Crystal clear?

ON THE desk of Chris Case, chief technology officer of Oxford Photovoltaics, there sits a small but heavy vial filled with a canary-yellow liquid. “That’s enough for a kilowatt,” he says. The material in the vial is called methylammonium lead iodide, and enthusiasts such as Dr Case believe it, and materials like it—known collectively as perovskites—could lead to a dramatic increase in the world’s use of power from the sun.

Oxford Photovoltaics is one of many firms, both small and large, that see promise in perovskites. These are compounds that share a crystal structure and are named, collectively, after the mineral that was the first substance found to have this structure. Often, they are semiconductors. This means that, like the most famous semiconductor of all, silicon, they can be used in solar cells.

The first perovskite solar cells were made in 2009. They converted 3.8% of the light falling on them into electricity. Now, the best hoover up around 20%. This rate of conversion is similar to the performance of commercial silicon cells, and researchers are confident they can push it to 25% in the next few years.

Moreover,...

from The Economist: Science and technology http://ift.tt/1IDn0vk