Energy | 26. April 2010 | posted by Jan Oliver Löfken

Energy question of the week: Does the future of wind power lie in the open seas?

In January 2010, wind farms in Germany had a generating capacity of 25,777 megawatts. This means that almost eight percent of Germany's electricity requirement can be met in a climate-neutral way. However, since land areas exposed to strong winds are limited, both large and small-scale power-generating businesses are jostling for position out in the open sea. This poses a simple question: are offshore wind farms genuinely more efficient?

According to current projections, by the year 2030, German areas of the North and Baltic seas may be home to wind turbines generating approximately 25,000 megawatts. To date, the German Federal Maritime and Hydrographic Agency has approved 21 wind farms in the North Sea, and three in the Baltic. Valuable information on the anchoring, maintenance and operation of offshore wind turbines is currently being obtained from the 'alpha ventus' test unit, located roughly 45 kilometres north of the island of Borkum, anchored 30 metres deep.

Enough power for Europe – in theory

Despite the fact that the requirements governing foundations, operation during powerful storms and the adverse impact of salt water are all daunting factors, it would appear that the expenditure involved may prove to be money well spent. The European Environment Agency estimates in a recent survey that by 2030, the amount of energy generated by offshore wind farms could reach 3400 terawatt-hours per year. That corresponds about 80 percent of the predicted electricity consumption in EU countries (EU-27). This is made possible by the powerful and relatively constant winds out at sea, compared to those experienced in coastal regions.

Montage von 80 Windenergieanlagen des Typs Vestas V 80 vor der dänschen Nordseeküste. Bild: Vestas Central Europe, Bild oben: Bundesverband WindEnergie e.V.

Construction of 80 Vestas V80 wind turbines in the North Sea, off the Danish coast. Photo: Vestas Central Europe. Top photo: Bundesverband WindEnergie e.V. (German Wind Energy Association).

Apart from facing the technical challenges, operators need to be able to identify the best locations for their wind farms. An ideal site has constant wind conditions, relatively shallow water and a stable seabed, and is a short distance from the coast. As part of 'Windspeed' – a European research project coordinated by ECN, the Dutch energy research centre – DLR is involved in this important ‘inventory check’ of offshore generating potential.

The 'Windspeed' project analyses areas of realistic potential

"To enable better policy planning, our task is to seek out realistic options for offshore wind power," says Christoph Schillings from the DLR Institute of Technical Thermodynamics in Stuttgart. Along with his colleagues, Schillings is developing a software package to link, analyse and process the enormous volumes of available data into a usable format. "For these analyses, we run through both worst- and best-case scenarios," says Schillings. 'Windspeed' is scheduled to run until February 2011. By then, the politicians responsible for energy policy in Brussels, Berlin, London or Copenhagen will be able to evaluate the future potential of offshore wind power on the basis of reliable data.

Further information:

Good weather for the power plant? – First Symposium on Energy Meteorology (15 January 2009)

The DLR Energy question of the week in 'The future of energy' Year of Science

The Federal Ministry of Education and Research (BMBF) has given the Year of Science 2010 the motto 'The future of energy'. For this reason the science journalist Jan Oliver Löfken will this year answer a question on the subject of energy in his blog each week. Do you have a question about how our energy supply might look in the future? Or do you want to know, for example, how a wave power plant works and how it can efficiently generate electricity? Then send us your question by email. Science journalist Jan Oliver Löfken will investigate the answers and publish them each week in this blog.


About the author

Energy journalist Jan Oliver Löfken writes among other things, for the Technologie Review, Wissenschaft aktuell, Tagesspiegel, Berliner Zeitung and P.M. Magazin on issues involving energy research and industry. For DLR, he answered the Energy question of the week during the Year of Energy 2010. to authorpage