How to choose photovoltaic panels

PHOTOVOLTAIC PANEL COMPOSITION

A photovoltaic panel is an electrical device designed to convert solar energy into DC electrical energy and is composed of several components that form a single unit. The cornerstone of every photovoltaic panel is the solar cell, where this energy conversion takes place.

Another component are buses or busbars on solar cells used to conduct the produced direct current. The entire front side is covered with anti-reflective glass. If we turn the photovoltaic panel to the back side, we can notice the EVA film, it can be either white or transparent in color and is designed to encapsulate the entire panel so that moisture does not penetrate the solar cells.

Another visible part of the back of the panel is the MC4 cables and connectors. Here I would like to draw attention to some manufacturers who use 0.6m cables, this length is only suitable for typical vertical panel installations. Manufacturers thereby save material costs. However, panels with a universal cable length of 1.2m are more suitable, where we no longer care how the photovoltaic panel will be oriented and only these panels can be found in our GBC Solino offer.

Together with the cables, junction boxes and bypass diodes used to bridge the shaded part of the panel are located on the back of the panel. The entire panel is framed by an aluminum frame with a height of 35 or 30 mm.

DISTRIBUTION OF PHOTOVOLTAIC PANELS

Monocrystalline panel, the oldest and most developed photovoltaic panel production technology. It is produced by cutting thin slices (wafers) from a single crystal of silicon. However, this process is very energy-intensive and was temporarily abandoned in the past. At a glance, you can recognize a monocrystalline panel by its black homogeneous cell color. Efficiency is stated above 20%.

In search of a cheaper production technology, a polycrystalline panel was developed, where manufacturers melt many fragments of silicon, for example, scraps from the production of monocrystalline cells, and press them together. The efficiency of these panels is in the range of 15-17%, they are characterized by their bluish inhomogeneous color.

Currently, however, the vast majority of the offered assortment consists of monocrystalline panels, as the volume and optimization of production have been able to reduce these costs to a level comparable to polycrystalline ones.

The next step in the development of monocrystalline panels are the so-called bifacial panels, where the back side of the panel is made of glass, the panel is thus able to convert electrical energy even from reflected light from the substrate below. The increase in efficiency will increase us by 5-30% depending on the conditions. At the same time, the price increase is not too high, approx. 5% compared to a regular monocrystalline panel. However, these panels are not very effective for pitched roof installations where the reflecting surface is too close to the panel.

COLOR OF PHOTOVOLTAIC PANELS

How such a monocrystalline photovoltaic panel will look is determined by the color of the frame and the color of the EVA film, as the color of the cell always remains black for this panel. We have three combinations to choose from:

• silver frame, white EVA film - the most cost-effective, the most efficient - the least heated
• black frame, white EVA film – a price-friendly, effective compromise between the first and last variant
• black frame, black EVA film - so-called full black, beautiful design appearance, higher heating - less efficiency

Now you just have to choose photovoltaic modules from our offer.