VIDEO: Offshore turbine achieves reliability run with 99.05 per cent availability

Paul Boughton

GE says its 4.1-113 offshore wind turbine, nicknamed Big Glenn and located in Sweden’s Gothenburg harbour, passed its initial trial run. This announcement was made at the European Wind Energy Association’s EWEA 2012 in Copenhagen.

Beginning February 29, the trial lasted 200 hours. GE’s first direct-drive offshore wind turbine passed this reliability run on its first attempt with 99.05 per cent availability. Wind speed varied during the trial run from zero to rated wind, resulting in a capacity factor of 35.3 per cent.

“The variation in wind speed gives the team confidence that the turbine performs reliably under all wind conditions,” says Vincent Schellings, Offshore Product Manager for GE Energy. “Now we will begin validating the design and obtain initial results before summer. Our initial focus will be on the power curve and loads validation as evidence that our simulations meet the measurements of the two performance characteristics that matter most to our customers.”

The test run was successfully completed in March. “We are very proud to support our city and our country towards the goal of producing more green energy. Due to great teamwork of our team together with GE and Chalmers University we can celebrate this important milestone”, said Jonas Cognell, director of Renewable Electricity at Göteborg Energi.

GE’s 4.1-113 is intended specifically for the offshore environment, with reliability and availability as the primary design drivers and builds on the experience with over 17,500 units globally.

With fewer moving parts, the direct-drive technology provides a simple, reliable design with built-in redundancy and partial operation for major components, all focused on keeping turbines operating reliably at sea. The direct-drive technology eliminates costly gearbox parts and lowers operating expenses.

The 4.1-113 blade design is optimized to maximize energy capture at sites suitable for monopile applications. Based on five years of operating history of the installed fleet of GE 3.5 MW turbines, the platform is well proven.

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