Condition monitoring techniques for offshore wind farms

Offshore wind energy can contribute significantly towards enabling the EU reach the White Paper Target of 40GW of renewables by 2010. In order to achieve this, measures are required to stimulate offshore exploitation, with, in the short-term, wind turbines, which have improved durability, availability and reliability. Cost-effective wind turbine components are required and the overall cost of turbine generation and operation and maintenance costs need to be reduced. Operation and maintenance costs of an offshore wind farm are substantially greater than that of an onshore site. The utilisation of preventative maintenance and condition monitoring techniques can aid in maximising wind farm production and availability and in reducing operation and maintenance costs. This paper reviews recent literature on offshore win technology and theory applicable to the offshore wind resource. Primary influences which need to be accounted for when developing condition monitoring techniques for offshore in farms are described and recommendations are made with respect to preventative maintenance an condition monitoring system suitable for offshore applications. Such a system can contribute towards improving offshore turbine performance, availability and reliability.