Two main classes of solar panels are available on the market: monocrystalline and polycrystalline. These types of panels are made of silicon (in the form of crystals) and offer the same performance, which does not prevent them from presenting differences.
The cells of the polycrystalline solar panels are blue and monocrystalline silicon cells are black. This gives them a more uniform appearance to the roof. The crystals are all oriented in the same direction. They are therefore more productive in the presence of direct radiation.
Polycrystalline silicon cells can take on several shades, but they are usually bluish. The crystals are like outward-facing fans, which allow them to capture ambient light more easily. They are often a little cheaper than monocrystalline ones.
The high-performance, flexible solar panels are monocrystalline and have a higher efficiency of 18 percent. They are of monocrystalline type and their yield is 18 percent higher. These units are mainly reserved for roofs with limited area since it is necessary to place less to obtain an equivalent yield. The other side of the coin: they are more expensive.
Solar panels do not necessarily have to be installed on the roof at all times. They can also be fixed or mobile. Placing solar panels on top of a roof is the most common type of installation. The panels are placed a few centimeters from the sloped roof on fixing rails. They are suitable for almost all types of roof covering as long as the slope is at least 20 degrees. As a reminder, for optimal performance, the roof will be oriented to the south and will have a slope equal to 30 degrees.
On flat roofs, flexible solar panels can be placed on rails and inclined between 15 and 35 degrees. Depending on the type of supporting structure, the rails can be weighted or fixed. To allow a good evacuation of rainwater, the flat roof must still have a slope of at least 2 degrees. If your roof is badly oriented, it is possible to install photovoltaic panels on an awning. This solution allows you to still enjoy solar energy and have a covered terrace. The inclination is always 30 degrees and the panels are placed on a metal structure.
There are also solar carports but due to high costs they are often reserved for businesses.
Solar trackers are mobile solar panels. They can automatically change their orientation depending on the position of the sun, such as a sunflower that turns to benefit from the rays, which increases the yield compared to fixed panels.