How to choose solar PV modules (solar panels)?

The solar module is the most important and at the same time the most expensive component in any photovoltaic system (solar power plant). The successful and long-term profitable operation of the solar PV station largely depends on its reliability, durability and efficiency. Given the large representation of manufacturers, choosing the type of solar panel is not an easy task, it requires maximum care. Let’s highlight several parameters that are most important when choosing a photovoltaic module:

• Getting a brand rankings Tier-1 (or Tier-2).
• The existence of quality insurance from an independent insurance company.
• The presence of international certificates UL or IEC.
• The protection of PID degradation.
• The possibility of receiving the flash report on the initial control for each solar panel you purchased from binding to its serial number.
• The admission of buyer’s representative to the producer’s plant during the initial control and packaging party solar modules.
• A number of other technical and commercial factors.

For five years after substantial solar batteries price decline (up to 2,5-3 times)  geographical spread of manufacturing has also changed. With no doubt China nowadays is the  leader in photoelectric modules production. Thin-film (flexible) panels take only 6% of the market, and 88% of produced samples have Chinese origin (being manufactured directly in China or made from Chinese components). Policy of photoelectric industry subsidizing and support, to which Chinese government adheres very strictly, allows to raise quality standards for manufactured solar batteries together with substantial producing costs decline.

Avenston monitors prices and terms on photoelectric modules market for many years, so our experience will help to pick up the optimal equipment on the basis of object’s purpose, its operational specifications, maintenance conditions and project budget. We offer the best quality solar panels at reasonable prices.

Monocrystalline or polycrystalline solar modules

The modern market of solar modules mainly offers products of three main types: silicon (single-crystal mono-Si and multicrystalline poly-Si) and thin-film. Last type is not very popular for electricity production at industrial scales (despite the fact that the thin film has some advantages, its productivity is considerable lower compared to silicon-based modules). So, a choice of solar panels is actually the choice between two most popular technologies of their production: monocrystalline or polycrystalline silicon.

It is commonly believed that mono-Si solar modules have several advantages over their polycrystalline (multicrystalline) counterparts, but also differ in cost:

• Solar monocrystalline silicon modules have greater productivity and efficiency in the generation of electricity than polycrystalline.
• Mono-Si panels usually have higher reliability and durability.
• For the installation of solar power plants in conditions of space shortage (for example, on the roof), highly efficient single-crystal panels are best suited, as their installation allows you to save the space occupied by the solar station.
• The cost of mono-Si panels (monocrystalline) is slightly higher than that of poly-Si (polycrystalline) solar panels.

The last fact, perhaps the most certain, is that the price of mono-Si modules is really higher than their counterparts, but made using polycrystalline technology. But it is much more important to know which particular panels – monocrystalline or polycrystalline – have a better price / performance ratio. In addition, it is important to consider how much space you can save if you replace poly-Si panels with mono-Si in the design documentation.

In order to thoroughly understand which of the above facts correspond to reality, and which are simply marketing strategy of equipment manufacturers, our engineers periodically conduct their own research on this issue, drawing on the practical experience of already implemented projects, the mathematical models developed by us, and also use specialized software systems. To determine the relative efficiency of solar panels of different types and different manufacturers,  it is usually used photoelectric modules of the same power and belonging to the same series on the analysis. Our studies were carried out on the basis of a mathematical model of a 10 MW photovoltaic solar station built in the central regions of Ukraine (average insolation in the country). Analysis of all photovoltaic modules was carried out under the same conditions: a fixed angle of inclination of the panels to the earth’s surface and the same type of network inverters. Comparison and modeling was carried out on the basis of solar panels from manufacturers included in the TOP-20 of the world classification. The results of the study were confirmed by calculations using specialized software. The gained data were generalized and analyzed, which allowed us to conclude that the prevailing opinion about the significant advantage of single-crystal modules over polycrystalline is not always true.

Different manufacturers compare different types of solar modules with different results. For example, a manufacturer like JA Solar has a 2% higher efficiency index for mono-Si panels than polycrystalline ones. But at the same time, the results of comparing the panels made by another company gave the exact opposite result – poly-Si panels turned out to be even more productive than their single-crystal equivalents. It should be noted that the periodic repetition of this study for several years with more productive and modern panels does not always confirm the results described above. Photovoltaic technologies are improving, and even for one manufacturer with the transition to a more advanced technological line, the difference between poly- and monosilicon products may be completely different.

On average, the performance and efficiency indicators of polycrystalline and single crystal of the same power have a slight difference. However, from the point of view of reliability, single-crystal panels have a clear advantage over polycrystalline analogues. In addition, using mono-Si technology it is possible to obtain greater efficiency per unit area. In general, on the market, the price of single crystal panels is higher than that of polycrystalline modules. Therefore, when choosing the type of solar panels, it is always necessary to compare the compliance of the module efficiency and its price, as well as compare with analogues. If the price difference is not too large, then it is worth choosing single crystal panels. Otherwise – no need to overpay and you can use polycrystalline panels for a solar power station.

To make an accurate calculation for your project and your chosen type of solar panels (modules) – contact Avenston. Our engineers will quickly and accurately carry out pre-project modeling of various sets of equipment and suggest the most rational solution for your needs. We will help you to choose the equipment based on the maximum price/quality ratio, the purpose of the PV power plant, as well as your budget.