Electricity yield simulation of complex BIPV systems

Building-integrated photovoltaic systems (BIPV) are able to improve the energy balance of buildings. However, this improvement can be analyzed quantitatively only if the electricity yield generated by the BIPV system is calculated. This PhD thesis presents a simulation program that calculates the electricity yield generated by BIPV systems, including those made of geometrically complex BIPV modules. The simulation is based on a combination of a ray-tracing procedure with the resultant I-V curves of electrically connected PV cells. For the annual electricity yield, multi-core cluster computers are applied to perform the simulation on the basis of 5-minute meteorological data throughout a year. The ray-tracing technique is applied to calculate inhomogeneous irradiation, the consequence of shading or reflections from surrounding objects, and the quantitative relevance of reflections from the ground. The temperatures of the PV cells are calculated by taking the physical principles of heat conduction, heat convection and thermal radiation into account. The cell I-V curves are calculated depending on the temperature and the irradiance. After the virtual interconnection of the PV cells in the simulation, the effect of inverter efficiency and its dependence on the generator voltage are calculated, finally leading to the AC power of the BIPV system. All parts of the simulation are validated by comparison with measurements, and the accuracy of the simulation is quantified with the help of statistical measures. Finally, the simulation program is applied to calculate the electricity yield generated by two BIPV systems.