November 2, 2005
Sea-Based Windmills Could Blunt Eyesore Criticisms
By Alister Doyle, Environment Correspondent
OSLO -- Windmills floating on the high seas could produce electricity from 2007 in a scheme likely to please critics who reckon that land-based turbines are an eyesore, Norwegian energy group Norsk Hydro said on Wednesday.Out of sight over the horizon, parks of non-polluting windmills could eventually supply power to coastal cities or to offshore oil and gas platforms anywhere from the North Sea to the Gulf of Mexico.
Hydro said it aimed to go ahead with a project to build a prototype -- an upright steel and concrete tube about 200 meters (660 feet) high with 80 meters jutting above the water and rotor blades 60 meters long -- after successful laboratory tests.
Some nations have parks of windmills that stand in shallow waters offshore but none have windmills far from land.
"The results are promising," Alexandra Bech Gjoerv, head of New Energy at Hydro, told Reuters of a three-year research program. "We're very hopeful that we can be first in the world to set up a floating windmill at sea."
She said rivals in nations from Japan to the United States were also working on designing similar windmills.
Hydro, Norway's number two oil producer behind Statoil, hopes to deploy a prototype at sea in 2007, likely to cost about 150 million Norwegian crowns.
Norway is the world's third largest oil exporter after Saudi Arabia and Russia.
The floating windmills would be tethered at three points to the seabed to keep them stable. Bech Gjoerv said that there were likely to be fewer objections to windmills offshore.
"On land there are objections partly to visual pollution, partly problems with birds and other environmental issues like laying cables through the countryside," she said. Birds are sometimes killed by flying into windmill blades.
Bech Gjoerv said electricity from offshore windmills was likely to cost more than electricity from fossil fuels, nuclear or big hydropower plants. Maintenance costs could be higher.
WINDIER AT SEA
"Initially we want to compete with windmills on land. It's a lot more windy out at sea -- installation costs will be higher but the production will be higher," she said.
Each 5-megawatt windmill would be capable of generating about 22 gigawatt hours a year. That would be enough to supply electricity to about 1,000 typical Norwegian homes.
If the concept works, Hydro envisages parks of perhaps 200 windmills, in waters 200-700 meters deep.
"We're using a tested platform concept, windmill technology that's well known and an anchoring system that is known. It's a radical adaptation of the technology," Bech Gjoerv said.
Many countries are trying to shift to cleaner energies like wind or solar power to curb emissions of heat-trapping gases like carbon dioxide from fossil fuels burned in power stations, cars and factories.
The scientific panel that advises the United Nations says that rising temperatures could trigger more floods, storms, spread deserts and drive thousands of species to extinction.