Wind energy is doubling every three years (roughly), according to the World Wind Energy Association (WWEA)

By Aurelia End (AFP) 

  HUSUM, Germany — The world's leading wind energy trade fair opened on Germany's windswept North Sea coast Tuesday, with close to 1,000 exhibitors from some 70 countries displaying the industry's growth.

The four-day event in Husum in northern Germany, expected to draw 30,000 visitors, had just 743 firms showing off their wares last time it was held two years ago, and the exhibition space has been increased by 40 percent.

The sharp rise reflects the rude good health of the industry, with the amount of electricity produced by wind energy roughly doubling every three years, according to the World Wind Energy Association (WWEA).

Major factors have been new markets such as China and Brazil opening up as countries worldwide seek to slash carbon dioxide emissions produced by conventional sources of power like coal.

But although the sector's prospects are seen as staying healthy medium term, the number of wind turbines installed will decline this year due largely to a slowdown in the United States, according to the German Wind Energy Institute (DEWI).

And long term, in countries such as Germany, which has been one of the most active in developing wind energy with 21,000 turbines already in place, something of a slowdown is inevitable due simply to a lack of space.

Operators are doing what they can by modernising -- "repowering" as it is known in the trade -- and by expanding existing wind parks, but this can also run into opposition from locals who find them an eyesore.

The real answer, experts say, is to place large numbers of wind turbines offshore where they can be powered by sea winds well away from humans, something which is a big talking point among delegates in Husum this year.

But building machines as tall as cathedrals "in depths of 40 metres (130 feet) ... is a big question mark," Lutz Mez, professor at Berlin's Free University, told AFP.

Transmitting the power to where it needs to be is also problematic and environmentalists, while supporting the development of alternative energies, worry about the impact on marine and coastal wildlife.

Nowhere is the dilemma clearer than in Germany, which has ambitious plans for more than 80 offshore wind parks. Only one -- a pilot project -- is up and running.

Husum's host country is also under fire from renewable energy firms because of plans by Chancellor Angela Merkel's government to postpone the date when Europe's biggest economy abandons nuclear power.

Merkel wants to extend the lifetime of Germany's 17 nuclear reactors by an average of 12 years beyond a previously scheduled shutdown of around 2020 as a "bridge" until renewable sources of energy such as wind and solar suffice.

"The government's plans are torpedoing the development of renewable energy," said Hermann Albers, head of the German Wind Energy Association (BWE).

Anti-nuclear protesters have vowed further demonstrations in the coming weeks after tens of thousands rallied in Berlin on Saturday, while opposition lawmakers have said they want a referendum on the issue.