Screening Environmental Risk Assessment of Grease and Oil Emissions from Off-Shore Wind Power Plants

Report, 2012

This report constitutes a generic environmental risk assessment of emissions of grease and oil from off-shore wind power plants. In this context, risk is defined as an exposure of a stressor high enough to cause adverse effects on a certain endpoint. The stressors considered are alkanes, phosphate isodecyl/phenyl compounds and zinc alkyl dithiophosphate. The endpoints considered are the aquatic organisms fish, Daphnia magna, algae and aquatic bacteria. A screening risk assessment method is applied, assuming one-time releases of lubricant and gear oil. Although this should be seen as an early screening study, it indicates that the stressors included constitute risks to aquatic organisms given the setup of this study. A one-by-one parameter sensitivity analysis is performed to investigate the impact of different emissions, evaporation and biodegradation on the results. Even with low emissions, high evaporation and high biodegradation, the results show that the organisms living close to the wind power plant are subject to risk. The implications of these results if taken into account that some off-shore wind power plants may not occur one-by-one but rather be part of parks containing tens of plants together are discussed. Recommendations to reduce the risk are given. A technical risk reduction measure is to use less toxic, biodegradable lubricants. An organizational risk reduction measure is to increase maintenance and thereby reducing the likelihood of emissions occurring.