Influence of Site Specific Parameters on Environmental Performance of Wind Energy Converters

Wind energy is supposed to provide the world with “clean” energy, reducing the emission of anthropogenic greenhouse gases and other environmental impacts. While the energy produced in the use phase of wind energy converters (WEC) is as good as carbon neutral there are environmental impacts coming from production, transport and disposal of the WEC. Here the question about the WEC's energy and CO2 balance comes up. For different converters, indicators like the CO2e emissions per kWh (i.e. the carbon footprint), the energetic payback time and the harvest factor can be found in the literature. Since the underlying assumptions, boundary conditions, etc. will –in most cases- differ from each other, the results have only very limited comparability and allow drawing only general conclusions. Key indicators like the mentioned CO2e emissions per kWh, the energetic payback time, etc. will vary for each of the assessed converters individually, depending on the respective site. Factors like length of access roads and grid connection, size and depths of foundation, or wind conditions have an influence on the LCA results. Here, an assessment of a 2.3 MW wind energy converter at different sites will be presented, demonstrating which site specific factors are negligible and which are crucial for the environmental performance. Each aspect will be varied ceteris paribus showing the impact of every parameter individually.