Solar energy is radiant energy from the sun.
It is the primary source of energy for all life forms.
The sun shines, allowing plants to grow for food sources or bio fuel. The sun's heat causes temperature differences, producing winds that can power wind turbines. The sun also causes water to evaporate, making hydropower possible.
The term solar energy is often used to refer to the various ways we can use the sun's energy to produce light, heat and electricity.
How is Solar Energy Produced?
We all know that the sun sends heat and light to our planet. But, how is solar energy made?
The sun is a star primarily made up of hydrogen and helium atoms. In a process called nuclear fusion, four hydrogen atoms combine to form one helium atom.
Some matter is lost during the fusion process.
Lost matter travels outward to the surface of the sun. This radiant energy reaches our planet, providing us with heat and light.
How Does Solar Energy Work?
Think of your car on a sunny day. Sunlight passes through the window and is absorbed by the interior. This newly converted heat energy becomes trapped, making the car warmer than the outside temperature.
Passive Solar Energy
Passive solar homes are carefully constructed to operate as a solar collector. Using no mechanical devices, these homes rely on properly placed windows to draw in sunlight. The sunlight is absorbed by the floors and walls, heating the home.
Active Solar Energy
Active solar energy systems use pumps and other mechanical devices. Solar collectors are used to absorb energy from the sun. The most common type of solar collectors look like black glass boxes and are found on rooftops. Inside these flat boxes are metal plates that absorb the solar radiation and convert it into heat. Either air or liquid is warmed by this heat, making it ready for home use or storage.
How is Solar Energy Stored?
Storing solar heat can be a challenge. Materials such as stone or concrete can be used to absorb and store excess heat. Heat is absorbed during the day and released into the home after dark. Water tanks are commonly used for heat storage in active solar homes. Batteries or a grid system are used to store solar electricity.
How & Where is Solar Energy Used?
Solar energy is being used in a variety of ways all over the planet. California currently has the largest solar power plant in the world. Totaling nine solar thermal plants in the Mojave Desert, these technologies are used to create electricity by heating water into steam.
Two large solar plants using photovoltaic cells were recently built in Europe. These have the capabilities to provide a large amount of power directly to an electrical grid.
Solar energy can be used to cook your meals, heat your home and charge your cell phone. For more information, see our article on Ways to Use Solar Energy.
How Efficient is Solar Energy?
Many factors contribute to the efficiency of solar power. Although there is an abundance of solar energy on our planet, it is spread over a large area. Collecting it can be a daunting task. Variables such as climate, time of day and type of solar cells all must be considered.
Why Aren't More People Using Solar Energy?
There are several other problems with solar energy, including the high cost of solar panels. To learn more about solar energy disadvantages, see our article on Solar Energy Pros and Cons.
Solar energy is being used in a variety of ways all over the planet. California currently has the largest solar power plant in the world. Totaling nine solar thermal plants in the Mojave Desert, these technologies are used to create electricity by heating water into steam.
