Solar energy is energy generated by our sun in the form of solar radiation, and this solar radiation can be used to generate electricity. To accomplish this conversion, it is necessary to use photovoltaic cells, which are made from materials that exhibit the ‘photovoltaic effect’. The photovoltaic effect occurs when the sun’s radiant energy strikes the cells, and photons excite the cell’s electrons into movement and cause them to flow, thus generating an electrical current.
Clean and renewable
Solar energy is the cleanest and most abundant source of energy available on our planet, and the fact that it’s a renewable energy source gives it a decided advantage over some of the more traditional forms of energy like fossil fuels, which are not renewable. Modern technology is capable of harnessing the power of the sun to provide the electrical needs of residences and businesses, and continuing research into solar energy generation is expected to make great advances in the future.
Soon there will be far greater numbers of users serviced and supplied with solar energy as ways are found to refine and increase the effectiveness of the technology. At present, because the sun is not always shining, for instance at night or on cloudy days, radiant energy from sun is not always available for conversion into electricity.
This makes it necessary to store the energy collected from the sun in some type of battery, so that a relatively constant supply of energy is available for residential or commercial use. In practice, when the demand for electricity is greater than a battery’s capacity for energy storage, it is sometimes necessary to provide a backup source of energy, such as a tie-in to the local utility.
Other methods of conversion
In addition to photovoltaic generation of electricity, solar energy from the sun can be converted into electricity by several other methods, such as solar heating and cooling, concentrating solar power, and passive solar energy generation. Passive solar electrical generation is the only one of these processes which does not use a mechanical or electrical device to convert the sun’s radiant energy into electricity. Passive solar cells are designed to collect and store sunlight without the use of any moving parts like collection panels.
Solar energy is characterized as a flexible energy technology, in that power plants can be set up to generate solar energy very near the point of usage, which is called distributed generation, or as a utility-scale solar power plant, which is very similar to traditional power plants.