According to the WorldWatch Institute’s September 2006 report on American energy, the Southwestern U.S., if its solar alternative energy capacity were adequately developed, could provide ten times–seven million megawatts–the amount of energy currently being produced from all U.S. energy sources combined.

And the alternative energy solar plants would be constructed on land that has little commercial or agricultural potential, yet is situated close to several major cities.

The National Renewable Energy Laboratory has estimated that a single ten square-mile solar power plant could produce as much alternative energy power as the hydroelectric power provided by the Hoover Dam.

Desert-based alternative energy solar plants collect and concentrate sunlight to create heat for powering industry, or for conversion into electricity.

And that electricity generation will be at its peak during the summer air-conditioning season, exactly when the demand for it is greatest.

There are currently four methods for concentrating sunlight to produce alternative energy.

Tower systems have an array of large mirrors focusing the sun to heat the fluid in a central tower. The fluid produces steam to drive a turbine, generating alternative energy electricity.

Trough solar technology acts on the same principle as tower technology; rows of large mirrors heat the fluid in a trough, producing steam to power a turbine.

Both trough and tower alternative energy solar systems can also store heat in molten salt, releasing it as additional steam power when needed.

Creating alternative solar energy with dish mirrors, like TV dishes, parabolic solar dish systems concentrate the sunlight onto a receiver, which heats to power a thermal engine.

Finally, there is the photovoltaic–PV–system, producing alternative energy with either moving mirrors or lenses, which track the sun and focus the sunlight on silicon cells.

Trough technology has provided alternative energy power in California’s Mojave Desert since the 1980’s, proving the most reliable and economical of all solar power options.

If the construction costs of alternative energy solar plants can be decreased with more efficient assembly and technology improvements, alternative energy from the Southwestern sun could go a long way to keeping all of America warm.