Solar power is an eco-friendly energy source that is obtained from solar power plants. These plants are a collection of solar panels and batteries that absorb sunlight and convert it into electricity. Solar technology is still being perfected, but it has come a long way. At the moment, there are two types of common solar power plant setups. There are photo-voltaic power plants and there are thermal power plants. Both types of plants harvest energy from sunlight in a different manner.
Today, we’re going to take a look at each of these power plants and figure out how they work.
Photo-voltaic Power Plants
Photo-voltaic solar technology has the ability to convert sunlight into electricity. It makes use of solar cells that, when exposed to sunlight, produce energy. Solar cells rely on the photoelectric effect in order to produce energy. A solar cell’s structure consists of semiconductor material. When this material is exposed to sunlight, it reacts by releasing electrons.
There are two types of photo-voltaic solar panels out there; crystalline solar panels and thin film solar panels.
Crystalline Solar Panels
These solar panels are made using crystalline silicon. Their structure can be mono-crystalline or multi-crystalline depending on their quality. The former tends to be more efficient. You can expect an efficiency of 15% to 20% from quality crystalline solar panels. Solar panels with multi-crystalline have a lower efficiency (13% to 16%). These efficiency number aren’t set in stone. Solar panels are being improved at a rapid pace. This is leading to higher efficiency and lower production costs.
Thin-Film Solar Panels
Thin-film solar panels have a flexible structure that consists of multiple films. Each film is made of a different material and extracts light at different parts of the EM spectrum. Thin-film solar panels are made using morphous silicon, copper indium, cadmium sulfide, and cadmium telluride.
Their thin and flexible structure makes them ideal for use in different situations. Devices with integrated solar panels are fitted with this type of solar panel. Thin-film solar panels are also being considered for integration with building structures.
Power Production in Photo-voltaic Powerplants
A photo-voltaic powerplant produces electricity and then feeds it into the national grid. In order to do this, they need the following components:
- Solar panels with a DC current generation capability of up to 1500V.
- Power plants that produce more than 500KW require step up generators as well.
- Components for converting DC current into AC current.
- Reliable monitoring systems that keep a close eye on how the power plant is performing.
Whenever a solar panel is exposed to sunlight, it produces electricity by means of the photoelectric effect. This electric is a Direct Current (DC) and needs to be converted into Alternate Current (AC) before it can be used. The conversion is done by inverters.
A great thing about photo-voltaic power plants is that they are self-sufficient. Once they have been setup, they function without the need for any external help.
Thermal Solar Powerplants
This kind of solar powerplant harnesses the sun’s heat energy for producing electricity. They function by concentrating the sun’s heat into one spot. This produces an ample amount of heat. This heat can then be used to create steam. The steam can then be used to move a turbine and produce electricity.
There are three kinds of thermal solar powerplants:
- Parabolic troughs
- Solar power towers
- Solar Ponds
This kind of powerplant makes use of parabola shaped reflectors. These reflectors are capable of amplifying the intensity of sunlight by 30 to 100 times. The result of this amplification is the ability to produce intense heat. This heat can be used to heat-up liquids and produce high pressure steam.
A parabolic trough has self-adjusting mirrors that follow the sun’s movement throughout the day. This allows them to use up the maximum amount of sunlight throughout the day.
Parabolic troughs also use either linear concentrating systems or solar dish systems. Both collect energy at one point and then transfer it from one part of the powerplant to the other. Linear concentrating systems make use of U-shaped mirrors. These mirrors have short focal lengths and large apertures. They can easily increase the intensity of sunlight by up to 30 times.
Solar dish systems use satellite dish like structures with small mirrors in them. The structure has a collector at its focal point at which all the sunlight gets directed. The collector transfers all the heat to engine generators that use it to produce electricity. Compared to linear systems, solar dishes are capable of producing far more heat.
Solar Power Towers
This powerplant makes use of a tower that is covered in heliostats. Heliostats are flat fun-tracking mirrors that concentrate solar energy into the tower. Solar power towers can increase the intensity of sunlight by 1500 times.
Solar power towers produce electricity by heating up air and using it to power turbines. They can produce temperatures as high as 700 degrees Celsius. Liquids can be used in placed of air for the same effects. The better heat retention a solar power tower has, the more efficient its production becomes.
Solar towers have a few advantages over other solutions. They are quite durable and can actually operate during the night. If a solar tower can retain enough heat, it can continue producing electricity even after the sun goes down.
Solar ponds make use of saltwater to trap heat and then use it to produce electricity. They make use of salinity-gradient technology. Solar ponds can retain energy for later use as well.
A solar pond powerplant requires a huge amount of saltwater in order to work. An enormous body of saltwater has different densities at different depths. The deeper you go, the denser the water becomes. The solar pond setup works by gradually absorbing heat from the sun. The sun’s heat gradually penetrates deeper into the pond. Once it reaches water with higher density, it gets trapped more effectively. Depending on the water’s salinity, it can retain temperatures ranging from 30 to 90 degrees Celsius. And this hot water can be used for powering turbines that generate electricity.
After going through our article, you will now have a better understanding of how solar power works. The sun’s rays are packed with energy that is waiting to be harvested. Solar powerplants harvest this energy and convert it into electricity.
Solar technology is undergoing a lot of advancement. It is becoming more efficient and more affordable as well. Thanks to this, we can see it being adopted throughout the world. Given time, solar technology will become our primary method for energy production.