How Solar Energy Works for Humans

Solar energy is an inexhaustible source of power that produces no harmful emanations like fossil fuels and is more cost-effective than electricity generated by hydro/atomic power plants. This lasting source of natural power was used by people of early civilizations who were familiar with how the solar energy works. As the concern about the future of more conventional power sources grows, scientists are once again turning to solar power for running household and commercial activities. A better understanding of how the solar energy works is being combined with technological innovations in order to arrive at an affordable way of using energy from the sun for supporting life on earth.

Passive and Active Use of Solar Energy

The classic example of human understanding of how the solar energy works can be seen in specially designed buildings that face south (facing north in case of locations in the southern hemisphere). This allows maximum solar light and the associated heat to enter the building while minimizing the same in summer. This kind of intelligence in architecture has come to be known as passive solar design for buildings. A more active use of solar energy is made by creating special kinds of material-called solar heat collectors-for gathering and holding solar energy. These collectors are placed in the open, mostly on the building's roof, to receive solar radiation.

Solar Heating Systems

Specially designed lenses and mirrors are used for concentrating sunrays on a particular point or object so as to heat it up. Concentrated solar rays can produce a temperature as high as 3000 Celsius. Examples of such comparatively simple heating systems include parabolic troughs, parabolic dishes, and central receivers. From a commercial point of view, parabolic troughs have so far been most successful, especially in the American state of California.

Solar Electricity

Modern understanding of how the solar energy works has resulted in the most remarkable technology of photo electricity i.e. electricity produced by light, especially sunlight. The observation of electric current produced in a material by incident sunlight was first reported in 1839 by a French scientist Edmund Becquerel. Photovoltaic cells were invented by scientists at the Bell Laboratories in the 1950s. These cells were made of silicon and could convert a small part of solar radiation directly into electricity when sunlight falls on their surface. Over the decades, these PV cells have been improved both in terms of efficiency and commercial affordability. Now, PV technology is not only used for commercial and scientific projects but also for using solar energy at homes. As the human knowledge of how the solar energy works grows, new means of using solar energy are expected to be worked out for supporting life on earth.