With new projects currently under construction in the UK and the Netherlands, and serious advances taking place in many other countries, is offshore wind development finally beginning in earnest? Alasdair Cameron reports.
Since the earliest days of the wind industry, offshore has been seen as the logical ‘next step’ in the progression of wind power. Winds at sea are stronger and more consistent than those on land (load factors average up to 40%), and, particularly in the densely populated European and East Asian countries, the sea offers a great deal more space, allowing scope to construct vast gigawatt-scale developments which may not be acceptable on land. Yet despite the obvious advantages of going offshore, the industry has grown more slowly than expected, thanks to a combination of factors, including the difficulties of working at sea, high turbine prices (caused by the boom in onshore wind), lack of cohesive government support and the high costs of grid connection. At last, however, the pieces seem to be in place in a number of countries, and the next few years should see the rapid expansion of this exciting field.
Growth on all fronts
Since the first offshore wind farm was constructed in 1991, a total of 770 MW of offshore wind has been installed in five countries – Sweden, Denmark, the Republic of Ireland, the Netherlands and the United Kingdom. Most of these have to some extent been demonstration projects, as developers and manufacturers test their equipment and installation techniques. Now the next stage is underway, with plans for thousands of megawatts of commercial offshore wind.
Installing monopiles at the 90 MW Burbo Bank offshore wind farm near Liverpool in the UK dong energy a/s
While the North Sea region is undoubtedly the centre for offshore wind activity, projects are now being considered all over the world.
Despite its small size, Denmark has been the undisputed trailblazer of both on- and offshore wind, installing the world’s first offshore wind farm at Vindeby in 1991. Ten years later it led the way again, installing the first large offshore wind farms, beginning with the 40 MW Middelgrunden development near Copenhagen, and then the two 160 MW wind farms at Horns Rev and Nysted. Despite some initial problems at Horns Rev, these wind farms have generally been a success and Denmark’s offshore wind capacity stands at around 380 MW – the highest in the world, and by far the highest per capita.
Now, after a gap of several years, plans are yet again underway to increase Denmark’s offshore wind capacity with Horns Rev II, a proposed 200 MW extension to the existing wind farm.
In addition to its own offshore wind farms, Denmark is host to a number of leading companies in the offshore arena, including Vestas, the world’s leading manufacturer of wind turbines for on- and offshore use. To date, Vestas has installed almost all the offshore turbines currently in use and has positioned itself well to maintain its lead in the sector. Before it was taken over by Siemens, Denmark was also the base for Bonus, another manufacturer of turbines for offshore use. On the construction front, Denmark is home to A2SEA, a specialist company that uses purpose built vessels, the MV Sea Installer and MV Sea Energy to install turbines for offshore wind farms.
Along with Denmark, the United Kingdom is the country which has most fully embraced offshore wind, and which, through its Round 1 and 2 projects, looks set to be the key market for the next ten years (see below). The extension of the Renewable Obligation (the UK’s renewables support scheme, which sets the level of renewables in the electricity system) to 15% by 2015 has helped to reassure the industry that long-term support will be there, while the government has recently indicated that it wishes to ‘band’ the RO to increase support for less mature forms of renewable energy.
Speaking about the British government’s plans, the British Wind Energy Association’s Director of Policy Gordon Edge said: ‘The whole banding debate is the government trying to get offshore wind away.’ He expects to see the banding system structured to reflect this, with offshore wind earning more than one Renewable Obligation Certificate (ROC) per MWh generated. ‘1.4 ROCs per MWh is the bare minimum’, he says.
A foundation for an offshore turbine at the Beatrice project in Scotland. The next few years should see impressive growth in the offshore industry, particularly in the UK alasdair cameron
Indeed offshore wind energy in the UK is seeing a surge in activity, partially in anticipation of these new support measures. Gordon Edge: ‘We are seeing a bit of a step change with the Round 1 coming on and Round 2 getting consent. After five years of one project a year, 2008 should see building on three projects.’
Despite these encouraging signs, there are still serious concerns over the stability and extent of government support, with some calling for a more clear and concise system of subsidy. Recently, a group of senior economists called on the UK government to abandon the RO and replace it with a German-style feed-in tariff, claiming that the current system would not allow the UK to maximize its renewables potential. Indeed, to date, all the offshore wind farms built in the UK have needed additional support in the form of £10 million (€15 million) capital grants to make them viable, a trend that is unlikely to continue into the future.
However the British Wind Energy Association (BWEA) has reiterated its support for the RO, and warned the UK government that unnecessary meddling could harm the emerging industry. While it supports the concept of increased support for offshore wind, the BWEA fears that this may mean resources being diverted from onshore wind, which is naturally the mainstay of its members’ business. Critics have pointed out that onshore wind operators are making huge profits, since the RO system favours the cheapest and most competitive technologies – a claim rejected by Gordon Edge: ‘Let’s look at the figures. Wind only receives a sixth of the RO money, most goes to landfill gas which is cheaper than wind.’
It does remain true though that the global boom in wind power has placed a strain on the supply of turbines, leading risk-averse manufacturers to shy away from offshore developments. The hope must be that as the industry settles into a more stable and sustainable growth pattern that this will become less of a problem.Rounds 1 and 2
In order to regulate the development of offshore wind, the Crown Office – the body which controls the coastal waters around the UK – conducted two rounds of offshore licensing. Round 1 invited applications to develop wind farms consisting of up to 30 turbines. Thirteen licences were awarded, and, if all are completed, these will have a combined capacity of around 1500 MW. So far four of these projects, totalling 300 MW have been finished – at Scroby Sands, North Hoyle, Kentish Flats and Barrow. A fifth, Burbo Bank, is in the final stages of construction, while building on three others (Solway Firth, Lynn and Inner Dowsing) should begin in 2007-2008. By 2009, around 900 MW of Round 1 projects could be complete (Table 1), potentially including the projects at Rhyl Flats and Gunfleet Sands.
Round 2 of the Crown Estate’s licensing procedure threw the door open to wind farms of unlimited size, with 15 projects given initial approval, totalling 7169 MW (capable of providing around 7% of the UK’s electricity supply). Some of these projects, such as Triton Knoll and the London Array are very large indeed, more than 1 GW in size. Most of the Round 2 projects are clustered into three main areas, the Thames Estuary, the Greater Wash (the area north of East Anglia on the east coast of England) and the North West of England (Table 2).
Installing turbines at the 108 MW Egmond an Zee wind farm in the Netherlands shell / nuon
Although licences have been awarded, each of these projects must still apply for specific approval. In late 2006, the British government granted final consent for the offshore portions of the first two Round 2 wind farms – the 300 MW Thanet and 1000 MW London Array developments. Following on from these initial consents, in February 2007, a third Round 2 wind farm, the 500 MW Greater Gabbard project, was also granted consent. Of these, Thanet looks like it will be finished first, as the developer Warwick Energy is indicating that it will fast-track construction for a 2008 or 2009 completion. Indeed, it has already awarded key supply and construction contracts and begun onshore cabling work. Greater Gabbard could be next, with the developer aiming to start construction in 2009. The London Array, on the other hand, still requires planning permission for its onshore works – to be decided at an upcoming public enquiry. If successful, building work on the project can begin, and the wind farm should be completed in 2010-2011, just in time for the London Olympics.
Speaking at the time of the London Array announcement, Maria McCaffery, the Chief Executive of the BWEA, said: ‘The significance of these decisions is far greater than the projects themselves, although they will bring many notable benefits to the UK in terms of clean carbon-free generation. Far more important is the clear signal from the UK to the rest of the world that this country is open for business for offshore wind, and we look forward to more consents in the near future.’
Indeed, this has begun to happen, and government support has already encouraged the developers of other Round 2 wind farms with several looking to apply for consent in 2007. Centrica, one of the UK’s largest utilities, will seek final permission for three wind farms, Docking Shoal, Race Bank and Lincs, representing 1250 MW of capacity. Meanwhile DONG, a Danish utility, is expected to have secured consent for its 450 MW Walney Offshore wind farm by the end of the year, while RWE npower renewables has just recently applied for detailed consent for its 750 MW Gwynt y Mor wind farm off the coast of Wales. Assuming that permission is granted, initial work on both these developments could begin as early as 2008.Other UK developments
In addition to the Round 1 and 2 projects, a number of innovative offshore schemes were also granted permission by the British government outside the normal licensing rounds. These include the 10 MW Beatrice demonstrator project near Aberdeen, and Eclipse Energy’s Ormonde wind-gas hybrid development. The Beatrice project is particularly interesting as it takes place in relatively deep water (40-44 metres) and employs the largest wind turbines used offshore to date (5 MW REpower turbines). Although the project has experienced some installation delays due to poor weather conditions, the first of the two turbines is up and running, and the second is due to be installed in the first half of 2007. If successful, the developers Scottish & Southern Energy hope to expand the wind farm to a total capacity of 1000 MW, making it one of the largest wind farms in the world, capable of supplying electricity for the entire city of Aberdeen (for more information on the Beatrice project see article in Renewable Energy World Nov-Dec 2006).
The Ormonde project on the other hand, will be located in the Irish Sea and combine offshore wind power generation with natural gas extraction. In February 2007, the developers announced that they had received final consent to proceed with the wind farm, following and in-depth environmental impact assessment. The project will consist of 30 wind turbines of around 3.6 MW each, arranged next to a marginal gas field. The idea is to install a temporary rig which will extract the gas, and share the cabling and transmission structure of the wind farm. After 6 or 7 years, once the gas is depleted, the rig can be moved on to another site and the process repeated, leaving the wind farm in place. In effect the gas will be subsidizing the wind farm. Interestingly this project has so far received no capital grants, emphasizing its new business model. Assuming all goes according to plan, construction should begin in 2009, with commissioning in 2010.
The MV Resolution getting ready to install turbines for the Barrow offshore wind farm in the UK centrica
But by far the grandest scheme proposed for UK waters is the first stage of the pan-European Supergrid, a concept developed by Irish company Airtricity, which would see an offshore grid linking wind farms all the way down the west coast of Europe, from the North Sea to Portugal. The energy provided by the grid would be traded freely across Europe and provide a means of harnessing the weather systems which move in from the Atlantic and sweep across the continent. While this project remains a long way off, Airtricity is currently in negotiations to secure €20 billion in funding to develop a 10,000 MW wind farm in waters off the UK coast. In the long term it is hoped that this, and other projects, could link up to provide truly reliable and large-scale renewable electricity generation. Interestingly, in an indication of how seriously this project is now being taken, at the beginning of 2007 the European Commission appointed what has been described as an ‘offshore grid tsar’ to oversee and manage the development of international offshore grids for wind energy.
Like Denmark, the Netherlands was one of the pioneers of offshore wind, with several small-scale projects being developed in the early 1990s. Now, after a lull of ten years, the Netherlands is experiencing a new phase of offshore wind development, with one large wind farm recently completed and foundation installation taking place on another.
Developed by Nuon and Shell, and completed in late 2006, the 108 MW Egmond an Zee was the Netherlands’ first large offshore wind farm, and its first to use multi-megawatt turbines. In addition to Egmond an Zee, work is already underway on the 120 MW QP-7 offshore wind farm, which is being built by Econcern and Eneco, and due to be complete by the end of 2007.
A third, similar sized project in the pipeline is the 100 MW Near Shore Windfarm (NSW) which has been conceived by Nuon and Shell as a 20-year demonstration facility to test and measure the long-term impacts and needs of an offshore wind farm.
Finally, Aitricity was recently awarded a site by the Dutch government for a proposed 248 MW wind farm at West Rijn. The next stage will see a public consultation and environmental impact assessment.
Looking to the future, the Dutch government estimates that there is space for up to 6000 MW of offshore wind, with around 3000-5000 MW under serious consideration.
Led by Econcern, a locally based developer, Belgium is gearing up to make its first steps into offshore wind with the proposed 330 MW Bligh Bank offshore wind farm. Consenting and planning procedures are currently underway, with the developers estimating that if all goes well, construction could begin in 2009.
In addition to its Belgian and Dutch developments, Econcern is also working on the Sheringham Shoal offshore wind farm in the UK, one of that country’s Round 2 projects.
Despite its hugely successful onshore wind industry, offshore development in Germany has been slow, with only one turbine installed to date. One of the reasons for this delay, aside from the relative lack of space offshore (due to Germany’s short coastline), has been the feeling among developers that in order for German offshore wind farms to become profitable, larger turbines are necessary, typically over 5 MW. This is largely because most German offshore wind farms will need to built in deeper water as almost the entire nearshore area is environmentally protected. To this end, most of the advances in offshore wind in Germany have been on the technological front, with the country having a clear lead in the manufacture and supply of large turbines.
In 2006 however, the German offshore wind industry received a major boost when the government passed a law which placed the costs for the grid connection of offshore wind farms onto the grid operators, as is the case will all other sources of power. This is very important as grid connection can add as much as 30% to the cost of an offshore wind farm. Suddenly German offshore wind has become profitable and developments can be expected, with some estimates suggesting that up to 3000 MW of offshore wind could be in place by 2012.
A wind-data mast deployed at the site of the Lillgrund wind farm in the Baltic sea off Sweden risø national laboratory
In the immediate future though, German offshore development is likely to be confined to the 60 MW Borkum West demonstration programme. Funded by the German government along with RWE, Vattenfall and E.ON, this project is designed to test the performance of twelve different 5 MW+ turbines – from REpower, Multibrid and Enercon.
Possibly the first of the large projects to come to fruition will be the 300 MW Butendiek wind farm, being developed by Airtricity. This site’s relative proximity to shore and shallow water make it one of the most straightforward of the German offshore ventures. Another project being planned is the 80 turbine Enova project, being developed by E.ON.
Sweden built its first offshore wind farm in 1997, with two others following in 2001. These developments were small however, with a total capacity of only 23 MW. Sweden’s largest project to date will be the 48 turbine, 108 MW Lillgrund project in the Baltic Sea, which is being developed by Vattenfall and will be completed in 2007. Lillgrund is just the start however, and Vattenfall has ambitious plans for much larger projects in the future, including a 540-600 MW development as part of the multinational Kriegers Flak offshore wind farm. The company estimates that work on Kriegers Flak could begin in 2008-2009, and be finished by 2011.
Like the UK, Ireland has a tremendous wind resource and great potential for the development of offshore wind. Back in 2000, six licences were awarded to a variety of consortia to investigate the possibility of developing offshore wind farms of Ireland’s east coast. So far however, development has been limited to a single project – the 25 MW Arklow Bank wind farm, built and supplied by GE to demonstrate its new 3.6 MW offshore turbine. Stage 2 of Arklow Bank is currently being developed by Airtricity and Acciona Energy and is likely to have a total capacity of around 500 MW. Construction has not yet started and is not expected to be complete until after 2010.
While Arklow Bank is the only Irish offshore wind project to see any real progress, others, such as the 250 MW Kish Banks project are beginning to see increased interest and activity (for more information on the Irish renewables industry, see article on page 111).
With its huge coastal territories and excellent wind resources, the United States has vast potential for offshore wind. Indeed, a recent report released by the University of Delaware has concluded that the accessible offshore wind resource of the mid-Atlantic bight, stretching from Cape Cod, MA, to Cape Hatteras, NY, could be 330 GW, sufficient to supply all the energy needs of the nine mid-Atlantic states, with enough left over to provide for a 50% future increase in energy demands.
Sadly, despite this great potential, no projects have been built and offshore wind in the US is still in its early stages. There are, however, several projects being proposed.
Perhaps the most well known of the United States’ proposed offshore wind farms is the beleaguered Cape Wind project in Nantucket Sound, famous as much for its high-profile opponents (which have included Senator Edward Kennedy) as for anything else. While a number of obstacles have been thrown in the way of this development, the project is still inching forward, with an Environmental Impact Assessment currently being conducted by a total of 17 federal and state agencies. So far the draft assessment has been positive, although the developers are still awaiting a final decision.
If it finally gets built, the plan is for a 420 MW wind farm, consisting of 130 turbines. Given the strong offshore winds, the developers estimate that the wind farm would be able to supply 75% of the Cape and Islands region’s electricity needs.
Also in the US Northeast, plans are underway to build a 140 MW offshore wind farm near Long Island. The project has been proposed by the Long Island Power Authority to help it meet its growing demand for energy and the consenting procedure is now underway. If successful the developers hope to begin construction in 2008. So far this project seems to have been spared the controversy surrounding Cape Wind, and has the backing of many of the local residents and the Governor of New York.
Further south, in the Gulf of Mexico, applications have been submitted for a 150 MW offshore wind farm at Galveston Island in Texas. So far the plans involve the deployment of 50 turbines of 3 MW each. The project is being developed by a Louisiana-based company called Wind Energy Systems Technologies and its subsidiary Galveston Offshore Wind LLC.
Still in Texas, work is underway to build a larger 250-500 MW offshore wind farm at Baffin Bay. The project received a boost when the developer Superior Renewable Energy was granted a lease in 2006 by the Texas General Land Office to develop 39,000 acres (15,780 hectares) of seabed near Padre Island, to the south of Corpus Christi.
As China’s breakneck economic development continues, its authorities are investing in new energy generating capacity (including wind power) at an incredible rate. Indeed, in 2006, China grew to become the world’s fifth-largest wind market, installing 1367 MW of new capacity. While this may be small in comparison to the 100 GW of new conventional power that it installed in the same period, it is enough to make China one of the most important players in the international wind industry.
Now China could be getting ready to expand into offshore wind, with plans being mooted for several developments. One of these could be a proposed 100 MW wind farm in the bay near Shanghai. This project demonstrates one of offshore wind’s main attractions for China – the ability to develop new generation next to the energy-hungry and densely populated eastern coast. At present, the imbalances in China’s energy supply and consumption (much energy is generated in the central and western areas, while the main demand is in the east) are placing great strains on the grid. Offshore wind could help to alleviate some of these problems, albeit at present on a very small scale.
The next wind farm which may be built is another 100 MW development, this time in Hong Kong. The project is being developed by Hong Kong Electric Holdings, but is unlikely to be built before 2012. Hong Kong is particularly keen to try and tackle its crippling air pollution and clean up its environmental image. Indeed in 2006, a high-profile investment house advised its clients to divest money in Hong Kong property and move it to other Asian markets such as Singapore, where pollution was less severe.
Finally, plans have been discussed for a third 100 MW offshore wind farm in Hebei province in the north of the country, and some reports suggest that this could be the country’s first offshore wind farm to be completed, with construction reportedly due to begin in 2007.Other developments
New offshore wind developments are continuously cropping up as more countries enter the market. In Canada, the 700 MW Great Lakes project on Lake Ontario could be the first inland offshore wind farm, while French group La Compagnie du Vent is proposing a 700 MW offshore wind farm for the English Channel. If successful, construction could begin by 2010.
The 60 MW offshore wind farm at Scroby Sands, UK powergen
Meanwhile, technological advances continue to be made on all fronts. In Norway, for example, offshore engineering company Hydro is working on developing floating turbines for deep offshore applications. If successful this could open up a huge area of the ocean to energy generation. This technology is being followed particularly closely in Japan, which has limited space for onshore development, and relatively deep coastal waters.
There is a sense of excitement and anticipation in the offshore wind industry. Few other forms of renewable energy offer the same potential for truly large-scale carbon-free generation, and while in the near future it will be a largely European affair, in the long term it will likely become a truly international effort.
Alasdair Cameron is Assistant Editor of Renewable Energy World