Solar energy captured by solar panels is a limitless form of energy, as the earth is bombarded with extreme amounts of solar energy every day, according to the National Renewable Energy Laboratory. It's also clean, producing no carbon dioxide, and is very low-maintenance, since solar panels have no moving parts.

Unfortunately, the National Renewable Energy Laboratory says its high installation cost makes it up to four times more expensive than the cost of electricity from a standard utility company. For optimal operation and maximum energy production, it requires year-round sunny weather and is very expensive if repair is necessary, according to the U.S. Environmental Protection Agency.