Wind Energy Regions: Denmark
20 years of experience at sea
In 1991, the first ever commercial offshore wind farm was installed in Vindeby, Denmark. It was ground-breaking at the time and heavily influenced offshore wind development. Due to Vindeby and the other projects that followed, the Danish Energy Authority published its Offshore Wind Turbine Action Plan in 1997. The action plan was then updated in 2007 to reassess selected sites and by describing high wind areas where up to 4,600 MW can be constructed, more than enough to supply Denmark’s entire domestic electricity consumption. This all contributed to making offshore wind a national agenda that pushed for the development of larger offshore wind farms that set new benchmarks. The most notable Danish wind farms are listed below in chronological order.
- Vindeby (1991): The wind farm consists of (11) 450kW stall controlled wind turbines, and is located approximately 2 km from the coastline. After being in operation for 20 years performance has been good, with an estimated 20% higher output than with comparable land sites. Along with an increased understanding of wind turbine design and operation, knowledge was gained in offshore wind conditions.
- Middelgrunden (2001): When commissioned it was the first offshore wind farm to consist of multi-megawatt wind turbines and was the largest offshore installation (40MW) at the time. Half of the turbines are owned by DONG (Denmark’s utility provider) and the other half is owned by a cooperative, which is a private partnership of local citizens that was formed in 1997. Actual wind turbine output is available to the public through the coop’s website along with any information regarding or related to the planning, construction and management of the wind farm so that others can learn directly from these experiences. Objectively, the wind farm seemed to be a difficult project. This was because of the site’s close proximity to Denmark’s capital, main airport and also to an important shipping lane. However due to the local ownership provided by the coop and excellent communication to the local community the wind farm proved to be a success.
- Horns Rev and Nysted/Rødsand (2002-2010): Horns Rev I (160MW) and Nysted (165MW) were established in 2002 and 2003 respectively. The slightly bigger Horns Rev II (209MW) and Rødsand II (207 MW), closely neighboring Nysted, were brought online in 2009 and 2010. These projects raised all known benchmarks within the field and greatly increased the understanding of the impact to the environment through heavy monitoring and by conducting several research projects.
- Anholt (2014): When Anholt’s 400MW comes online, 15% of the Danish electricity supply will be based on offshore wind. Following experience with previous tenders for offshore wind farms in Denmark, the Danish Energy Agency has adjusted the tendering procedure, which was used for the tenders for Nysted II and Horns Rev II. This means that this 400MW offshore wind farm will first undergo site development before being opened for public tenders.
- Kriegers Flak (TBA): The next large offshore wind farm, with tendering announced to start in the fall of 2011, will be the ground-breaking 600MW Kriegers Flak project. When completed, it will be the world’s first offshore wind farm with the grid connection replaced by a transmission line between Denmark and Germany, with a possibility of Sweden sharing it also. This project will showcase grid solutions needed to enable energy consumers in the several countries surrounding the Baltic Sea to tap into the vast energy resources of offshore wind.
Cost-cutting national R&D strategy
In 2010, the Danish Megavind technology platform presented a new vision and strategy for offshore wind. The aim is to drive down the cost of energy from offshore wind farms, and for offshore wind power to become fully competitive with newly built coal-fired power by 2020. Three main achievements are needed between 2010 and 2020. Firstly, newly built offshore wind farms must be able to produce roughly 25% more electricity per installed MW. Secondly, the costs per installed MW must be reduced by approximately 40%. And thirdly, the cost of operation and maintenance per installed MW must be reduced by about 50%. Cost reductions at this scale are also considered necessary to maintain public and political support for large-scale implementation of offshore wind in Europe and globally. Ultimately, delivering the solutions will maintain Denmark as a globally leading hub in wind power.
The Danish Energy Authority as a “one-stop shop”
The Danish Energy Authority is the authority responsible for the planning and erection of offshore wind turbines. In order to make preparation of new offshore wind turbine projects as simple as possible for project developers, the Danish Energy Authority has organized the overall official handling as a “one-stop shop”, which means that a project owner wishing to establish an offshore wind turbine project only has to deal with one body – namely the Danish Energy Authority – to obtain all the necessary approvals and licenses. As a one-stop shop, the Danish Energy Authority involves other relevant authorities such as the Agency for Spatial and Environmental Planning, the Danish Maritime Authority, the Danish Maritime Safety Administration, Danish Civil Aviation Administration, the Heritage Agency of Denmark, Danish Defense, etc. The Danish Energy Authority also arranges consultation with the relevant stakeholders and issues all the necessary approvals and licenses. In comparison with the official administration of offshore wind farms in other countries, the Danish model has provided a quick, cost-effective process to the benefit of operating economy in the individual projects and the development of offshore wind turbines as a whole.
Mapping of future sites for offshore wind farms
In order to ensure that the future development of offshore wind turbines does not clash with other major public interests and that the development is carried out with the most appropriate socio economic prioritization, the Danish Energy Authority, in conjunction with the other relevant authorities, has mapped the most suitable sites for future offshore wind farms. This mapping is a dynamic process because the framework conditions for developing offshore wind farms are continually changing. In 2007 the Danish Energy Authority published a technical mapping report designating 23 suitable sites, each with space for around 200MW. These possible offshore wind farms could achieve a total installed output of 4,600MW, and with average wind speeds of around 10 meters per second they could produce around 18 TW h annually, equivalent to more than half of current Danish electricity consumption. The sites are prioritized according to public interests such as regard for grid transmission, navigation, nature, landscape, raw material extraction, and the anticipated cost of establishing and operating the offshore wind farms. The cross-ministry committee work has placed its emphasis on a planned and coordinated development of offshore wind farms and the transmission grid, and the chosen sites have been submitted to a strategic environmental assessment in order to minimize conflicts with environmental and natural interests. Through its Offshore Wind Turbine Action Plan of September 2008 the Danish Energy Authority updated the mapping in light of the Energy Policy Agreement of 21 February 2008. The good wind conditions at the chosen sites allow the offshore wind farms to produce around 4,000 full-load hours a year. With sea depths of 10-35 meters and a distance to the coast of 22-45 kilometers, a balance has been struck between economic considerations and the visual impact on land.
As European electricity markets are gradually liberalized and become better interconnected, it will become increasingly attractive to harvest the offshore wind resource in Danish waters to supply electricity consumers elsewhere in Europe and to gradually substitute fossil fuels used also for transport and heating purposes.