How does a solar PV plant produce electricity?
Solar PV (photovoltaic) power plants enable solar cells to convert sunlight into electric current. Specifically, solar cells are packaged together into a module or panel that releases electrons when hit with rays of photons from sunlight. This release of electrons is harnessed by solar panels to produce a large electric current, which is electricity.
How does the electricity get onto the power grid?
The electricity produced by a PV solar plant is a constant stream of current, or “direct current” (DC). This is similar to the type of current produced by a typical AA battery. Once the power is collected from the solar panels, it is run through inverters that convert the direct current electricity into alternating current (AC) electricity, which is the preferred type because its voltage can be altered making it ideal for long-distance transmission.
Once this is accomplished, the power is then run through transformers to increase the power voltage to match the needs of the distribution or transmission line that connects to the facility. Then the power flows onto the transmission line sending power to businesses and homes.
What is the difference between PV power plants and Concentrated Solar Power?
Concentrated Solar Power (CSP) systems use lenses or mirrors to create a large area of sunlight. In most cases CSP facilities are very large and require steam turbines to convert energy into electrical power. Photovoltaic technology does not require a turbine and allows for smaller scale projects where power is produced closer to where it is consumed.
Why not use concentrating solar?
Concentrating solar power (CSP) plants gain economies of scale by being large – typically hundreds of MWs in size to be viable. This facility size is difficult to place near areas with large populations because the land requirements are substantial. Also, CSP plants are cooled by large quantities of water and require large towers that are often visible by residents and may create reflection issues.
What about thin film technology?
The thin film technology also uses a type of photovoltaic cell, with the major difference being the material used to convert sunlight into electricity. The material used in thin film, while less expensive and still durable, is also less efficient in releasing electrons when hit by sunlight. In order to produce the same amount of electricity with thin film, more panels are needed, and thus more land is required.
How many inverters and/or houses are on a PV facility?
As a rule of thumb, a 20 MW project will have about 20 inverter stations.
Are inverters exposed or can you put housing around them?
The inverters can be either exposed or, if desired, housing can be put around them to cover them up. Even if the inverters are exposed, they look more like metal cabinets ortelephone or cable distribution boxes that are usually seen around most subdivisions, shopping malls and offices in the United States.
How big are the inverters? How big would the housing be?
Inverters can be about 7 to 8 feet tall by about 2 to 3 feet wide and about 6 to 8 feet long. Any housing that could be put around them would be about 10 feet tall by 16 feet wide and about 16 feet long.
Can the inverters be grouped together so there are fewer structures?
The number of inverter enclosing structures would range between four and 10. The size of an inverter enclosing structure would be between 16’x16’ and 24’x24’.