In this paper we introduce a quasi 3-D electrical model for a high efficiency interdigitated back contact (IBC) solar cell. This distributed electrical network is based on two-diodes circuit elementary units. It allows accounting for the resistive losses due to the transport through the emitter, the back surface field (BSF) and the fingers and busbars metallization. Moreover, it can model the electrical shading losses attributed to the BSF busbar. We calibrated the electrical components of the model according to experimental measurements on real devices. The validity of the model is demonstrated by the good agreement between simulation and experimental results for dark and illuminated IV measurements with and without masked busbars. The model can now easily be applied to simulate and optimize different metal grid layouts. (C) 2014 The Authors. Published by Elsevier Ltd.