Scientists at MIT, Tel Aviv University and the US National Renewable Energy Laboratory say they've found a way to use algae to make four times as much fuel as before.
Many types of algae and cyanobacteria can use sunlight to plit water and create hydrogen; but they're reluctant to do so, preferring instead to produce sugar for their own needs. However, the MIT team says it's found a way to use bioengineered proteins to flip this preference, allowing more hydrogen to be produced.
A multitasking enzyme, introduced into the liquid where the algae are at work, both suppresses the sugar production and redirects the organisms’ energies into hydrogen production. It increases the rate of algal hydrogen production by about 400 percent. The team can't take it any further, they say, as the algae needs to produce some sugar in order to survive.
"It’s one step closer to an industrial process," says Shuguang Zhang, associate director of MIT’s Center for Biomedical Engineering.
Ultimately, says the team, such a system could be used to produce hydrogen on a large scale using water and sunlight. The hydrogen could be used directly to generate electricity in a fuel cell or to power a vehicle, or could be combined with carbon dioxide to make methane or other fuels in a renewable, carbon-neutral way.
The approach, they say, is simple enough that it has promise in developing countries, as well as the industrialized world.