Most of the solar modules that are available on the market are based on crystalline silicium as the main component. They are divided into two types: The monocrystalline and the polycrystalline solar modules.
The polycrystalline modules are composed from several different siliciumcrystals - hence the name polycrystalline - while the monocrystalline modules are made from one single crystal.
The difference in performace between the two types are quite small. The monocrystalline modules might produce more power when the sun is at a right angle to the module in clear weather, but in more diffused light - in cloudy weather or with the sun more angled - the difference between the two types become less. This is because the polycrystalline modules has crystals which are angled differently. This way, there are always crystals with an optimum angle - no matter the direction of the light.
In general, it is estimated that polycrystalline modules can convert about 15-16% of the sunlight to energy, corresponding to an efficiency of 158 kWp pr. m2.
The monocrystalline modules reaches about 16-18%, and a production of 164 kWp pr. m2. Among others, the type of inverter, placement of the modules, shadow and so on.
It is our experience that the energy production over a whole year for the two types are basically the same.