The new study by the bifa environmental institute describes a future-orientated view of the ecological and economic effects of photovoltaic (PV) systems along their whole life cycle.
The study evaluated the production of the PV systems, their operation in different application cases and different recycling scenarios. Wafer and thin- film technologies were examined. The evaluation was made not only as a snapshot of the present time, but also describes the potential of medium-term developments. The study was carried out on behalf of the Bavarian State Ministry of the Environment and Consumer Protection (“Bayerisches Staatsministerium für Umwelt und Verbraucherschutz”) and was supported by a large number of companies in the photovoltaics industry.
PV is a particularly environmentally friendly form of electricity generation, whose environmental effect (among other things: climate change, acid rain, resource consumption) is a factor of 10 to 20 lower than for electricity generation with fossil fuels. Apart from the environmental assessment, “electricity from PV” and “electricity from fossil fuels” also differ with regard to several characteristics such as controllability. Against this background, the environmental differences of the PV technologies examined are only small. However, the causes of the environmental results vary due to the fundamentally different production of wafer-based and substrate-coated modules/laminates. In the costs analysis the focus is not on the PV technologies but on their use in different application cases.
The use of PV on large roofs has the best environmental assessment due to the use of existing infrastructure (e.g. roof slope or grid connection). By comparison, outdoor systems in fields perform somewhat worse due to the disproportionate cost of the other system components (e.g. substructure and cabling). Depending on the application case and technology, the energy payback periods for the PV systems lie between 0.6 and 1.3 years. The potential for successful implementation of an integrated and technologically high-quality recycling system proves to be significant from an environmental point of view. For wafer-based modules, for example, more than 20 % of the environmental costs from the production can be saved.
