Photovoltaic technology is the process allowing the production of renewable electrical energy with the electromagnetic radiation of Sun.
The photovoltaic cell is the basic electronic component using the photoelectric effect of sunlight, several interconnected cells form a photovoltaic module.
Several modules connected in series and/or in parallel form a solar power plant producing electricity for use in islanding systems, or to feed into privat or public electrical distribution network.
Isolated fotovoltaic power plants may directly consume the electricity produced in non grid-connected sites, equipped, with storage device in particolar batteries, in order to benefit of electricity also outside of production hours (p. ex. overnight).
Photovoltaic power plants can also be connected to distribution network, these facilities are equipped with inverters converting the direct current into alternative current, according to the specific characteristics of each local area network (p. ex. 50 Hz frequency). This second installation category requires on purpose no storage device, electricity being consumed by the nearest consumers on the electrical network.
The photovoltaic technology is subdivided into monocrystalline solar modules on one hand, with higher yield and maximum efficency per unit area, for applications on smaller residential surfaces. Polycrystalline solar modules on the other hand have tendentiously the better quality/price ratio, why their use dominates the photovoltaic market with an optimum return and also a predictable lifetime of over 30 years.
The amorphous solar modules have finally considerable potential for the solar industry with various applications and a higher performance by diffused light. However amorphous silicon cells have a lower efficency compared with standard criystalline modules. Therefore they are more suitable for industrial sized photovoltaic power plants and large-scale ground mounted solar parcs, with consequent economies of scale on their production costs and the carbon balance (CO2).
The exponential evolution of the installed total photovoltaic power is in particular the result of technological improvements and especially the massive reduction of production costs considered over the last 10 years, with nearly 250 GW (Gigawatt) newly installed during the year 2022, for total installed power of more than 1 TW (Terrawatt) a capture area worldwide of the equivalent of more than 1’000’000 football fields (5’000’000’000 m2)!