes to capture as much as 80% of the CO2 emitted from the plants during daylight hours.

The car industry is already sniffing round the idea. Indeed the winning LA Show design challenge competition entry last year was a see-through eco Hummer 02 concept that envisaged the same idea on the move. Powered by a fuel cell (what else?) it featured a revolutionary phototropic body shell able to “breathe” via algae-filled body panels that transform harmful CO2 into pure oxygen and then subsequently release it back into the environment. It’s no more than a CAD drawing design study for now, and according to the GM design project chief it could have a few odour issues because algae – you’ll remember from your pond excursions – can pong a bit. But given GM’s plug-in hybrid antics and recent green awakening more could come of the project.

Either way, a car breathing oxygen on-board won’t be a pre-requisite of using biodiesel produced from algae in the future. Normal cars will be able to fill up with the stuff too. If they can make it cheaply and sustainably enough, maybe then Alistair Darling will give algae biodiesel a tax break, if not the current types. I can almost hear the chants now: “What do we want? Duty rebates for pond life! When do it want it, when/if they can make it sustainably!” Catchy huh?