Efficiency boost for solar cells

A new type of semiconductor material could lead to solar cells that convert almost half the light falling on them into electricity.

Conventional solar cells have an efficiency of only around 25 percent because the respond to narrow range of frequencies, wasting much of the light energies. The efficiency has been boosted to around 39 percent by using a mix of semiconductors with different responses.

Now researchers at Lawrence Berkeley National Laboratory have found that by doping a zinc-manganese-tellurium (ZnMnTe) alloy with oxygen atoms they produce a material that responds to low-energy photons – promising solar cells with an efficiency of 45 percent, reports the MIT Technology Review .