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Solar power is power generated in some way by the energy given off from the sun, which takes the form of heat and light. The sun's energy is the chief supply of power to the entire world's ecosystem, and there could be no life on Earth without it.

How solar energy works

There are many different ways to capture the energy given off by the sun, and people have been thinking up creative ways of doing just that for thousands of years.

Originally, the sun was used for more rudimentary purposes like heating buildings by orienting buildings to face south (a practice still used today), or for growing crops by capturing and transforming sunlight into heat with greenhouses.

In more modern times, many of these ancient techniques have been greatly improved upon, and 21st century technology has opened up whole new avenues of exploiting solar power. Photovoltaic or solar cells are what make up a solar panel, and surprisingly, date back to the year 1880, but still operate on the basic principle of converting sunlight into direct current.

Today, solar cells are made of the same kinds of semiconductor materials, such as silicon, used in the microelectronics industry. For solar cells, a thin semiconductor cover is specially treated to form an electric field, positive on one side and negative on the other. When light energy strikes the solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be captured in the form of an electric current -- that is, electricity.

Since most household appliances work on alternating current, the direct current generated by solar panels must then be converted into alternating current.

The pros and cons of solar energy

The main disadvantage of solar energy is that generating a proper amount of solar power requires at least a minimum level of exposure to the sun. Nowadays, improvement in panels have improved the ability to absorb solar radiation even on cloudy days, but most systems still require a battery and a backup power source to run consistently.

Esthetics is another concern of homeowners who may prefer not to clutter their rooftops with makeshift solar panel setups. However, as integrated solar-ready housing is being built this should not be as much a concern in the future.

The future of solar power

Solar plants that greatly concentrate the sun's energy use giant mirrors (heliostats).
In sunny Spain, the Planta Solar 20 has been in operation since 2009.

Because of the massive untapped potential that exists in solar power, there are many technologies and techniques being developed to generate usable electricity from solar energy.

In a decade or so, installing a solar array for your home could be as easy as using a 'plug-in-play' solar energy system -- connecting into a PV-ready circuit to initiate an automatic detection system that would connect your system with your local utility.

Another "far-out" proposed technology is the use of solar panels in space.

The advantages of such a system would be that the panels would have direct, unfiltered access to the sun's energy for almost 100% of the day. The power would then be beamed to Earth via microwave technology.

It may still only be a theoretical dream, but space solar panels really demonstrate that scientists are thinking big on what comes next in the development of a huge, but yet largely untapped, energy source for the future.

More information on solar energy power around the Web:

Solar energy - Here's an extensive overview from Wikipedia with a history of solar power development and modern applications, its impact on world economics - plus a wealth of photos, related references and resources.

Solar Today - Check out the online edition of the print publication with news, feature stories, blog, Q&A, related information on sustainable transportation, subscription details and contact info.