Cheaper

Traditional solar cells use the same silicon as computer chips. As a result, supply outstrips demand and will continue to do so for the next several years (making it very expensive).

Solar cells can be made cheaper by either using less silicon, or using new materials. Thin films are a way of applying a functional coating to a cheap support material. This could be used to 'spray-coat' the outside of buildings or walls, effectively making building panels into large solar panels.

New solar cells use different materials such as other semi-conductors which are constructed in a solar cell in a similar way to silicon. However, other systems are taking their cue from nature. The Graetzel cell works on a similar principle to photosynthesis in plants. It consists of an organic dye bound to titanium dioxide nanoparticles. The dye absorbs the light and titanium dioxide nanoparticles pass on the electrons. At 10% efficiency, this does not perform as well as silicon. However, it is cheaper and can be applied to a flexible surface.

Graetzel solar cell uses an organic dye and titanium dioxide nanoparticles to capture light and transfer electricity respectively (see Technical University of Delft for further information).