Introduction

Every day, the Sun provides us with several times as much energy as we use. With the Sun is overhead, a single acre of land receives about four thousand horsepower from the Sun. In under three days, the energy reaching the Earth from the Sun is equivalent to more than the total fossil fuel reserves on Earth!

So why don't we use all this energy? The answer is that we do, and have been doing so since life began. Virtually all the energy on Earth ultimately comes from the Sun, and we use it in a huge variety of ways, from using sunlight to grow crops to burning coal in power stations (whose energy initially came from sunlight).

Image taken from www.cs.princeton.edu without permission

A large part of our current energy comes from fossil fuels. These were created from deposits of dead organic matter which have built up over millions of years. However, we are currently using fossil fuels at a rate much greater than they are created. Within a few hundred years, most of the fossil fuel deposits on Earth will have run out and we are faced with a potential energy crisis. This has led to a large interest in renewable sources of energy, such as wind, tidal and solar energy.

There are many different ways in which we can directly harness the Sun's energy, ranging from the very simple such as south facing windows to the more complex, such as photovoltaic cells. The focus of this website will be to look at photovoltaic cells.