Sweden has a climate target to get a total renewable electricity production by 2040, in order to succeed with the goal, the proportion of solar energy needs to increase. Increased environmental awareness and increased profitability of solar cells have led to an increase. A new way of attaching solar cells to buildings is by integrating them into building materials. A solution that optimizes material, makes the installation easier and creates better design. Today, there is concern that the temperature of the solar cells may become very high as their cooling decreases. The consequences of an increased temperature in the solar cells is that the efficiency of the electricity production decreases. The purpose of this study is therefore to increase understanding of the influence of modular temperature on electricity production. The aim of the study was to find out how much electricity production [kWh/m2, year] varies in solar cells depending on whether they are applied to buildings or if they are integrated into building materials for solar cells placed in Nordic climate. In order to do this, a calculation model was built in Simulink Matlab to calculate how the modular temperature varied during the varying weather conditions that occur during a year in Gothenburg. Air flow in the gap is created by self-convection. Some periods blew the wind into the gap in the ceiling and then the wind was also assumed to contribute with an air flow. In order to describe the self-conception, a theoretical relationship was established, to describe how the wind influenced the airflow of the roof, a connection from an experimental study was used. With the help of the calculated calculation model, it was possible to determine how much electricity production varied during integrated or applied assembly in Gothenburg. The result found was an increase of 4% for ceiling-mounted and 2% respectively for wall-mounted solar cells with applied mounting compared to integrated installation. The model was also tested for a warmer and a colder climate, Rome and Luleå. The conclusion was that building-applied solar cells can increase electricity production by up to 4% for solar cells on roofs and up to 2% for solar cells placed on the wall in Nordic climate compared to fully integrated solar cells, an air gap is therefore more effective for solar cells placed on roofs than on the wall. It was found that in warmer climates, as in Rome, the corresponding increase in electricity production was about double that for both roof and wall, an air gap is therefore more efficient in a warmer climate.