Over the last 30 years, wind turbines have become the second most important source of renewable energy in Europe. Denmark, Germany and Spain have been the leading countries driving the development, despite considerable public opposition.
The development has been marked by:
- a trend towards bigger turbines, from 0.3 MW in the early years to a standard size of 2.5 MW today, the biggest ones reaching 5-6 MW;
- declining generation costs, due to large-scale production and deployment;
- the planning of off-shore wind parks in the North Sea and the Baltic;
- the entry of big industrial players like Siemens and GE into an industry that had been in the hands of specialised medium-size manufacturers.
As a result of these developments more than one third of the newly installed power capacities in the EU are now wind turbines! Without mandatory buying rules for utilities and generous feed-in tariffs charged to electricity consumers the fast development of wind energy would have been impossible. But as generating costs will decline further, while fossil energy continues its upward price trend cost-parity with coal- or nuclear-generated electricity should be achievable towards the end of the decade. Indeed, the wind industry aims at making wind power the most competitive form of electricity by 2020 for land-based installations and 2030 for off-shore wind parks. These ambitious, but feasible targets are a precondition for the progressive phasing out of fossil-generated electricity.
For 2050, the industry targets a capacity of 600 GW installed wind power turbines, most of them land-based, compared to 84 in 2010, which should be able to supply 50 percent of the European electricity consumption. These objectives are in line with the road map towards a low-carbon economy presented by the European Commission March 8th. But does Europe have enough land and sea areas with constant wind to increase its wind-generated electricity seven-fold? And will it have enough facilities – in Scandinavia, the Alps or underground caves- to store electricity in the form of water or gas to bridge over any lull periods? These are the critical questions to which the industry and policy makers will have to give satisfactory answers.
One answer should come from even bigger and more efficient wind turbines. The most advanced machines presently under development will be real “power houses” with towers of 150 metre ( a quarter of the world’s tallest buildings) and rotor blades of 250 metre width, capable of generating 20 MW, more then three times the capacity of today’s biggest turbines. These turbines, which might come to the market by 2020, have four important advantages:
- They produce substantially more electricity per square km.
- They generate power even under feeble wind conditions: towers of 140 metre height producing roughly 50 percent more electricity than those 90 metre high.
- They are less noisy because higher and farther away from residential areas.
- They can easily be deployed above forest areas.
The second answer must come from the rapid extension of a European-wide grid, which will allow to compensate lull regions with those benefiting from strong winds at any moment of the year and also make up for the absence of solar electricity during night and cast-over skies.
The third answer has to come from much bigger storage capacities.
The last answer must come from sustained policy support. EU policy makers should rapidly fix targets for the share of renewable energies in electricity consumption by 2030 and continue subsidising research and crucial high-tension links.
But there remains another even more critical question to be answered: Is a 50 per cent share of wind in Europe’s 2050 electricity supply enough to turn Europe into a zero fossil and nuclear- free region? The answer should be “NO”. If Europe wants to be reach energy-autonomy wind should become its predominant source of energy by the middle of the century. That seems technically feasible thanks to ever bigger turbines and and off-share generation. Economically it is also possible as wind is set to become cheaper than either fossil or nuclear energy by the middle of the century latest.Author : Eberhard Rhein