So powerful that the less-than-one-one-hundredth-of–one-millionth-of-one-percent–.0000000001–of its power which reaches the Earth every day could, if captured, provide enough alternative energy to permanently eliminate mankind’s need for fossil fuels, it is, of course, the sun.

And since 1973, and the OPEC-engineered oil crisis, it has been the object of significant research on ways to turn its radiation into a useable source of alternative energy.

There are several ways in which that energy has already been harnessed.

Solar–also referred to as photoelectric, or photovoltaic–cells were first developed to provide electricity to space satellites. They operate by absorbing the sun’s light and and converting it into a flow of electricity between two oppositely-charged layers.

Solar, or “PV” cells, power many of the digital accessories–watches and calculators, for instance–prevalent in our lives, and are one of the significant ways in which solar power functions as an alternative energy.

Another solar technology, solar water heating, although limited to warm climates, is an alternative energy method for providing electricity when the sun heats water-filled black pipes in rooftop glass panels. The heated water is then stored in a water tank, reducing the home’s power consumption.

Solar power has also provided the alternative energy for solar furnaces, used in scientific experiments requiring extremely high–up to 33000 Celsius–temperatures. The furnaces are surrounded by mirrors which concentrate the sun’s energy in a very small area.

And in the desert outside Barstow, California, is the Solar Two power station, which, from 1995 to 1999, converted the sun’s energy into steam which ran a generator-driving turbine; the turbine, in turn, produced 10 megawatts of alternative energy based electricity. Like a solar furnace, the power plant was surrounded by 1926 solar energy gathering mirrors.

The development of solar power as a viable alternative energy source is still in its infancy, but if the success of PV cells, solar furnaces, and solar power plants is any indication, man’s attempts to harness this free and nearly infinite energy will continue as long as the sun shines.