In order to meet the requirements of the Energy Strategy 2050, there is the need for a large-scale energy retrofit of the current building stock combined with the use of solar active systems, in particular BIPV. However, existing tools to assess the potential solar energy yield, such as solar cadasters, present some limits. For instance, they calculate solar irradiation only on rooftops, neglecting hence the potential for façade-applied systems. Moreover, inter-reflections are usually not considered, although their contribution might be significant in dense urban areas. To overcome some of these limits, we present here a simulation-based workflow for the assessment of the BIPV potential in urban areas, applying advanced solar radiation and PV-modeling tools to detailed 3D city models. We use 3D geodata, including buildings with their actual roof shape and overhangs, terrain and vegetation, that are (or will be soon) available for all of Switzerland. In our workflow, all building surfaces are first regularly subdivided according to a given PV module size. For each sub-surface, the POA irradiance is then calculated using weather data from Metonorm and the software CitySim, whose radiation model includes direct, diffuse and reflected components. We finally apply the Sandia cell temperature model and the De Soto “Five Parameter” module model to calculate the DC power of the system. We here show the application of the workflow for some sample buildings in the city of Neuchâtel, while discussing its suitability for urban-scale assessments.