Science and Health

Copying The World's Greenest Energy From Nature

We'd like to do what plants do for energy, but we'll need the right materials to make photosynthesis viable on a large scale.

Copying The World's Greenest Energy From Nature
California Institute of Technology

Solar panels are great and all, but what if technology could photosynthesize energy from sunlight like plants do? As renewable energy goes, that's the Holy Grail.

Sunlight is the most plentiful, most reliable energy source we have. The fuels from photosynthesis can pack the same kind of punch as gasoline. And the process can even clean the air, just like real plants.

One method uses a catalyst to split water into hydrogen and oxygen, either on its own or with a power boost from a solar panel that makes the process more efficient. Researchers at Harvard University have improved that technique by applying bacteria that refine the hydrogen into different fuels.

And one of the newest experiments, from researchers in Florida, works even more like natural leaves: Organic molecules pull carbon dioxide out of the air.

These modern lab tests are already more efficient than plants, which usually turn less than 1 percent of their sunlight into usable energy. So why don't we have forests full of fake trees to meet our energy needs?

Lightning against a dark sky

Lightning Makes For A Terrible Renewable Energy Source

Lightning is hot and fast — but it doesn't carry enough energy to be a useful source of renewable power.


Efficient water-splitters need catalysts like platinum, which are expensive. We're finding cheaper materials, but some of them corrode if they're in water too long. There's a balance to strike, and we haven't found a commercially viable one yet.

Another challenge is using the fuels these experiments produce. Most consumer cars don't run on hydrogen, for example, and other fuels we can make from the gas take more processing.

But researchers say creating reliable energy from sunlight is worth the challenge. It could help meet the energy needs of a developing world and help the environment at the same time.