Solar energy is an alternative energy source
that involves harnessing the radiant light energy emitted by the sun and
converting it into electrical current. Making it possible for homes and
businesses to make use of the renewal energy source rather than rely on more
conventional means of generating power.
In a home powered by solar energy, batteries
are now capable or maintaining a power supply that will maintain the operation
of appliances such as stoves, refrigerators, computers and entertainment
devices such as television sets. At the same time, the solar powered home can
also use the stored energy to heat and cool the home or operate a hot water
heater. Some homes today use a hybrid power system that integrates the use of
solar energy along with power supplied by a traditional power grid. While the
home is not completely dependent on solar power, this type of system can
minimize utility bills and provide an excellent backup system in the event that
a section of the local power grid should fail.
Once considered extremely expensive to build
and install, the price for solar energy systems is considerably less than in
the last decades of the 20th century. In addition to being more affordable, the
newer solar energy systems are also much more efficient than previous
generations, which helps them to be more appealing to homeowners and business
owners alike.
The photovoltaic effect is the process by which
electrical current in the form of voltage is created when electromagnetic
radiation is exposed to a certain material. Using solar cells, the photovoltaic
effect occurs when very short wavelengths of sunlight impact the matter and
electrons become excited. The electromagnetic radiation is emitted from the
solar panel and collected by another material. This ejection of electrons
results in the buildup of voltage creating energy that can be stored in a
battery cell for later use. Two electrodes are used to collect the voltage,
which can be transferred into the power grid.
The way the photovoltaic effect is harnessed
using solar cells is very basic. Essentially, photons from the sunlight impact
the solar panel and are absorbed by the material. The negatively charged
electrons within the material are knocked away from the atoms, which then
produces electricity. This situation is controlled by allowing the electrons to
move in only one direction in the panel, causing a reverse action in which
positively charged particles flow in the opposite direction. With both of these
actions occurring, a direct current of electricity can be harnessed from the
electromagnetic reaction.
The photovoltaic effect is essential for a
number of processes in modern life. In addition to energy creation for general
purposes, solar cells are essential to spacecraft used by NASA and other space
agencies. Also, the principles of the technology are utilized in digital
cameras in the form of charge-coupled devices as well as electroscopes that
identify static electricity.
Photovoltaic
energy is produced when sunlight is converted into energy with the use of solar
cells or semiconductors. These semiconducting cells are usually made of silicon
and do not contain any corrosive materials or moving parts. As long as the
solar cells are exposed to light, they will produce photovoltaic energy with a
minimum of maintenance. This energy is also environmentally clean,
quiet, and safe.
The term "photovoltaic" has two
parts: photo, a Greek word meaning light, and voltaic, a reference to
electrical energy innovator Alessandro Volta. In 1839, French physicist Edmond
Becquerel discovered the photovoltaic effect, the production of a volt by use
of a semiconductor. This discovery prompted further experimentation with light
sources and semiconductors, which led to the invention of solar cells that
produce photovoltaic energy.
Even though the power output of a photovoltaic
energy system depends on the overall amount of light exposure, it will still
generate energy on cloudy or overcast days. To store this energy for later
transmission, a variety of storage systems are available to consumers. Most
reliable storage systems use a combination of rechargeable batteries and
energy-storing capacitors, some of which can be designed for AC or DC power.
The amount of power available on cloudy days
and at night in a photovoltaic energy system depends on the energy output of
the photovoltaic modules and the battery arrangement. Adding additional modules
and batteries will increase the available power, but will also increase the
cost of the system. Systems that are well-designed offer the opportunity for
expansion or reduction as energy needs increase or decrease.
Photovoltaic energy is emerging as a viable
solution to energy problems worldwide. Its current uses include power stations,
transportation, rural electricity supplies, and solar roadways. While still a
long way from becoming the world’s major energy source, ongoing research into
photovoltaic energy may bring the promise of hope to the future.
