PV Solar panels, basic terminology:
Among all the data and specifications about pv panels that can be found in the current solar market, the most important ones that we must know for a correct calculation of any pv installation are:
- Short-circuit current (ISC): value of the current that flows when the voltage at the terminals of the plate is zero, V = 0 volts. In addition to this, it is the maximum current that could be obtained (in an ideal case) from the solar panel when it works as a generator.
- Open Circuit Voltage (VOC): The highest voltage that can be obtained from the solar module when it works as a generator.
- Maximum power point (PM): point of work in which the power generated by the solar pv module to the external load, is maximum.
- Fill Factor: The ratio between the maximum power (or output of the current and voltage at the point of maximum power) and the ISC and VOC product. Its value is higher the better the cell.
- Efficiency: relation between the electrical power delivered by the solar panel and the power of the radiation that affects it.
The solar modules generates electricity as a function of the incident radiation. The greater solar radiation, the greater the production. We can appreciate it in the following graph: It can be seen over, as a function of incoming solar radiation (measured in W / m2) the solar panel generates more or less current, the voltage being almost constant, for that reason, to greater current and, consequently, higher radiation power. It is true that temperature also plays an important role, because for each degree centigrade that exceed 25 ° C on the surface of the panel, production is reduced by about 0.4%. Therefore, the ideal situation is always low temperatures and sun.
Types of solar panels:
Finally we can not forget to mention which are the types of solar modules that are commercialized today. Basically we should talk about monocrystalline and polycrystalline solar panels, since they cover almost 90% of the current market. As basic information about these two types of modules, we can say:
- Monocrystalline solar panels are formed by monocrystalline cells, which are the type of cell that can be distinguished by its “black” color and with the corners cut with a chamfer (result of the cell cut).
- Polycrystalline pv panels are composed of polycrystalline cells that we can differentiate by their “blue” color and do not have that chamfer in the corners like the monocrystalline ones, but they are perfectly square.
Monocrystalline is always more efficient than polycrystalline, but also its price is always little higher. Choose between one or another type of technology is always always depending on the type of project, the investment that wants to be made … etc.
If you need an offer or know our pv panels cost for your pv system, or also our technical support, do not hesitate to contact us. We will advise you with the best option for your project and we will send you our best proposal without any compromise.