How a Solar Energy System Works
Sunlight contains radiant energy that can be harnessed to produce heat and electricity. There are a number of technologies that can do this.
Solar photovoltaic (PV) systems convert sunlight into electricity by passing it through a semi-conductor surface. Solar thermal systems are less sophisticated and involve directly heating a working fluid, usually water.
Solar cells
Solar cells convert sunlight into electrical energy. They are made of semiconductors that strongly absorb visible radiation and are layered together into a single unit. These units can be arranged in large groups called arrays to function as central electric power stations or placed on rooftops to provide an alternative to traditional electricity sources.
When sunlight hits the cell, it causes the free electrons to break apart, leaving behind holes. The electric field then transports the holes to the p-type layer and the electrons to the n-type layer.
To make this happen, the silicon atoms in a SOLAR ENERGY SYSTEM solar cell are purposely mixed with a few atoms of another material — usually phosphorus. The phosphorus adds one extra electron to each of the silicon atoms, making them have five instead of four. While we typically think of impurities as undesirable, this one is essential to the solar cell’s operation. The additional electrons help fill the holes created by the missing ones, creating a current that can be directed by metallic contacts to a power grid for use.
Solar panels
Solar power is a clean, renewable resource that doesn’t create harmful greenhouse gases. It’s also a great way to save money on electricity bills and reduce dependence on fossil fuels.
The sun constantly releases tiny packets of energy called photons. If we could capture just a fraction of this energy, it would meet all of the world’s energy needs. Solar panels convert this light into usable electricity by using photovoltaic cells. They are usually arranged in an array on a roof or other area with unobstructed sunlight.
Each panel consists of 36 solar cells laminated to glass within an aluminum frame and wired together. There are two types of solar panels: monocrystalline and polycrystalline. Monocrystalline panels use a single pure form of silicon, while polycrystalline panels use multiple silicon fragments that are more cost-effective.
The silicon isn’t a good conductor of electricity on its own, so it’s treated with boron and phosphorus to improve its performance. These additions help create a layer of n-type silicon with an excess of electrons and a layer of p-type silicon with a deficit of electrons.
Solar furnaces
Solar furnaces generate heat by concentrating sunlight on a target area. This heat is then converted to useful energy. These systems are designed to operate at higher temperatures than electric furnaces, and they can avoid the carbon electrodes that cause problems in traditional coal-based industrial furnaces. These systems are currently being researched for a range of applications, from high-value products like fullerenes to commodity products such as cement.
The solar furnaces are used for material heating, metallurgical processes, and for research. They can also be used to produce hydrogen fuel. They are a great source of clean energy and help reduce the use of fossil fuels.
Solar furnaces can be used to provide power and heat for a variety of purposes, from cooking food to operating a Stirling engine. They are also a great way to save money on your utility bills. This is because the sun is a renewable energy resource that can be used to replace traditional fuels, such as oil or gas. Solar furnaces work by focusing sunlight on a target area, such as a crucible. The target area is then heated to a temperature up to 3500°C.
Solar power towers
A solar power tower is a type of solar thermal energy plant that uses mirrors to focus sunlight on a central receiver at the top of a tall tower. The heat from the mirrors is used to heat a working fluid that then turns to steam, which powers a turbine generator to produce electricity. Solar power towers use a large number of flat, sun-tracking mirrors called heliostats to accurately follow the sun’s movement across the sky each day.
Each heliostat has computer controlled sun tracking mechanisms that direct the sun’s rays towards a blackened heat absorbing receiver at the top of the tower. The heat-transfer medium in the receiver can be a variety of liquids and gases including water/steam, molten salts, oil, or air.
The molten salt used in the most recent solar power tower plants is preheated in storage tanks to a high temperature before being pumped through the receiver where it absorbs the concentrated solar radiation. This high-temperature molten salt is then cooled to a liquid state and used as a heat transfer medium.
Solar batteries
Solar batteries are a key component of any residential solar system, whether they operate in self-consumption mode or critical backup mode. When in self-consumption mode, solar batteries charge and discharge on a regular basis (cycles) while providing power to household appliances.
In critical backup mode, solar batteries provide energy after the solar energy system supplier sun goes down or during a grid outage. Both modes increase the reliability of a solar energy system and reduce its dependence on the electric grid.
Like the lithium-ion batteries in your cell phone, laptop, TV remote and other devices, solar battery technology is based on a chemical reaction. When you place a solar panel in direct sunlight, it generates electricity through a semiconductor made of silicon that absorbs the light and knocks electrons loose.
The free electrons then travel through a metal contacts on the top and bottom of the panel, creating an electric current that powers appliances in your home. This DC current is sent to an inverter, which converts it into AC electricity that can be used by your household appliances.