What is Solar Power Plant

A solar power plant is any type of facility that converts sunlight either directly, like Photovoltaics, or indirectly, like Solar Thermal plants, into electricity. They come in a variety of 'flavors' with each using discretely different techniques to harness the power of the sun. In the following article, we'll take a quick look at the different types of solar power plants that harness the sun's life-giving sunlight to produce electricity.

• Photovoltaics

  Photovoltaic power plants use large areas of photovoltaic cells, known as PV or solar cells, to directly convert sunlight into usable electricity. These cells are usually made from silicon alloys and are the technology most people have become familiar with - chances are you may have one on your roof. The panels themselves come in various forms:
  

  a). Crystalline solar panels - As the name suggests these types of panels are made from crystalline silicon. They can be either monocrystalline or poly- or multi-crystalline. As a rule of thumb monocrystalline versions are more efficient (about 15-20%) but more expensive than their alternatives (tend to be 13-16% efficient) but advancements are closing the gap between them over time.

  b). Thin-film solar panels - These types of panels consist of a series of films that absorb light in different parts of the EM spectrum. They tend to be made from amorphous silicon (aSi), cadmium telluride (CdTe), cadmium sulfide (CdS), and copper indium (gallium) diselenide. This type of panel is ideal for applications as flexible films over existing surfaces or for integration within building materials like roofing tiles. These types of plant generate electricity that is then, usually, directly fed into the national grid.

These types of plant generate electricity that is then, usually, directly fed into the national grid.



These kinds of power plant tend to have the following basic components:-

• Solar panels that convert sunlight into useful electricity. They tend to generate DC current with voltages up to 1500 v;
• These plants need investors to transform the DC into AC.
• They usually have some form of a monitoring system to control and manage the plant and;
• If the plant generates in excess of 500 kW they will usually also employ step-up transformers.
• They are directly connected to an external power grid of some kind.
• Solar Thermal Power Plants

  Solar Thermal power plants, on the other hand, focus or collect sunlight in such a manner as to generate steam to feed a turbine and generate electricity. Solar thermal power plants can also be subdivided into a further three distinct types:
• Solar Power Towers

  Solar power towers are an interesting method in which hundreds to thousands of flat sun-tracking mirrors (heliostats) reflect and concentrate solar energy onto a central tower. This method is able to concentrate sunlight as much as 1,500 times than would normally be possible from direct sunlight alone.

  One interesting example of this kind of power plant can be found in Juelich, North-Rhine Westphalia, Germany. The facility is spread over an area of 18,000 km squared that houses more than 2,000 heliostats that focus sunlight onto a central 60-meter high tower.
• Solar Pond

  Solar pond solar power plants make use of a pool of saltwater that collects and stores solar thermal energy. It uses a technique called salinity-gradient technology. This technique acts as a thermal trap within the pond that can either be used directly or stored for later use. This kind of power plant has been in use in Israel at the Beit HaArava Power Plant since 1984.