Methodology for optimal allocation and sizing of photovoltaic and aeolic parks using geographical information systems: Case study in the Perfecture of Thessaly

Following the legislative EU targets and taking advantage of its high renewable energy potential, Greece can obtain significant benefits from developing its water, solar and wind energy resources. However, a holistic spatial planning approach that accounts for the possible land use conflicts and environmental impacts of RES (Renewable Energy Sources) is essential for their sustainable development. In this context, we present a GIS-based methodology for the optimal sizing and siting of solar and wind energy systems at the regional scale, which is tested in the Prefecture of Thessaly. In order to apply the methodology, we assess the wind and solar potential of the area, taking into account the stochastic nature of the associated meteorological processes (i.e. wind speed and solar radiation, respectively), which is essential component for both planning (i.e., type selection and sizing of photovoltaic panels and wind turbines) and management purposes (i.e., real-time operation of the system). For the optimal siting methodology, we account for a number of constraints, associated with technical limitations (e.g., terrain slope, proximity to road and electricity grid network, etc.), the environmental legislation and other land use constraints. Based on this analysis, we investigate favorable alternatives using technical, environmental as well as aesthetic criteria. The final outcome is GIS maps that depict the available energy potential and the optimal layout for photovoltaic panels and wind turbines over the study area. The present methodology could serve several purposes, since it can be applied for both the assessment and planning of the possible installed RES power and as a post-evaluation tool for the already licensed RES installations. The results could also be of particular use, in order to assume the combined operation of the above renewables with major hydroelectric dams and pumped-storage facilities, and thus provide a unique hybrid renewable system, extended at the regional scale.