Making the most of it

There are two main kinds of solar energy - solar photovoltaic (PV) and concentrating solar power (CSP). PV directly converts solar energy into electricity using a PV cell made of a semiconductor material, while CSP devices concentrate energy from the sun-s rays to heat a receiver to high temperatures. This heat is transformed first into mechanical energy (by turbines or other engines) and then into electricity - solar thermal electricity (STe). One approach is to develop cells that can convert a greater percentage of the sun's spectrum. around a quarter of the spectrum is made up of infrared radiation, which cannot be converted by standard solar cells. One way to overcome this loss is to use black silicon, a material that absorbs nearly all of the sunlight that hits it, including infrared radiation, and converts it into electricity.