It was necessary to use variable speed to calculate loads on the company's first prototypes, he explains. But the converters needed for this technology are too expensive for commercial turbines, according to Bergqvist. Other technical components in the new edition will also be modified to make the turbine more suitable for series production.
Nordic Windpower will continue to use its flexible construction on the new turbine, where teeter hinge, shaft, yaw and tower are "soft," allowing the machine to "give" to the forces of turbulent conditions. This type of construction also makes a lighter turbine -- about 42 tonnes for the nacelle and 86 tonnes total, compared to 110 tonnes for similar megawatt machines, says Bergqvist. If the Nordic 1000 turbine can translate its lower weight into a lower price, it could certainly become competitive in a few years time, he adds.
After initial problems with the variable speed converter, the first Nordic 1000 produced 1953 MWh last year, compared to 1353 MWh for a Bonus 600 kW turbine at the same location, according to Nordic Windpower. A full year without difficulties with electronics should allow the machine to yield up to 2400 MWh. The company's 400 kW prototype running at Lyse on the west coast has not fared well, producing far less energy than its neighbour, a Bonus 450 kW unit.
The new Nordic 1000 will be developed together with Danish blade manufacturer LM Glasfiber A/S, supported financially from the EU Thermie research and development program. An additional model will be erected at an undecided location in 1999, the company says. In the long term Nordic Windpower will adapt the turbine for offshore installations, Bergqvist says.