Solar Thermal Electric power

Solar thermal systems can also change sunlight into electricity, but not in the same way as PV cells. In most cases, solar thermal systems concentrate (focus) sunlight to produce heat. This heat boils water to make steam. The steam rotates a turbine, which is made of several rows of blades mounted on a large shaft. The steam's pressure flows through the turbine, pushes against the blades, and causes the shaft to turn, much like you can make a pinwheel spin by blowing on it. The turbine is attached to a generator that makes electricity.

Like electricity from PV systems, solar thermal power can be intermittent. To avoid this problem, many systems use a backup system that relies on natural gas to heat the water. Because solar thermal systems concentrate the sun's energy, they need to be located in areas of the world that receive a lot of intense sunshine, such as Hawaii or Mexico.

Renewable Energy Sources
What Is Renewable Energy?
Solar Energy
Photovoltaic Energy
Solar Thermal Electric Power




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