Solar+Power

http://www.wired.com/design/2014/03/moss-solar-panels-power-pocket-radio/

Solar Cell Basics If 0.5% of the sunlight falling on to the United States and turn it into electricity we would meet our current energy demands. The reason no one suggests doing this rather than building wind, nuclear or conventional power stations is the cost. We currently use silicon solar cells to turn sunlight into electricity but they are expensive and require subsidies.

Silicon is a poor conductor of electricity because all of its four outer electrons are bound up in the chemical bonds holding the crystal together. However, by adding a tiny amount of phosphorous, which has five outer electrons, you effectively add a free electron to the crystal and make it conduct moderately well. Similarly, you can add boron, which has only three outer electrons, and effectively do the same thing, only now the conducting charge is called an electron hole.

The magic comes when you put a phosphorous silicon layer next to a boron silicon layer: the holes and the electrons cancel each other out at the junction but create an electric field that means that electrons only like to flow in one direction across the junction. This is called a diode.

There are many flavours of diodes, each having a different junction architecture. Light-emitting diodes (LEDs) emit light when electrons flow across the junction but the opposite effect also works: light hitting the diode creates an electric current, and this is how a solar cell works.

http://www.theguardian.com/technology/2014/mar/02/perovskite-lightbulb-moment-abundant-solar-power-britain

DIY solar Cell http://www.ehow.com/how_7276078_make-homemade-photovoltaic-solar-cell.html