How does Solar work and is it efficient?

Date: 2021 - 12 - 21
Author: Ecolinks


The energy from sunlight can be converted into elecrticty either by using solar photovoltaic cells or by concentrating solar energy to produce heat for electricity generation. Sunlight can interact with certain materials to directly produce electricty in what is called the photovoltaic(PV) effect. The most commonly used material is crystalline-silicon or silicon, but other materials such as cadmium telluride can also be used. To construct a PV cell, PV material is manufactured into ingots and cut into wafers generally 15 cm wide along each side and one-hundredth of a centimeter thick. Wafers are processed into cells, and these are assembled into modules, also called panels. The module usually has 60 to 72 cells mounted on a plastic backing within a frame. The modules are installed in groups called arrays, where the number of modules in each array is dependant on the available space and desired generation capacity of the project.

Solar panel and Li-ion battery generation system for home. Renewable energy concept. Simplified diagram of an off-grid system. Solar panel, battery, charge controller and inverter. Vector.

A Photovoltaic system includes a variety of electronic and structural components and modules to tie the system together, also known as balance of system equipment (BOS). The structural BOS equipment include brackets where the modules are mounted. In the case of ground mounted systems, the brackets can stay fixed or rotate to face the sun during the day. Modules mounted on tracking systems(mounting systems that can rotate) generally tend to generate more electricity than modules on fixed mounts due to the tracking system having the ability to optimize the total amount of sunlight hitting the module throughout the day with its ability to rotate and keep track of the location of the sun. An inverter is a key piece of the BOS equipment and is an electronic device that is used to convert the electricty generated by photovoltaic modules into a usable form. Other BOS equipment include charge controllers, circuit breakers, meters, and a switch gear. Some systems also include an integrated energy storage system such as batteries.

Reference list:

Tiedje, T., Yablonovitch, E., Cody, G. D., & Brooks, B. G. (1984). Limiting efficiency of silicon solar cells. IEEE Transactions on Electron Devices, 31(5), 711–716. doi:10.1109/t-ed.1984.21594