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Ceremony Held to Mark the Launch of Verification Testing of World's First Digital Hydraulic Drive Train for Offshore Wind Turbines at Hunterston Test Centre in the UK


Tokyo, February 5, 2105 - On February 4 (London time) Mitsubishi Heavy Industries, Ltd. (MHI) have begun onshore verification testing of a large-scale (MWT167H/7.0) digital hydraulically driven offshore wind turbine at the Hunterston Test Centre1 in the United Kingdom. The wind turbine was developed with support from Japan's New Energy and Industrial Technology Development Organization (NEDO), the UK Department for Business, Innovation & Skills (BIS) and Innovate UK (TSB). Its operation at the Hunterston site is a world's first for a large-scale wind turbine with a hydraulic drive train controlled by Digital Displacement2.

MWT167H/7.0 at Hunterston test centre
A ceremony was held at the site to commemorate the event. Attendees included: Jim McPhillimy, Managing Director of SSE plc. (formerly Scottish and Southern Energy plc.), a leading utility provider that owns the test center; NEDO Executive Director Munehiko Tsuchiya; BIS Carolyn Campbell, Head of offshore wind industrial strategy, and TSB, David Hytch, Lead technologist offshore renewable. Representing MHI was Masafumi Wani, Chairman of Mitsubishi Heavy Industries Europe, Ltd.

The test turbine at Hunterston is a 7MW unit featuring a Digital Displacement2 controlled hydraulic drive train in its power transmission system. This technology was developed jointly by MHI and Artemis Intelligent Power, Ltd., a venture firm acquired by MHI in 2010, this acquisition brought in the Artemis's hydraulic Digital Displacement2 technology. Equipped with this system, the wind turbine converts wind energy by a combination of pumps and motors to produce a constant speed irrespective of the blade rotation speed, eliminating the need for a step-up gearbox, complex generator technology and power inverter.

The wind turbine was constructed at the site by assembling the nacelle and other core components transported to the UK from MHI's Yokohama Dockyard & Machinery Works (Kanazawa Plant) and European locations. The rotor blades are 81.6 meters (m) long, with a rotor diameter of 167m. Rotor hub height is approximately 110m, and overall tip height is close to 200m.

Based on the results of the onshore verification testing at Hunterston, MHI plans to install a second and similar hydraulically driven wind turbine during 2015 on a floating platform within a wind farm verification research project being implemented offshore from Fukushima Prefecture.

Subject to successful verification testing at Hunterston and Fukushima MHI intends to supply the new hydraulic drive train to MHI Vestas Offshore Wind A/S, a joint venture dedicated to offshore wind turbine market development with Vestas Wind Systems A/S of Denmark.

1 The Hunterston (Onshore) Test Centre, operated by SSE, is the UK's first officially authorized offshore wind turbine testing facility. Located in North Ayrshire, Scotland, A Siemens SWT-6.0-154 turbine is already undergoing verification testing at the site.
2 Digital Displacement is a trademark owned by MHI.

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