Solar Modules: an Overview

2017.01.25

Explaining all the basics of solar panels; how they work, what different type there are, which are suited for you project, etc.

The idea of converting solar energy into electricity using solar cells has been around since Alexandre Edmond Becquerel found in 1839 that some materials would generate electricity when exposed to light. The first patents for solar cells appeared in the 1950s, and today solar technology has multiplied to include a range of solar cells suited to different applications; there is a photovoltaic module appropriate for any installation site. These different sorts of solar cells vary in cost and their efficiency in capturing solar energy. The main sorts of PV module are thin film, monocrystalline, and polycrystalline. Each has its own pros and cons that make it more suitable in certain situations and less so in others. Each of these solar cells captures solar energy using the same process but they are different in the process used to manufacture them and in the type of silicon used. In the case of thin film panels, they also differ in the type of photovoltaic material used. A brief outline of the advantages and disadvantages of thin film, monocrystalline, and polycrystalline panels will give a good understanding of where each type is suitable.


A Comparison of Thin Film, Monocrystalline, and Polycrystalline Solar Panels

Monocrystalline solar modules are constructed using the Czochralski process. Here, a rod is slowly withdrawn from molten silicon, rotating at the same time. This process creates a cylindrical ingot of just one silicon crystal, which then cools and is cut into thin wafers. This process creates the best-quality silicon and monocrystalline solar panels are generally considered to be the most efficient in capturing solar energy, with efficiency rates of 15-20%. Monocrystalline panels are therefore also the most efficient in terms of space and they also last the longest, with 25-year guarantees common. The main disadvantage of monocrystalline panels is the increased price and the manufacturing process also produces a greater amount of waste silicon as the cylinder is cut into square wafers. The manufacturing process used for polycrystalline modules is quite different. Here, molten silicon is just poured into square molds, allowed to cool, and then sliced into thin wafers. This process is less expensive, produces less waste, and results in cheaper panels. They are not as efficient as monocrystalline panels, at 13-16%, and this means that they require additional space to produce the same amount of electricity. It has been said that the speckled, blue look of polycrystalline panels is also less attractive than other sorts of panel. The third type of solar panel is the thin film type. Thin film solar cells are made by layering PV material onto a supporting substrate material. These panels also use different photovoltaic materials to capture solar energy, such as amorphous silicon (a-Si), copper indium gallium selenide (CIS/CIGS), and cadmium telluride (CdTe). Depending on the type of PV material used, efficiency of these panels ranges between 7-13%. The main advantage of thin film panels is their cost. These panels can also be manufactured to be flexible, which means they could be used on curved surfaces. They work in high temperature areas, cope well in shade, and their uniform look is more subtle. Reduced efficiency rates mean that they require a lot more space and they are not normally suitable for residential sites.


Choosing the Correct Solar Panel

Each sort of solar panel has its own advantages. Monocrystalline panels may be best suited to small domestic roofs, while thin film panels would be better where there is ample space, like unproductive land or very large commercial roofs. Polycrystalline panels represent a good compromise between the other two. Solarodo offers a marketplace to source precisely the correct components for any installation and features panels from all the big suppliers, such as Canadian Solar, First Solar, SFCE, ReneSola, JA Solar, JinkoSolar, Hanwha Q CELLS, Trina Solar, SunPower Corp, and Yingli Green."