Though most offshore wind turbines are doing quite well in the European Union, UK and in the German/Danish North Sea, still many power majors are hesitant to invest in offshore wind power. Setting the turbines out into the sea can solve land acquisition problems to an extent but accessing the turbines for maintenance, replacing key components and bringing in cranes for operations are some of the major drawbacks.
Despite this lukewarm response, GE and Göteborg Energi have recently started installing the first 4.1-113 offshore turbine rated at 4 MW in the Gothenburg harbor in Sweden. The two companies announced this at the European Wind Energy Association’s EWEA Offshore 2011 in Amsterdam.
First commercial application
This project marks the first commercial application of GE’s 4.1-113 technology, introduced in March this year at EWEA’s Brussels conference. The new turbine is expected to produce enough energy to supply 3,000 Swedish homes per year and reduces 15,000 tons of Co2 emissions, which is equivalent to the emissions of 7,500 cars per year.
The four megawatt-class wind turbine is designed to bring a new level of reliability to the offshore wind industry. Jonas Cognell, director of Renewable Electricity at Göteborg Energi said the project was a milestone in achieving the goal to produce more green energy for the people of Gothenburg. He said, “The wind turbine could not be placed any better: while it is located onshore, which makes it easily accessible, it is right at the water front and exposed to offshore weather conditions.”
Direct-drive technology
GE’s 4.1-113 is intended specifically for the offshore environment, with reliability and availability as the primary design drivers. The 4.1-113 blade design is optimized to maximize energy capture at sites suitable for monopile applications.
With fewer moving parts, the direct-drive technology focuses on keeping the turbines operating reliably at sea. It provides a simple, reliable design with built-in redundancy and partial operation for major components, and eliminates costly gearbox parts and lowers operating expenses.
The turbine is in Risholmsvägen, an area located at the harbour entrance and the door to Sweden, well-situated from a logistical point of view. With the installation planned to be completed by mid-December, and connection to the grid planned for the end of the year, we can expect the offshore project to move forward at a rapid pace. But whether other major players around the world will take cue from GE and Göteborg Energi, and invest in offshore projects still remains a big question.
