The quality of photovoltaic panels determines the power and lifetime of the entire installation. The most efficient PV panels – monocrystalline – also have the best electrical parameters, as well as high durability. Polycrystalline panels are less efficient, and amorphous ones are the least efficient.
Regardless of which panels you choose, you always have to pay attention to the quality of the components. Before you buy photovoltaic panels , check whether the quality is adequate to the price and whether all technical parameters indicate good quality of the equipment.
The selection of a specific model should be determined by such criteria as:
- parameters (the most important – they can be found on the catalog card) power
If we are not specialists, checking photovoltaic panels can be difficult for us. That is why it is worth buying from a manufacturer or distributor that offers equipment with a good reputation and can give us the technical sheet of the panels and explain everything we do not know about.
Let’s pay attention to whether the photovoltaic cells selected by us meet legal requirements, all guidelines applicable in the country, regulations and technical standards, and whether they have been tested in this respect by independent certification bodies. How m
Information from the technical sheet
The catalog card contains a lot of detailed data, which may not tell us anything. Specialists pay attention to pick out at least the following from the multitude of information, symbols and markings:
- Power at MPP (PMPP) [W] STC – the parameter specifies the power at the maximum operating point for standardized test conditions and is a reference point for. planning / designing a PV generator.
- Power at MPP point (PMPP) [W] NIGHT – the parameter will help us determine the power of the panel in conditions closer to reality, that is in normal operating conditions.
- Temperature power factor PMPP [% / K] – this is one of the most important parameters indicating what power the panel will be at a given temperature. It tells you by how many percent the panel power will decrease with each degree above the test temperature of 25 degrees C
- Efficiency [%] – the higher the index, the better.
- Cell temperature at rated operation – this parameter determines the tendency of the module to heat up during operation under normal operating conditions. A good quality panel should have a parameter of 45 degrees C or less
- Linear warranty – the parameter indicates the minimum power of the module guaranteed by the manufacturer over the years of using the installation – the higher the values, the better.
If we are still not sure whether the selected panels are of good quality, let us ask an advisor for help.
Another important issue is the warranty period. From the point of view of the user of the photovoltaic installation, it is important that the warranty will only apply when the panel is installed in accordance with the installation instructions applicable to him. A good company selling and assembling photovoltaic panels uses only certified assembly structures and gives a guarantee for the work it does.
Buying photovoltaic panels from a legal source, from a reliable distributor, is a matter of quality, safety and warranty.
Under no circumstances should we buy photovoltaic panels at suspiciously low prices. High- quality photovoltaic panels are certified to carry out tests of mechanical and thermal strength, as well as resistance to the effects of certain chemical factors. Low-quality panels do not have such certificates. A low price may also indicate that we are dealing with a used panel that has been “refreshed” by a dishonest company and offered for sale again as a full-fledged new product.
What are the most common disadvantages of low quality PV panels
- Broken cells – this defect can be seen with the naked eye, it is also visible when trying the electroluminescence test.
- Scratches and cracks on the glass during inadequate transport conditions or still at the production stage; damage to the glass coating may cause air, water and dust to enter the interior of the panel, which will result in delamination (delamination of the anti-reflective coating).
- Dirt inside the solar panel. They could have got there through cracks formed during transport, but if the glass coating is not cracked, it may mean that they got inside the panel during the production process – for the customer it is a clear signal that the PV panel production process was not very precise and does not guarantee proper maintenance. product quality and durability.
- Poor quality of cables and connectors – the use of unsuitable materials may weaken the electrical connection in the connectors, the so-called connectors, and consequently to destroy the connector. All materials used for the production of PV panels, wiring insulation and electrical connectors must be resistant to low and high external temperatures, resistant to moisture and freezing, and must not be subject to the harmful effects of UV radiation.