Scientists all over the world are working on ways to capture sunlight for human energy use. Some of them are trying to develop better solar cells. Some of them want to imitate photosynthesis, the process plants use to take energy from the sun.

Wim Vermaas doesn’t believe in reinventing the wheel. A group of bacteria found the perfect way to take energy from the sun more than 2 billion years ago. He’s happy to let them continue doing the work.

Vermaas is a professor of life sciences at ASU. He has studied cyanobacteria for the last 20 years. “Cyan” means “blue.” These bacteria got their name from their blue-green color.

Cyanobacteria are some of the oldest living things on Earth. They’ve been around for more than 2 billion years! They were the first plants to use photosynthesis. Without photosynthesis, today’s plants could not survive. We couldn’t survive, either—photosynthesis produces the oxygen we need to breathe.

Vermaas wants to grow cyanobacteria to make fuel for human use. Right now, the bacteria don’t make a very efficient fuel.

“Photosynthesis has more on its mind than making biomass for us humans,” explains Thomas Moore, director of the Photosynthesis Center at ASU. Cyanobacteria are less concerned about making fuel for our cars than about growing and reproducing for themselves.

But genetic engineering lets scientists change their priorities. For instance, Vermaas hopes to grow cyanobacteria that produce high levels of lipids, or fats.

“Lipids are good for biodiesel. We can modify organisms in a way that makes them more productive. You don’t have to rely on Mother Nature’s design,” he says.

Biodiesel is a good option for replacing current fuels, says Vermaas. “You can put biodiesel right into any existing diesel engine. You can transport it using the existing infrastructure,” he says.

Biodiesel releases as much carbon dioxide (CO₂) as regular diesel. But it also gobbles up CO₂ when it is produced. So it doesn’t put extra CO₂ in the atmosphere. As a result, it doesn’t add to global warming.

Scientists are looking at biodiesel and other forms of biofuel as a source of cheap, renewable energy. For example, in the Midwest and in South America, corn is used to produce a fuel called ethanol. But corn might not be the best crop to use for making fuel. After all, if you put the corn in your gas tank, you can’t put it on your dinner plate.

“You can’t use corn twice,” says Vermaas. “If everyone wants to do ethanol, then what are we displacing? Are we reducing the food supply? What are we doing to the soils? In the Midwest, that could be farmland being used to make fuel. In South America, the cornfields were rainforests. It’s not very sustainable. Biofuel isn’t necessarily green.”

The beauty of bacteria is that they can be grown on land that isn’t suitable for anything else. “You can use much degraded lands, as long as they’re sunny and reasonably warm. The water used to grow the bacteria can be reused. You can even take groundwater from agricultural runoff. It contains nitrate which will fertilize the cultures,” says Vermaas.

(first published in 2008)