Solar cell breakthrough at IBM Labs

Stephen Withers
Monday, 15 February 2010 09:02

Science - Energy

A new type of solar cell invented by IBM uses readily available materials in a way that increases efficiency while keeping manufacturing costs down.

One of the problems with solar cells is the cost per watt. Technologies that do a relatively good job of converting sunlight to electricity tend to use more expensive materials.

For example, current thin film solar cells give between 9 and 11% efficiency, but are made from copper indium gallium selenide or cadmium telluride, and both materials are on the expensive side.

Using cheaper materials by omitting indium, gallium and cadmium has previously resulted in efficiencies of up to 6.7%. But now IBM researchers have combined copper, tin, zinc, sulphur, and/or selenium to create solar cells with 9.6% efficiency.

Production costs should also be reduced, as the new solar cells do not require expensive vacuum-based manufacturing techniques.

"The quest to develop a solar technology that can compare on a cost per watt basis with the conventional electricity generation, and also offer the ability to deploy at the terawatt level, has become a major challenge that our research is moving us closer to overcoming," said David Mitzi, the team leader at IBM Research.

According to IBM officials, the company has no plans to put the solar cells into production but may partner with other manufacturers.