Scientists at Harvard University and IBM are hoping to harness the power of a million idle computers to develop a new, cheaper form of solar power that could revolutionise the green energy world.

Researchers have launched the project using IBM's World Community Grid, which taps into volunteers' computers across the globe to run calculations on a myriad of compounds - potentially shortening a project that could take 22 years to just two years.

Harvard scientists are hoping the project will allow it to discover a combination of organic materials that can be used to manufacture plastic solar cells that are cheaper and more flexible than the silicon-based ones typically used to turn sunlight into electricity.

The technology could be used to coat windows, make backpacks or line blankets to produce electricity from the sun's rays.

Technology to make the plastic cells already exists, but they are not yet efficient enough to be rolled out in commercial products.

"It is not now cost efficient, although the materials are cheap because it's plastic," said Alan Aspuru-Guzik, a chemistry researcher at Harvard University.

The most efficient silicon-based photovoltaic solar cells convert about 20 per cent of the sunlight that strikes them into electricity. For now, the organic cells can turn only about five per cent of the sunlight into power - half the level needed to make the low-cost cells a viable energy source.

The researchers plan to publish results of the work once they have discovered a possible combination of compounds.

IBM developed its World Community Grid to advance research of humanitarian projects, such as fighting cancer, dengue fever and AIDS.