Life cycle assessment of a 150 MW offshore wind turbine farm at Nysted/Roedsand, Denmark

Abstract

The purpose of this life cycle assessment (LCA) was to illuminate and describe the potential environmental impacts caused by an offshore wind turbine farm (WTF) throughout its lifetime and use this knowledge in the planning and improvement of future WTFs. The LCA was based on experience from the LCA on Danish electricity and district heating [1] as well as the offshore WTF project at Middelgrunden which is in operation. LCA of a wind turbine is not new. However, development in the area of wind turbines at sea and transmission of the electricity from the offshore WTF is new, and therefore, focus on the advantages and disadvantages in comparison with wind turbines on land is necessary. Data from the current wind turbine project, Middelgrunden, near Copenhagen, was collected from SEAS' wind energy centre and the other participating organisations and extrapolated in order to reflect the offshore WTF at Nysted/Roedsand. Nysted/Roedsand is expected to be in operation by the year 2003. All of the components of the WTF and transmission facilities have been examined and areas of environmental improvement have been identified. It was found that Nysted/Roedsand's offshore WTF and associated transmission facilities per produced kilowatt-hour have an improved environmental profile in comparison with a land wind turbine. Areas of improvement of an offshore WTF include the recycling of metals, recycling of the wings, minimising resource consumption and increasing the life expectancy of the entire wind turbine. The ISO 14040 standard on LCA was followed and the EDIP (Environmental Design of Industrial Products) method and modelling tool were used [2].