Ecodesign of photovoltaic grid-connected systems

Optimization approaches for PV grid-connected system (PVGCS) have focused on optimizing the technical and economic performances. The main objective of this study is thus to propose an integrated framework that manages simultaneously technical, economic and environmental criteria. Life Cycle Assessment (LCA) is applied for the evaluation of environmental impacts of PVGCS. The proposed framework involves a PVGCS sizing simulator involving the computation of solar irradiance coupled to an outer optimization loop, based on a Genetic Algorithm. The objective is to maximize the annual energy generated by the facility. The analysis was carried out for different types of solar panel technologies: monocrystalline silicon (m-Si), polycrystalline silicon (p-Si), amorphous silicon (a-Si), cadmium telluride (CdTe) and copper indium diselenide (CIS). The environmental impact assessment was achieved by use of the IMPACT 2002+ method embedded in the SimaPro software tool with Ecoinvent database. The other chosen criteria based on technical and economic aspects concern the payback time of investment (PBT) and energy payback time (EPBT). To select the best option among the five choices under study, a weighted evaluation is performed on all criteria in order to obtain a score for each technology. The technology with the lowest total score is the a-Si technology. A more relevant analysis is then performed taking into account the environmental impacts per kWh produced, as new criteria. In this case, the CIS PV module technology best meets the objectives. (C) 2013 Elsevier Ltd. All rights reserved.