Environmental Technology, News

Wind power – the push offshore

Norway’s oil adventure began in the 1960s with the discovery of the Ekofisk field in the North Sea. Four decades later, the country is preparing to harvest its next great offshore energy resource: wind. Estimates put the theoretical potential for...

Norway’s first wind power farm dates back to the 1991 with the development of Husfjellet in Vikna by Nord-Trøndelag Elektrisitetsverk. Before that it was just single turbines in different locations around the country. Husfjellet was built before the legal framework for licensing was established by the Energy Act. The first to be built with a concession was Fred Olsen Renewables’ Fjeldskår wind farm at Lindesnes in 1998.

Since then, the Norwegian Water Resources and Energy Directorate (NVE) has granted licenses to 30 projects, 420 MW of which are in operation and 1,300 MW yet to be built, while 34 projects (400 MW) are on hold. The bulk of these projects are onshore. The largest one so far is Statkraft’s Smøla wind farm in Møre and Romsdal, Europe’s largest land-based wind generating facility. Here 68 turbines produce 0.45 TWh of electricity, enough to power 22,500 Norwegian households.

However, an increasing number of applications are being made for offshore wind projects, both fixed sea bottom projects in shallow waters and fully floating windmills for Norway’s deeper seas. There are currently 19 notifications for offshore wind parks in Norway, seven of which are floating installations. In addition, Norwegian companies are taking their technology offshore to other coasts, like StatoilHydro and Statkraft’s recently announced 10BNOK project to develop the Sheringham Shoal Offshore Wind Farm near Norfolk.

With a total of 68 wind turbines, the Smøla  Wind Farm is Europe’s largest land-based  wind generating facility, producing an annual 450 GWh of electricity  © Statkraft

World’s First Full-scale Offshore Windmill

The leading project offshore Norway so far has been StatoilHydro’s Hywind. The Norwegian oil company has used its experience from managing large deepwater petroleum fields towards developing the world’s first full-scale floating windmill. The company will place a 2.3MW windmill 10 kilometres from the coast of Karmøy, north of Stavanger, this summer for a two-year test period.

SWAY, a Norwegian floating wind turbine company owned by Inocean, Statoil, NorWind, Lyse and Stakraft, intends to locate its first floating turbine in the waters outside Karmøy in Rogaland. There it will be connected to a planned testing centre for marine renewable energy for two years.

The NVE is currently processing the application for Testområde Stadt. Vestavind Kraft plans to test a floating wind turbine in three stages offshore Selje and Vågsøy so that it can gradually expose it to harsher winds and seas in three different locations. The turbines will generate less than 10 MW of power.

All three of these are relatively small and pilot phase only. The hope is that testing will provide the basis for building bigger wind turbines and for deeper water depths. There are other companies, such as Fred Olsen Renewables, Ocean Wind, Vestavind Kraft and Lyse, which are planning floating windmill projects offshore. However, they are on hold until a licensing policy can be sorted out.

Part of the rationale for going farther offshore is the more efficient wind power production due to higher average wind speed. Another is the greater acreage to choose from and remoteness, which generally leads to less conflict. New technology could even open up at some point for integrating wind power with existing gas and diesel generators on offshore oil and gas platforms.

Hywind tow: Floating windmill at sea in deep water. 
© Kim Laland/StatoilHydro

New Licensing Policy & Technology

However, there are still many hurdles. Offshore wind parks could come into conflict with the fishing and shipping industries. They are more expensive to build and maintain. There is an insufficient electricity grid in Norway. Plus, there are a lack of cost incentives and undeveloped legal framework for offshore licensing.

“There are several technical and monetary challenges that must be dealt with before the potential for wind energy generation in the North Sea can be realized,” said Gudmund Synnevåg Sydness, consultant in NVE’s energy concession department. However, he added, “The wind resource suggests that Norway has a great potential for building wind farms offshore.”

Norway is actively working to sort out these challenges. The government is currently drafting a new concession policy that could end up resembling the licensing rounds for offshore petroleum blocks. It is also working on determining the relevant licensing authority.

Under the Energy Act of 1990, the NVE can currently grant licenses to onshore and offshore wind power plants within the sea boundary (i.e. located in the waters between the mainland and nearby islands) with higher installed capacity than 10 MW. In addition, projects bigger than 10 MW, both onshore and offshore within the sea boundary, require an environmental impact assessment.

Many Norwegian companies are actively involved in bringing the cost down by developing new offshore technology. WindSea, a joint enterprise between Statkraft, NLI Innovation and FORCE Technology, has developed a triple turbine based on three turbines on each corner of a triangle-shaped, floating platform. This makes it more stable, simplifies access for repairs, and is easier to install and move.

Another example is Stavanger-based AngleWind, which has developed a smaller gearbox for wind turbines that has less revolutions and less parts. In Bergen, a company called Owec Tower has developed a jacket quattropod that is low weight, yet able to support heavy turbines and can be installed on the seabed in even demanding soil conditions.

Norway’s research community is also committed to finding new technological solutions. This February, the Norwegian Research Council dedicated two of its eight centres for environmental-friendly energy research (CEER) to offshore wind power. The Christian Michaelsen Research in Bergen will host the Norwegian Centre for Offshore Wind (NORCOWE) while SINTEF will host the Research Centre for Offshore Wind Technology in Trondheim.