OSLO, Norway In a novel use of clean energy, the world's most northerly town will soon be the first to get electricity from a sub-sea power station run on tidal currents tugged by the moon.
Gigantic forces in the oceans waves, currents, and tides have often proved too costly or awkward to harness, compared to wind or solar power, in global efforts to cut reliance on nuclear power or on fossil fuels blamed for global warming.
Starting in late November or early December, however, a tidal current will start turning the blades of a windmill-like turbine standing on the seabed near Kvalsund at the Arctic tip of Norway.
"We will be the first in the world to use tidal currents to generate electricity to be fed into the local grid," said Harald Johansen, managing director of Hammerfest Stroem.
Other unorthodox sub-sea experiments to generate power from tidal currents from Australia to Britain have not gotten to the stage of selling power. All the technologies mark a shift in traditional methods of exploiting the tide. Tides have previously been tapped for use in power plants in France, Canada, and Russia by building barrages to trap water in artificial lagoons at high tide. When the tide goes out, gravity sucks the water through turbines to generate electricity.
But giant damming projects are out of fashion because they can damage the ecology of rivers and coastlines. Seabed turbines, by contrast, are silent and invisible, and fish can swim around them without getting sliced up.
"Of all the renewable energy technologies, ocean energy is probably the one in the earliest stages," said Mark Hammonds at the International Energy Agency (IEA) in Paris. "Many projects have proved to be too costly."
Tidal power exploits the gravitational pull of the moon, and to a lesser extent the sun, on the oceans as the Earth spins. The seas rise and fall in a cycle of 12 hours and 25 minutes and can cause sweeping currents along the seabed at the same time, like the ones seen off the north Norway coast.