Solar, light and heat radiation from the sun, has been exploited by humans since ancient times using a growing array of technologies than ever before. Solar radiation, along with secondary resources of solar energy such as wind and wave power, water and biomass, make up most of the renewable energy available on Earth. Only a very small fraction of the available solar power is used.
Solar power means generating electricity based on heat and photovoltaic cells. The use of solar energy is limited only by human ingenuity. Partial list of solar applications space heating and cooling through solar architecture, through distillation of drinking water and sterilization, daylight illumination, solar hot water , Solar cooking, and high temperature process heat for industrial purposes. To collect solar energy, the most common way is to use solar panels.
Solar technology is widely described as either passive solar or active solar energy depending on how they capture, convert and distribute solar energy. Active solar engineering involves the use of photovoltaic panels and solar thermal power to harness the power. Passive solar engineering involves orienting a building towards the sun, selecting materials with favorable heat mass or dispersed light property, and designing natural air space.
At present, most of our energy comes from fossil fuels (coal, oil and natural gas). However, reserves are limited. Because demand for electricity is rising rapidly, fossil fuels will be exhausted in a relatively short time. Therefore, people must develop and use alternative energy sources.
An alternative energy source is nuclear power. Nuclear power can provide enough electricity for the needs of the world for hundreds of years, but it can be very dangerous. An alternative source of geothermal energy comes from deep within the earth. Scientists use heat to generate energy. However, this energy is only available in some parts of the world.
Sun, water and wind are alternative sources of energy. Wind rotating the windmill and moving the sailboat. It's a clean source and a lot of energy. Unfortunately, if the wind does not blow, there is no wind energy. As water moves from one place to another, it makes energy. However, people have to build dams to use this energy source. The dams cost a lot of money, so water is expensive too.
The sun releases large amounts of energy each day. This energy can be converted into electricity. Many countries use solar energy for their daily lives. Solar panels on the roof can generate enough energy to heat or cool the entire home. Solar energy is not only abundant and infinite but also clean and safe.
Despite some drawbacks, the potential of alternative energy sources is enormous. However, how to make full use of the energy resources is a question for researchers all over the world.
