Printed Electronics Gets More Ambitious
Need for a new approach to solar cells
Silicon photocells are seen in many places but the technology is severely limited. Silicon will never give tightly rollable devices let alone transparent ones or even low cost power generation on flexible substrates. No hope here of strong thermo-photovoltaic effects, where heat generates the electricity when light does not. No hope of generating useful power when the light hits at a narrow angle or is reflected from windows or otherwise polarised. The typical silicon photovoltaic unit is heavy, inflating transport and installation costs and it may break into dangerous shards of glass. Amorphous silicon gives thinner layers but it has stability problems and all the above limitations as well, so, if we want a breakthrough we have to look elsewhere. Above all, there is no chance of either option being printed at high speed, reel to reel on low cost substrates using low temperature processes, where necessary involving very wide areas. Ubiquitous photovoltaics will need to be thin, flexible, environmental and very low in cost. Who knows, the subject is advancing so fast, we may even be facing the prospects of variants that are:
