In order to assess the photovoltaic potential of a building in an urban environment, the creation of a 3D model is necessary. However, there are many different levels of detail (LOD) to model a building. In this report, we compared the three main LODs according to the CityGML standard and evaluated the relative error of solar irradiation between them through four case studies in the city of Neuchâtel (Switzerland). Furthermore, we determined if the impact of an exact modelling of surrounding materials proprieties has an influence on the studied buildings irradiation. The three 3D models are designed with the software Rhinoceros, using the Digital Surface Model (DSM), the Digital Terrain Model (DTM) and on a basis of a visual survey through Google StreetView. Through DIVA-for-Rhino, we assigned materials to our model and run the simulation of solar radiation using a Daysim simulation engine. The results highlighted the overestimation of the PV potential for buildings using LOD1 and LOD2 models considering LOD3 as the ground truth. Using the found relative errors, this method could assess the PV potential at the urban scale more precisely without needing a complex model.