How to Colonize an Asteroid
"Solar Power" is the energy pouring in from our local star, the sun. The average suburban house in the United States receives the equivalent of 100 horse power per hour in the form of energy from the sun. There is a lot of regional variation to this power level, but it is this immense influx of energy which powers our weather here on earth. The amount of energy available in space at the distance of our earth from the sun is ten times what it is here on the surface, since much of the energy is filtered by earth's magnetic field and atmosphere. In addition, this energy is available 24 hours a day - not possible here on earth.
To give you an idea of the process of utilizing solar energy, see the solar window box. While this process will not work in space, it can be adapted to do so, and the project is something which you can build from stuff you probably already have out in your garage.
The basic process behind the workings of the solar window box are also those things which make wind and hydro-electric power work. The sun bathes the earth in energy, which in turn drives the winds, and causes water to evaporate from the oceans. The evaporated water (clouds) are blown over land masses by the wind, and the water falls back to earth as rain - filling the rivers which drive the turbines at the hydro plants. Windmills capture the solar energy stored in the wind by using large blades which turn a generator.
None of the above methods of producing electrical power will work very well in space, but there is yet another way to harness solar power - "Photovoltaic Cells" (PV). PV cells generate electricity directly from the sun. While their initial cost is rather high - they generate free electricity with no moving parts - great for use in space. There are more details about PV's in the electronics setion of this spin.