Offshore wind power

Wind turbines and electrical substation of Alpha Ventus supplied by Adwen in the North Sea
Four offshore wind farms are in the Thames Estuary area: Kentish Flats, Gunfleet Sands, Thanet and London Array. The latter is the largest in the world as of April 2013.

Offshore wind power or offshore wind energy is the use of wind farms constructed offshore, usually 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 contribution in terms of electricity supplied is higher,[1] and NIMBY opposition to construction is usually much weaker. The cost of offshore wind power has historically been higher than that of onshore wind generation,[2] but in 2016 had decreased to €54.5/MWh the 700 MW Borssele 3&4[3] due to government tender and size.[4] Similarly, €49.90/MWh ($55.34, without transmission) was achieved at the 600 MW Kriegers Flak.[5]

As of 2017, the 630 megawatt (MW) London Array in the United Kingdom is the largest offshore wind farm in the world. All the largest offshore wind farms are currently in northern Europe. Larger projects are in the planning stage, including Dogger Bank at 4,800 MW, Norfolk Bank (7,200 MW), and Irish Sea (4,200 MW). At the end of June 2013 total European combined offshore wind energy capacity was 6,040 MW. UK installed 513.5 MW offshore windpower in the first half year of 2013.[6]

Definition

Progression of expected wind turbine evolution to deeper water.

Offshore wind power refers to the construction of wind farms in bodies of water to generate electricity from wind. Unlike the typical usage 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.

The U.S. National Renewable Energy Laboratory has further defined offshore wind power based on its siting in terms water depth to include shallow water, transitional water, and deep water offshore wind power.

History

2,500
5,000
7,500
10,000
12,500
15,000
1998
2002
2006
2010
2014
Global cumulative offshore capacity (in megawatts).
Sources: GWEC (2011–2016)[7][8][9] and EWEA (1998–2010)[10]

Europe is the world leader in offshore wind power, with the first offshore wind farm (Vindeby) being installed in Denmark in 1991.[11] In 2013, offshore wind power contributed to 1,567 MW of the total 11,159 MW of wind power capacity constructed that year.[12] By January 2014, 69 offshore wind farms had been constructed in Europe with an average annual rated capacity of 482 MW in 2013,[13] and as of January 2014 the United Kingdom has by far the largest capacity of offshore wind farms with 3,681 MW. Denmark is second with 1,271 MW installed and Belgium is third with 571 MW. Germany comes 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).[13] By January 2014, the total installed capacity of offshore wind farms in European waters had reached 6,562 MW.[13]

By 2015, Siemens Wind Power had installed 63% of the world's 11 GW[14] offshore wind power capacity; Vestas had 19%, Senvion comes third with 8% and Adwen 6%.[15]

Projections for 2020 calculate a wind farm capacity of 40 GW in European waters, which would provide 4% of the European Union's demand of electricity.[16]

The Chinese government has set ambitious targets of 5 GW of installed offshore wind capacity by 2015 and 30 GW by 2020 that would eclipse capacity in other countries. In May 2014 the capacity of offshore wind power in China was 565 MW.[17] Offshore capacity increased by 832 MW in 2016, of which 636 MW were made in China.[18]

Fixed foundation offshore wind farms

As of 2010 Siemens and Vestas were turbine suppliers for 90% of offshore wind power, while Dong Energy, Vattenfall and E.on were the leading offshore operators.[1] As of 1 January 2016, about 12 gigawatts (GW) of offshore wind power capacity was operational, mainly in Northern Europe, with 3,755 MW of that coming online during 2015.[19] According to BTM Consult, more than 16 GW of additional capacity will be installed before the end of 2014 and the United Kingdom and Germany will become the two leading markets. Offshore wind power capacity is expected to reach a total of 75 GW worldwide by 2020, with significant contributions from China and the United States.[1]

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,[20] while 5,603 MW is under construction.[21] 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.[11]

As of July 2013, the 175-turbine London Array in the United Kingdom is the largest offshore wind farm in the world with a capacity of 630 MW, followed by Greater Gabbard (504 MW), also in the United Kingdom, Anholt (400 MW) in Denmark, and BARD Offshore 1 (400 MW) in Germany. There are many large offshore wind farms under construction including Gwynt y Môr (576 MW), Borkum West II (400 MW), and West of Duddon Sands (389 MW). Offshore wind farms worth some €8.5 billion ($11.4 billion) were under construction in European waters in 2011. Once completed, they will represent an additional installed capacity of 2,844 MW.[22]

At the end of 2014, 3,230 turbines at 84 offshore wind farms across 11 European countries had been installed and grid-connected, making a total capacity of 11,027 MW.[23]

China has two operational offshore wind farms of 131 MW[24][25] and 101 MW capacity.[26][27]

Largest offshore wind farms

World's largest offshore wind farms
Wind farm Capacity (MW) Country Turbines and model Commissioned Refs
London Array 630 United Kingdom 175 × Siemens SWT-3.6 2012 [28][29][30]
Gemini Wind Farm 600 Netherlands 150 × Siemens SWT-4.0 2017 [31][32][33][34]
Greater Gabbard 504 United Kingdom 140 × Siemens SWT-3.6 2012 [35]
Anholt 400 Denmark 111 × Siemens SWT-3.6-120 2013 [36]
BARD Offshore 1 400 Germany 80 × BARD 5.0 turbines 2013 [37]
Walney 367 United Kingdom 102 × Siemens SWT-3.6 2012 [38][39]
Thorntonbank 325 Belgium 54 × Senvion 6 MW 2013 [40]
Sheringham Shoal 317 United Kingdom 88 × Siemens 3.6 2013 [41]
Thanet 300 United Kingdom 100 × Vestas V90-3MW 2010 [42][43]
Meerwind Süd/Ost 288 Germany 80 × Siemens SWT-3.6-120 2014 [44][45]
Lincs 270 United Kingdom 75 × Siemens 3.6 2013 [46]
Horns Rev II 209 Denmark 91 × Siemens 2.3-93 2009 [47]

Projects

Canadian wind power in the province of Ontario is pursuing several proposed locations in the Great Lakes, including the suspended[48] Trillium Power Wind 1 approximately 20 km from shore and over 400 MW in capacity.[49] Other Canadian projects include one on the Pacific west coast.[50]

India is looking at the potential of off-shore wind power plants, with a 100 MW demonstration plant being planned off the coast of Gujarat (2014).[51] In 2013, a group of organizations, led by Global Wind Energy Council (GWEC) started project FOWIND (Facilitating Offshore Wind in India) to identify potential zones for development of off-shore wind power in India and to stimulate R & D activities in this area. In 2014 FOWIND commissioned Center for Study of Science, Technology and Policy (CSTEP) to undertake pre-feasibility studies in eight zones in Tamil Nadu which have been identified as having potential.[52]

As of 2015, there are no offshore wind farms in the United States. However, projects are under development in wind-rich areas of the East Coast, Great Lakes, and Pacific coast. In January 2012, a "Smart for the Start" regulatory approach was introduced, designed to expedite the siting process while incorporating strong environmental protections. Specifically, the Department of Interior approved “wind energy areas” off the coast where projects can move through the regulatory approval process more quickly.[53] The first offshore wind farm in the USA is the 30-megawatt, 5 turbine Block Island Wind Farm which was commissioned in December 2016.[54][55]

Deeper water offshore wind farms

Hywind is the world's first full-scale floating wind turbine, installed in the North Sea off Norway in 2009.[56] Other kinds of floating turbines have been deployed, and more projects are planned.

New England Aqua Ventus I, Maine, United States (Planned, 2018-2019)

The patent-pending VolturnUS floating concrete hull technology can support wind turbines in water depths of 45 meters or more, and has the potential to significantly reduce the cost of offshore wind. This technology was developed by the UMaine Advanced Structures and Composites Center.

New England Aqua Ventus I is a two 6 MW turbine (12 MW) floating offshore wind pilot project ~25 km off Maine’s coast near Monhegan Island, developed by Maine Aqua Ventus, GP, LLC.[57] This pilot project utilizes the University of Maine's patent-pending VolturnUS, a floating concrete hull technology can support wind turbines in water depths of 45 meters or more. The objective of the pilot is to demonstrate the technology at full scale, allowing floating farms to be built out-of-sight across the US and the world in the 2020s. New England Aqua Ventus I Project partners include Emera Inc., Cianbro Corporation, University of Maine and its Advanced Structures and Composites Center, and DCNS.[58]

This pilot project is planned for deployment in 2018-2019 at the University of Maine's Deepwater Offshore Wind Test Site designated by the State of Maine during the 124th Legislature.[59]

Offshore wind turbines near Copenhagen, Denmark

Economics and benefits

Current conditions

Offshore wind power can help to reduce energy imports, reduce air pollution and greenhouse gases (by displacing fossil-fuel power generation), meet renewable electricity standards, and create jobs and local business opportunities.[11] The advantage is that the wind is much stronger off the coasts, and unlike wind over the continent, offshore breezes can be strong in the afternoon, matching the time when people are using the most electricity. Offshore turbines can also be "located close to the power-hungry populations along the coasts, eliminating the need for new overland transmission lines".[60]

Most entities and individuals active in offshore wind power believe that prices of electricity will grow significantly from 2009, as global efforts to reduce carbon emissions come into effect. BTM expects cost per kWh to fall from 2014,[61] and that the resource will always be more than adequate in Europe, the United States and China.[1]

The turbine represents just one third to one half[62] of costs in offshore projects today, the rest comes from infrastructure, maintenance, and oversight. Larger turbines with increased energy capture make more economic sense due to the extra infrastructure in offshore systems. Additionally, there are currently no rigorous simulation models of external effects on offshore wind farms, such as boundary layer stability effects and wake effects. This causes difficulties in predicting performance accurately, a critical shortcoming in financing billion-dollar offshore facilities. A report from a coalition of researchers from universities, industry, and government, lays out several things needed in order to bring the costs down and make offshore wind more economically viable:

Research and development projects aim to address these issues. One example is the Carbon Trust Offshore Wind Accelerator, a joint industry project, involving nine offshore wind developers, which aims to reduce the cost of offshore wind by 10% by 2015. It has been suggested that innovation at scale could deliver 25% cost reduction in offshore wind by 2020.[64]

Locating wind turbines offshore exposes the units to high humidity, salt water and salt water spray which negatively affect service life, cause corrosion and oxidation, increase maintenance and repair costs and in general make every aspect of installation and operation much more difficult, time-consuming, more dangerous and far more expensive than sites on land. The humidity and temperature is controlled by air conditioning the sealed nacelle.[65]

The offshore wind industry is not fully industrialized, as supply bottlenecks still exist as of 2017.[66] Monopiles up to 11 m diameter at 2,000 tonnes can be made, but the largest so far are 1,300 tonnes which is below the 1,500 tonnes limit of some crane vessels. The other turbine components are much smaller.[67]

Higher wind speeds do not automatically result in increased electricity generation. Wind turbines are limited by the maximum wind speeds their mechanical and electrical components can reliably and durably operate at. Wind speeds above those limits result in the wind turbine adjusting its blade angles to reduce generator speed or in some cases shutting down entirely. Sustained high-speed operation and generation increases wear, maintenance and repair requirements proportionally and invariably costs are additionally and significantly increased by the location offshore.

For example, a single technician in a pickup truck can quickly, easily and safely access turbines on land in almost any weather conditions, exit his or her vehicle and simply walk over to and into the turbine tower to gain access to the entire unit within minutes of arriving onsite. Similar access to offshore turbines involves driving to a dock or pier, loading necessary tools and supplies into boat, a voyage to the wind turbine(s), securing the boat to the turbine structure, transferring tools and supplies to and from boat to turbine and turbine to boat and performing the rest of the steps in reverse order. In addition to standard safety gear such as a hardhat, gloves and safety glasses, an offshore turbine technician may be required to wear a life vest, waterproof or water-resistant clothing and perhaps even a survival suit if working, sea and atmospheric conditions make rapid rescue in case of a fall into the water unlikely or impossible.

Typically at least two technicians skilled and trained in operating and handling large power boats at sea are required for tasks that one technician with a driver's license can perform on land in a fraction of the time at a fraction of the cost.

Past conditions and predictions

Levelized cost of offshore wind power compared to other sources (Germany, November 2013)

In 2010, the US Energy Information Agency said "offshore wind power is the most expensive energy generating technology being considered for large scale deployment".[2] The 2010 state of offshore wind power presented economic challenges significantly greater than onshore systems - prices could be in the range of 2.5-3.0 million Euro/MW.[62]

In 2011, a Danish energy company claimed that offshore wind turbines are not yet competitive with fossil fuels, but estimated that they would be in 15 years. Until then, state funding and pension funds would be needed.[68] In 2012, Bloomberg estimated that energy from offshore wind turbines cost €161 (US$208) per MWh.[69]

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".[70][71]

In 2015, industry experts were asked about future development of offshore wind power prices.[72] By 2016, four contracts (Borssele and Kriegers) were already below the lowest of the predicted 2050 prices.[73][74]

The Organisation for Economic Co-operation and Development (OECD) predicted in 2016 that offshore wind power will grow to 8% of ocean economy by 2030, and that its industry will employ 435,000 people, adding $230 billion of value.[75]

Maintenance and decomissioning

As the first Offshore Windfarms move beyond their initial Warranty periods with the Turbine Equipment Manufacturer, an increase in alternative Operations and Maintenance support options is evident. Alternative suppliers of spare parts are entering the market and others are offering niche products and services many of which are focused on improving the power production volumes from these large renewable energy power plants.[76]

As the first offshore wind farms reach their end of life, a demolition industry develops to recycle them at a cost of DKK 2-4 million per MW, to be guaranteed by the owner.[77]

Technical details

In 2009, the average nameplate capacity of an offshore wind turbine in Europe was about 3 MW, and the capacity of future turbines is expected to increase to 5 MW.[11]

Design environment

Offshore wind turbines in Fehmarn Belt, the western part of the Baltic Sea between Germany and Denmark (2010)

Offshore wind resource characteristics span a range of spatial and temporal scales and field data on external conditions. For the North Sea, wind turbine energy is around 30 kWh/m2 of sea area, per year, delivered to grid. The energy per sea area is roughly independent of turbine size.[78] Necessary data includes water depth, currents, seabed, migration, and wave action, all of which drive mechanical and structural loading on potential turbine configurations. Other factors include marine growth, salinity, icing, and the geotechnical characteristics of the sea or lake bed. A number of things are necessary in order to attain the necessary information on these subjects. Existing hardware for these measurements includes Light Detection and Ranging (LIDAR), Sonic Detection and Ranging (SODAR), radar, autonomous underwater vehicles (AUV), and remote satellite sensing, although these technologies should be assessed and refined, according to a report from a coalition of researchers from universities, industry, and government, supported by the Atkinson Center for a Sustainable Future.[63]

Because of the previous factors, one of the biggest difficulties with offshore wind farms is the ability to predict loads. Analysis must account for the dynamic coupling between translational (surge, sway, and heave) and rotational (roll, pitch, and yaw) platform motions and turbine motions, as well as the dynamic characterization of mooring lines for floating systems. Foundations and substructures make up a large fraction of offshore wind systems, and must take into account every single one of these factors.[63] Load transfer in the grout between tower and foundation may stress the grout, and elastomeric bearings are used in several British sea turbines.[79]

Corrosion is also a serious problem and requires detailed design considerations. The prospect of remote monitoring of corrosion looks very promising using expertise utilised by the offshore oil/gas industry and other large industrial plants.

Some of the guidelines for designing offshore wind farms are IEC 61400-3,[80][81][82] but in the US several other standards are necessary.[83] In the EU, different national standards are to be straightlined into more cohesive guidelines to lower costs.[84] The standards requires that a loads analysis is based on site-specific external conditions such as wind, wave and currents.[85]

Planning

Offshore turbines require different types of bases for stability, according to the depth of water. To date a number of different solutions exist:

The planning and permitting phase can cost more than $10 million, take 5–7 years and have an uncertain outcome. The industry puts pressure on the governments to improve the processes.[91][92] In Denmark, many of these phases have been deliberately streamlined by authorities in order to minimize hurdles,[93] and this policy has been extended for coastal wind farms with a concept called ’one-stop-shop’.[94] USA introduced a similar model called "Smart from the Start" in 2012.[95]

Maintenance

Turbines are much less accessible when offshore (requiring the use of a service vessel or helicopter for routine access, and a jackup rig for heavy service such as gearbox replacement), and thus reliability is more important than for an onshore turbine.[1] Some wind farms located far from possible onshore bases have service teams living on site in offshore accommodation units.[96]

A maintenance organization performs maintenance and repairs of the components, spending almost all its resources on the turbines. The conventional way of inspecting the blades is for workers to rappel down the blade, taking a day per turbine. Some farms inspect the blades of three turbines per day by photographing them from the monopile through a 600mm lens, avoiding to go up.[97] Others use camera drones.[98]

Because of their remote nature, prognosis and health-monitoring systems on offshore wind turbines will become much more necessary. They would enable better planning just-in-time maintenance, thereby reducing the operations and maintenance costs. According to a report from a coalition of researchers from universities, industry, and government (supported by the Atkinson Center for a Sustainable Future),[63] making field data from these turbines available would be invaluable in validating complex analysis codes used for turbine design. Reducing this barrier would contribute to the education of engineers specializing in wind energy.

Environmental impact

While the offshore wind industry has grown dramatically over the last several decades, especially in Europe, there is still a great deal of uncertainty associated with how the construction and operation of these wind farms affect marine animals and the marine environment.[99]

Common environmental concerns associated with offshore wind developments include:

The Tethys database provides access to scientific literature and general information on the potential environmental effects of offshore wind energy.[100]

See also

References

  1. 1 2 3 4 5 Madsen & Krogsgaard. Offshore Wind Power 2010 Archived June 30, 2011, at the Wayback Machine. BTM Consult, 22 November 2010. Retrieved: 22 November 2010.
  2. 1 2 Levelized Cost of New Generation Resources in the Annual Energy Outlook 2011. Released December 16, 2010. Report of the US Energy Information Administration (EIA) of the U.S. Department of Energy (DOE).
  3. ↑ "Oil & Gas Giant to Build Dutch Borssele III & IV Offshore Wind Farms". Offshore Wind. 12 December 2016. Retrieved 14 December 2016.
  4. ↑ "Tender design, output gains key to DONG’s record-low Borssele 1&2 offshore bid price". 17 August 2016. Archived from the original on 17 September 2016. Retrieved 17 September 2016.
  5. ↑ Steel, William (9 November 2016). "Vattenfall wins Kriegers Flak with record €49.90/MWh". Recharge. Archived from the original on 10 November 2016. Retrieved 10 November 2016.
  6. ↑ The European offshore wind industry -key trends and statistics 1st half 2013 EWEA 2013
  7. ↑ "GWEC Global Wind Statistics 2014" (PDF). Global Wind Energy Council. 10 February 2015.
  8. ↑ "Global Wind Statistics 2015" (PDF). Global Wind Energy Council (GWEC). 10 February 2016. Retrieved 14 April 2017.
  9. ↑ "OFFSHORE WIND | GWEC". www.gwec.net. Retrieved 5 August 2017.
  10. ↑ "Wind in our Sails, A report by the European Wind Energy Association - 2011" (PDF). European Wind Energy Association. 2011. p. 11. Retrieved 27 February 2015.
  11. 1 2 3 4 5 Environmental and Energy Study Institute (October 2010). "Offshore Wind Energy" (PDF).
  12. ↑ "Wind in power 2013 European statistics" The European Wind Energy Association, 2014
  13. 1 2 3 The European offshore wind industry - key trends and statistics 2013 ,The European Wind Energy Association, 2014
  14. ↑ Ryan, Joe (2 May 2016). "A U.S. State Has Key to $10 Billion Offshore Wind Boom". Bloomberg.com. Retrieved 2 June 2016.
  15. ↑ Jessica Shankleman (28 April 2016). "World's Biggest Windmills Now Make Jumboi Jets Look Tiny". Bloomberg.com. Retrieved 2 June 2016.
  16. ↑ Tillessen, Teena (2010). "High demand for wind farm installation vessels". Hansa International Maritime Journal. Vol. 147 no. 8. pp. 170–171.
  17. ↑ "Detailed appraisal of the offshore wind industry in China". The Carbon Trust. May 2014. Retrieved 22 July 2014.
  18. ↑ "China tops offshore turbine chart". reNEWS - Renewable Energy News. 22 February 2017. Retrieved 26 February 2017.
  19. ↑ "Global Wind Industry Hits Record 62 GW Installed In 2015". CleanTechnica.
  20. ↑ Justin Wilkes et al. The European offshore wind industry key 2011 trends and statistics European Wind Energy Association, January 2012. Accessed: 26 March 2012.
  21. ↑ 17 EU countries planning massive offshore wind power ROV world, 30 November 2011. Accessed: 10 December 2011.
  22. ↑ Tildy Bayar (30 September 2011). "Wind Energy Markets: Experts See Solid Offshore Growth". Renewable Energy World.
  23. ↑ "Wind in Power: 2014 European statistics". European Wind Energy Association (EWEA). Retrieved 2014-03-16.
  24. ↑ 5 January 2012 by Wu Qi , Be the first to comment (2012-01-05). "China's largest offshore project now online". Windpowermonthly.com. Retrieved 2013-07-06.
  25. ↑ "Xinhuanet: Pilot project paves way for China's offshore wind power boom". News.xinhuanet.com. 2012-01-03. Retrieved 2013-07-06.
  26. ↑ "Donghai Bridge at 4cOffshore". 4coffshore.com. Retrieved 2013-07-06.
  27. ↑ "Wind blows in energy for Shanghai". Retrieved 28 May 2015.
  28. ↑ "London Array's own website announcement of commencement of offshore works" (PDF). Retrieved 2013-07-06.
  29. ↑ Wittrup, Sanne. First foundation Ing.dk, 8 March 2011. Accessed: 8 March 2011.
  30. ↑ "London Array Project home page". Londonarray.com. 1999-02-22. Retrieved 2013-07-06.
  31. ↑ "E_Facts - figures". geminiwindpark.nl.
  32. ↑ "The 600-MW Gemini offshore wind farm is successfully up & running".
  33. ↑ https://renewablesnow.com/news/gemini-offshore-wind-project-fully-completed-567090/
  34. ↑ "Gemini". 4coffshore.com. Retrieved 4 September 2015.
  35. ↑ Greater Gabbard. "SSE wind farm Project Website". Sse.com. Retrieved 2013-07-06.
  36. ↑ DONG Energy. "Facts on Anholt Offshore Wind Farm". dongenergy.com. Retrieved 2014-02-02.
  37. ↑ BARD Offshore (2013-08-01). "Pioneering wind farm project BARD Offshore 1 successfully completed on the high seas". BARD Offshore. Retrieved 2014-08-21.
  38. ↑ "Walney". 4COffshore. 2012-02-09. Retrieved 2012-02-09.
  39. ↑ "World's biggest offshore wind farm opens off Britain as new minister admits high cost". The Telegraph. 2012-02-09. Retrieved 2012-02-09.
  40. ↑ "Belgium: Thornton Bank Offshore Wind Farm Officially Inaugurated". offshorewind.biz. 2013-09-18. Retrieved 2014-08-21.
  41. ↑ "Sheringham Shoal". scira.co.uk. Retrieved 2014-08-21.
  42. ↑ "Thanet". The Engineer Online. 2008-07-25. Retrieved 2008-11-26.
  43. ↑ "Thanet offshore wind farm starts electricity production". BBC News. 23 September 2010. Retrieved 2010-09-14.
  44. ↑ Meerwind Süd/Ost (Germany) offshore wind farm 4C . Retrieved: 14 December 2014.
  45. ↑ "Herzlich willkommen bei WindMW - Project MEERWIND Süd - Ost". Retrieved 28 May 2015.
  46. ↑ "Lincs OWF: Centrica Expresses Gratitude to Local Community (UK)". offshorewind.biz. 2013-07-04. Retrieved 2014-08-21.
  47. ↑ "Horns Rev II turbines". Dongenergy.com. Retrieved 2013-07-06.
  48. ↑ Offshore wind development hits a snag in Ontario Alberta Oil Magazine, April 2011. Accessed: 29 September 2011.
  49. ↑ Hamilton, Tyler (January 15, 2008). "Ontario to approve Great Lakes wind power". The Star. Toronto. Retrieved 2008-05-02.
  50. ↑ "Naikun Wind Development, Inc.". Retrieved 2008-05-21.
  51. ↑ "MOU Signed for First Ever Offshore Wind Power Project in India". www.pib.nic.in. Press Information Bureau, Government of India. October 1, 2014. Retrieved 30 April 2015.
  52. ↑ R. Srikanth; Sangeetha Kandavel (January 29, 2015). "Tapping the offshore wind". The Hindu. Retrieved 30 April 2015.
  53. ↑ Kit Kennedy (2 February 2012). "Offshore Wind One Step Closer to Reality in the Mid-Atlantic". Renewable Energy World.
  54. ↑ "America Is Finally Getting Its First Offshore Wind Farm. Conservatives Are Trying to Make Sure It’s the Last.". New Republic. 14 May 2015. Retrieved 15 May 2015.
  55. ↑ "Block Island Wind Farm - Deepwater Wind". Deepwater Wind. Retrieved 20 May 2016.
  56. ↑ Madslien, Jorn (5 June 2009). "Floating wind turbine launched". BBC News. Retrieved 14 September 2009.
  57. ↑ "The Project". Maine Aqua Ventus. Maine Aqua Ventus. Retrieved 5 July 2016.
  58. ↑ "Project Partners". Maine Aqua Ventus. Maine Aqua Ventus. Retrieved 5 July 2016.
  59. ↑ "An Act To Facilitate Testing and Demonstration of Renewable Ocean Energy Technology". 124th Maine Legislature. Maine State Legislature. Retrieved 5 July 2016.
  60. ↑ "Wind Power". New York Times. January 27, 2002.
  61. ↑ Madsen & Krogsgaard. Press offshore Archived July 19, 2011, at the Wayback Machine. (in Danish) BTM Consult, 22 November 2010. Retrieved: 22 November 2010.
  62. 1 2 Lindvig, Kaj. The installation and servicing of offshore wind farms p6 A2SEA, 16 September 2010. Accessed: 9 October 2011.
  63. 1 2 3 4 Zehnder, Alan; Warhaft, Zellman, eds. (2011). "University Collaboration on Wind Energy" (PDF). Cornell University. Retrieved 13 January 2016.
  64. ↑ "Offshore Wind Accelerator". The Carbon Trust. Retrieved 22 July 2014.
  65. ↑ Prinds, Karsten (20 April 2011). "Where offshore wind was invented". LORC. Archived from the original on 29 April 2016. Retrieved 27 February 2017.
  66. ↑ "Is the supply chain ready for the green transformation? The case of offshore wind logistics". Renewable and Sustainable Energy Reviews. 73: 758–771. 1 June 2017. doi:10.1016/j.rser.2017.01.181. Retrieved 16 March 2017 – via ScienceDirect.
  67. ↑ "Installation Vessels: Reaching the Limit and Beyond". Retrieved 19 April 2017.
  68. ↑ Nymark, Jens. Seaturbines competitive in 15 years Archived November 16, 2011, at the Wayback Machine. Børsen, 15 November 2011. Accessed: 10 December 2011.
  69. ↑ Bakewell, Sally (29 October 2012). "Largest Offshore Wind Farm Generates First Power in U.K.". Bloomberg. Retrieved 19 December 2012.
  70. ↑ Platt, Jim (2013). "The offshore wind energy nano-industry". Nanotechnology Perceptions. 9 (2): 91–95.
  71. ↑ "The offshore wind energy nano-industry". Retrieved 20 May 2016.
  72. ↑ Wiser, Ryan H., Karen Jenni, Joachim Seel, Erin Baker, Maureen M. Hand, Eric Lantz, and Aaron Smith (June 2016). "Forecasting Wind Energy Costs and Cost Drivers: The Views of the World’s Leading Experts". Nature Energy. Retrieved 21 December 2016. http://rdcu.be/khRk
  73. ↑ Stiesdal, Henrik (21 December 2016). "Midt i en disruptionstid". Ingeniøren. Retrieved 21 December 2016. Real prices have moved to half of what the experts predicted
  74. ↑ "Price diagram: Real and predicted prices for offshore wind power".
  75. ↑ The Ocean Economy in 2030, pp.205-212. OECD iLibrary, 27 April 2016. ISBN 9264251723 . Web read
  76. ↑ "What does successful operations & maintenance look like?". Retrieved 28 May 2015.
  77. ↑ "Aldrende havmølleparker åbner marked for klog nedrivning". Ingeniøren. Retrieved 20 May 2016.
  78. ↑ Stiesdal, Henrik. "Pi and turbines - a useful context" Original, in Danish Ingeniøren, 13 March 2015. Accessed: 13 March 2015.
  79. ↑ Tramontana, Tea (31 October 2012). "Overcoming problems with crumbling grout". LORC. Archived from the original on 12 May 2016. Retrieved 27 February 2017.
  80. ↑ "Wind turbines Part 3: Design requirements for offshore wind turbines" Austrian Standards Institute. Retrieved: 16 August 2012.
  81. ↑ International Standard IEC 61400-3 International Electrotechnical Commission, August 2005. Accessed: 12 March 2011.
  82. ↑ Quarton, D.C. "An international design standard for offshore wind turbines: IEC 61400-3" Archived July 21, 2011, at the Wayback Machine. Garrad Hassan, 2005. Accessed: 12 March 2011.
  83. ↑ Musial, W. D.; Sheppard, R. E.; Dolan, D.; Naughton, B. "Development of Offshore Wind Recommended Practice for U.S. Waters" National Renewable Energy Laboratory, April 2013. Accessed: 20 November 2013. OSTI ID: 1078076
  84. ↑ http://www.efkm.dk/nyheder/nyt-nordsoe-samarbejde-kan-goere-nordsoeen-silicon-valley-havvindmoeller
  85. ↑ Jonkman, J.M. "Dynamics Modeling and Loads Analysis of an Offshore Floating Wind Turbine" Technical Report NREL/TP-500-41958 page 75, NREL November 2007. Retrieved: 25 June 2012.
  86. ↑ "Support structure concepts for offshore wind turbines". LORC Knowledge. 2011-03-14. Retrieved 2011-06-01.
  87. ↑ "Design requirements for floating offshore wind turbines" International Electrotechnical Commission. Retrieved: 16 August 2012.
  88. ↑ "Classification and Certification of Floating Offshore Wind Turbines" Archived December 3, 2013, at the Wayback Machine. Bureau Veritas, November 2010. Retrieved: 16 August 2012.
  89. ↑ Elaine Kurtenbach. "Japan starts up offshore wind farm near Fukushima" The Sydney Morning Herald, 12 November 2013. Accessed: 11 November 2013.
  90. ↑ "Japan: Experimental Offshore Floating Wind Farm Project" OffshoreWind, 11 October 2013. Accessed: 12 October 2013.
  91. ↑ Jamie D. (2009-06-11). "N.J. must make wind farm permitting process as quick and easy as possible | Commentary | NewJerseyNewsroom.com - Your State. Your News". NewJerseyNewsroom.com. Retrieved 2013-07-06.
  92. ↑ Archived August 28, 2009, at the Wayback Machine.
  93. ↑ Streamline Renewable Energy Policy and make Australia a World Leader Energy Matters, 11 August 2010. Retrieved: 6 November 2010.
  94. ↑ "Nearshore wind turbines in Denmark" (in Danish). Danish Energy Agency, June 2012. Retrieved: 26 June 2012.
  95. ↑ "Smart from the Start" Bureau of Ocean Energy Management. Accessed: 20 November 2013.
  96. ↑ Accommodation Platform Archived July 19, 2011, at the Wayback Machine. DONG Energy, February 2010. Retrieved: 22 November 2010.
  97. ↑ Bjørn Godske. "Dong bruger supertele til vingeinspektion". Ingeniøren. Retrieved 5 June 2016.
  98. ↑ "3 Ways to Inspect a Blade". E.ON energized. Retrieved 5 June 2016.
  99. 1 2 "Tethys".
  100. ↑ "Tethys".
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