To squeeze the most out of solar panels, they

To squeeze the most out of solar panels, they should operate in cool, bright conditions – mountain chains like the Himalayas might make ideal sites for solar farms

Think of solar arrays and you'll probably picture panels under blistering desert heat but we may be able to get more energy from solar panels on snow-capped mountains.

Kotaro Kawajiri at the Massachusetts Institute of Technology mapped solar irradiance across the globe in collaboration with colleagues in Japan. They found that some of the highest levels of sunlight can be found in the Himalayas and the Andes: at altitude, less light is lost to the atmosphere.

There's another reason why high-altitude solar power makes sense. At temperatures of around 40 °C, 13 per cent of the energy solar panels would normally produce is lost to heat. The cold air at high-altitude keeps the panels cool and efficient, says Kawajiri.

Keith Barnham, a photovoltaics researcher at Imperial College London, says cold climates may be the new frontier in solar. "There are a lot of underdeveloped regions and communities living high up in the foothills of the Himalayas that could benefit from solar energy," he says.

Journal reference: Environmental Science and Technology, DOI: 10.1021/es200635x

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