Solar Power Cells, Hot Water, Energy, Collectors

Two for one: Quantum dot solar cells boost power

01.01.70

Scientists designing the next generation of solar cells are trying to do away with waste heat.

Two research groups this week reported advances in a technique to capture a portion of the sunlight's energy that's normally lost as heat. The advances are aiming toward a breakthrough in how much light can be converted to electricity on a solar cell.

In a paper published in Science, researchers at the National Renewable Energy Laboratory (NREL) reported developing tiny crystals a few nanometers in size, called quantum dots, that are able to capture high-energy photons that today's solar cells don't.

Separately, a team from the University of Texas in Austin developed a plastic semiconductor material that was able to double the number of electrons produced from a photon on light. Capturing " hot electrons " normally lost as waste heat promises solar cells that work at 44 percent efficiency, far beyond today's theoretical limit of 31 percent, according to chemist Xiaoyang Zhu at The University of Texas at Austin.

Source: CNET (blog)