Pierre Calleja sees big things in microalgae – microscopic, single-cell plants with the potential to clean the air, propel automobiles and light city streets.

Calleja, a biochemist and founder of Fermentalg, a French industrial biotechnology company that specializes in the production of chemical compounds from microalgae, last year introduced a lighting system for parking garages, city streets and other urban landscapes. The algae street lamps do double duty – providing emissions-free light while scrubbing the air of carbon dioxide.

The bane of backyard pools everywhere may be the key to reducing greenhouse gases blamed for global warming.

Tubes of water swirling with pale green microalgae absorb light through the day, the process of photosynthesis charging the battery of the self-contained unit. The microalgae in the lamp also absorbs up to one ton of CO2 each year. In comparison, a 50-year-old American elm absorbs about 123 pounds of CO2 each year, according to the U. S. Department of Energy's Method for Calculating Carbon Sequestration by Trees in Urban and Suburban Settings.

The lamps would scrub the air where it is dirtiest – in parking garages and along city streets.

A microalgae lamp set up in a parking garage

A microalgae lamp set up in a parking garage. (Photo: shamengo2/YouTube)

“The effects on CO2 would be massive – more powerful than forests,” Calleja says in a video interview.

If they actually work, that is. Some online commentators have raised doubts about the practicality and science of Calleja’s proposal.

But other researchers have been able to generate electricity – albeit tiny amounts – from algae. Stanford scientists developed a nanoelectrode made of gold, specially designed for probing inside cells. They gently pushed it through the algal cell membranes and from the photosynthesizing cells, the electrode collected electrons that had been energized by light and the researchers generated a tiny electrical current.

But don’t expect algae power plants any time soon. The researchers collect amounts of electricity so tiny that they would need a trillion cells photosynthesizing for one hour just to equal the amount of energy stored in an AA battery.

Other projects of Calleja’s are closer to having a practical impact on the environment.

Calleja is tapping into to microalgae for other forms of energy. Fermentalg in December introduced an algae biodiesel that can be run in current European automobiles without restrictions or modifications.

Making biodiesel out of microalgae, Calleja notes, doesn’t distort world food markets by diverting edible grains, such as corn, for use as fuel. The demand for corn to be converted to ethanol has lead to price increases for food in some parts of the world.

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