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Breakthrough in Capturing Lost Energy in Solar Cells

"Hot carrier" solar cells could be twice as efficient as today's

2 min read

18 June 2010—Material chemists at the University of Texas at Austin and the University of Minnesota say that according to their research, the efficiency of a solar cell may potentially be increased to more than 60 percent, up from what was thought to be a limit of about 30 percent. They report their findings in today’s edition of the journal Science.

From a cost standpoint, boosting efficiency is one of the keys to making electricity from solar cells competitive with fossil-fuel-derived power. “Imagine the practical applications” of a solar cell more than twice as efficient as today’s, says Xiaoyang Zhu, a chemist at the University of Texas. The work he and his colleagues have done, Zhu says, proves that formerly squandered energy “can be taken out and worked with.”

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This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

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