Swedish Old-Timer Gains Momentum

The Danish Momentum Gruppen has, in partnership with DEIF Wind Power Technology, repowered and recommissioned the five-turbine Bockstigen offshore wind farm in Sweden.

The project included replacing the nacelles, blades and control systems of the five 500kW WindWorld turbines installed in 1998 by newly refurbished parts from Vestas V47 660kW turbines.

DEIF delivered the control solution and technology, as well as an intelligent wind park control solution, while Danish WindTech supplied the mechanical parts to refurbish the turbines.

According to Momentum Gruppen, the towers, foundations and subsea cables passed an extensive durability test and are therefore reused.

The replacement is expected to extend the technical lifetime of the turbines to +15 years and more than double the production, from approximately 5.000MWh. to 11.000MWh, the company said.

“The partnership with DEIF Wind Power Technology has been very successful and DEIF retrofit specialists have been very supportive throughout the start-up phase to installation and commissioning of the wind park,” said Kim Madsen, CEO of Momentum Gruppen.

“DEIF has delivered the control solution for the 5 repowered V47 turbines and has contributed to a significant upgrade of the turbines. We see a potential for a strong future collaboration for repower projects of older turbines and the collaboration with DEIF indicates that they will be our most important collaboration partners for these projects.”

Installed 4km off the coast of the island of Gotland, the Bockstigen project is Sweden’s first offshore wind farm.