Offshore wind power

Offshore wind power or offshore wind energy is the use of wind farms constructed in bodies of water, usually in the ocean on the continental shelf, to harvest wind energy to generate electricity. Higher wind speeds are available offshore compared to on land, so offshore wind power’s electricity generation is higher per amount of capacity installed, and NIMBY opposition to construction is usually much weaker.Unlike the typical use of the term 'offshore' in the marine industry, offshore wind power includes inshore water areas such as lakes, fjords and sheltered coastal areas, utilizing traditional fixed-bottom wind turbine technologies, as well as deeper-water areas utilizing floating wind turbines. Offshore wind power or offshore wind energy is the use of wind farms constructed in bodies of water, usually in the ocean on the continental shelf, to harvest wind energy to generate electricity. Higher wind speeds are available offshore compared to on land, so offshore wind power’s electricity generation is higher per amount of capacity installed, and NIMBY opposition to construction is usually much weaker.Unlike the typical use of the term 'offshore' in the marine industry, offshore wind power includes inshore water areas such as lakes, fjords and sheltered coastal areas, utilizing traditional fixed-bottom wind turbine technologies, as well as deeper-water areas utilizing floating wind turbines. At the end of 2017, the total worldwide offshore wind power capacity was 18.8 GW. All the largest offshore wind farms are currently in northern Europe, especially in the United Kingdom and Germany, which together account for over two thirds of the total offshore wind power installed worldwide. As of September 2018, the 659 MW Walney Extension in the United Kingdom is the largest offshore wind farm in the world. The Hornsea Wind Farm under construction in the United Kingdom will become the largest when completed, at 1,200 MW. Other projects are in the planning stage, including Dogger Bank in the United Kingdom at 4.8 GW, and Greater Changhua in Taiwan at 2.4 GW. The cost of offshore wind power has historically been higher than that of onshore wind generation, but costs have been decreasing rapidly in recent years and in Europe has been price-competitive with conventional power sources since 2017. Europe is the world leader in offshore wind power, with the first offshore wind farm (Vindeby) being installed in Denmark in 1991. In 2009, the average nameplate capacity of an offshore wind turbine in Europe was about 3 MW, and the capacity of future turbines was expected to increase to 5 MW. In 2010, the US Energy Information Agency said 'offshore wind power is the most expensive energy generating technology being considered for large scale deployment'.The 2010 state of offshore wind power presented economic challenges significantly greater than onshore systems, with prices in the range of 2.5-3.0 million Euro/MW. That year, Siemens and Vestas were turbine suppliers for 90% of offshore wind power, while DONG Energy, Vattenfall and E.on were the leading offshore operators. In 2011, DONG Energy estimated that while offshore wind turbines were not yet competitive with fossil fuels, they would be in 15 years. Until then, state funding and pension funds would be needed. At the end of 2011, there were 53 European offshore wind farms in waters off Belgium, Denmark, Finland, Germany, Ireland, the Netherlands, Norway, Sweden and the United Kingdom, with an operating capacity of 3,813 MW, while 5,603 MW was under construction.Offshore wind farms worth €8.5 billion ($11.4 billion) were under construction in European waters in 2011. In 2012, Bloomberg estimated that energy from offshore wind turbines cost €161 (US$208) per MWh. A 2013 comprehensive review of the engineering aspects of turbines like the sizes used onshore, including the electrical connections and converters, considered that the industry had in general been overoptimistic about the benefits-to-costs ratio and concluded that the 'offshore wind market doesn’t look as if it is going to be big'.In 2013, offshore wind power contributed to 1,567 MW of the total 11,159 MW of wind power capacity constructed that year. By January 2014, 69 offshore wind farms had been constructed in Europe with an average annual rated capacity of 482 MW. The total installed capacity of offshore wind farms in European waters reached 6,562 MW.The United Kingdom had by far the largest capacity with 3,681 MW. Denmark was second with 1,271 MW installed and Belgium was third with 571 MW. Germany came fourth with 520 MW, followed by the Netherlands (247 MW), Sweden (212 MW), Finland (26 MW), Ireland (25 MW), Spain (5 MW), Norway (2 MW) and Portugal (2 MW).