The paper presents the results of a life cycle assessment (LCA) of the electric generation by means of photovoltaic panels. It considers
mass and energy flows over the whole production process starting from silica extraction to the final panel assembling, considering the
most advanced and consolidate technologies for polycrystalline silicon panel production. Some considerations about the production
cycle are reported; the most critical phases are the transformation of metallic silicon into solar silicon and the panel assembling. The
former process is characterised by a great electricity consumption, even if the most efficient conversion technology is considered, the
latter by the use of aluminium frame and glass roofing, which are very energy-intensive materials. Moreover, the energy pay back time
(EPBT) and the potential for CO2 mitigation have been evaluated, considering different geographic collocations of the photovoltaic plant
with different values of solar radiation, latitude, altitude and national energetic mix for electricity production
