Early experiences with UK round 1 offshore wind farms

The UK government plans that offshore wind power should play a major part in meeting the UK’s renewable energy and carbon emission targets by 2020. The pioneer UK round 1 offshore wind farm projects, based on sites let in 2001, were supported by the UK Department of Trade and Industry’s ‘Offshore wind capital grants scheme’. Round 2 offshore sites were let in 2003 and the successful bidders for round 3 offshore sites were announced in January 2010; therefore the published reports from round 1 could provide valuable information on offshore experiences for the operation of later rounds. This paper reviews the performances of those UK round 1 offshore wind farms during their early operation based on published reports from the ‘Offshore wind capital grants scheme’ available for the period 2004–2007 and early operational issues. UK round 1 offshore wind farms have achieved an average cost of energy of £69 per MWh, in line with expectations, but at 80·3% the average availability fell short of expectations. The availability of UK round 1 offshore wind farms has been shown to decrease with increasing wind speed therefore it is recommended that improvements of availability at wind speeds of 7–14 m/s will be needed to meet more ambitious economic targets.