Mark Wanlass of the US Department of Energy's National Renewable Energy Laboratory invented an inverted solar cell, and his design was improved on by a team led by John Geisz.

The improved cell provided a 40.8% efficiency in converting light from the sun to electricity; mind you, the sunlight was concentrated 326-to-1.

If the cost of production can be reduced, such high efficiency may lead to solar power plants in desert areas that could produce great deal of power without requiring any fuel other than sunlight.