Europe is the world leader in offshore wind energy. Due to the European Union's renewable energy and climate goals and national legislation the offshore wind sector will develop strongly in coming years in Europe. In northern sea areas there are special conditions that regulate the risks in design and deployment decisions for wind energy production. Moreover, in the current floating offshore wind mill design concepts system risks may also vary due to multiple influences of numerous risk factors in comparison to onshore wind mills. The focus in this paper is on system risks of offshore wind farms. It aims to bring a systematic risk management approach into perspective to support wind farm design and deployment process under challenging Nordic conditions. This approach is based on the system lifecycle model, risk influence factors, and generic risk management framework. The overall view of the risks inherent in a wind farm project is presented, but the perspective in this paper is limited to risks affecting system availability and system safety of offshore wind farms.
The Nordic countries have been assiduous in adapting wind energy as the future energy solution for the region. As of 2010, there are 39 European offshore wind farms in waters off Belgium, Denmark, Finland, Germany, Ireland, the Netherlands, Norway, Sweden and the United Kingdom, having together 3.16 GW of offshore operational wind power capacity. In the largest offshore wind farm there are 100 individual wind turbines. More than 100 GW (or 100,000 MW) of offshore projects are proposed or under development in Europe. The European Wind Energy Association has set a target of 40 GW installed by 2020 and 150 GW by 2030. (EESI, 2010) According to EWEA (2009) wind farm design is a critical area for cost reduction and public acceptability, both onshore and offshore.