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Wind Turbine

DOT Wind Turbine

The DOT wind turbine combines our innovations into one industry disrupting package. Connecting our Hydraulic drivetrain with the Pelton generator for the production of electricity, reverse osmosis for clean water and using the output of both to create hydrogen creates a unique system that can be tailored to a wide range of projects and/or purposes.

Offshore wind has become an established industry with the highest projected growth rate within renewables. As most offshore wind technology is still based on onshore methodologies, the industry has seen limited technology innovations over the past 20 years which means that the limits of upscaling conventional wind turbines will be
reached soon. The DOT turbine is designed with significant weight reduction in mind resulting in the ability to build larger turbines at a lower cost.

This combined with the flexibility in the technology end-applications (electricity, fresh water and/or hydrogen) and improved installation methods, such as the slip joint, show that we are aiming to radically innovate the wind energy industry.

Process Timeline

  • Onshore full scale testing

    A fully operational 500kW hydraulic wind turbine including wind turbine control via spear valve and a slip joint was tested onshore at the Maasvlakte in the Port of Rotterdam.

    View the video of the construction and testing here

  • Offshore full scale testing

    Commissioning, operation, certification and decommissioning of the DOT turbine including a full scale slip joint and monopile installation.

    • Proof of slip joint concept
    • Level D, B & C type certification (DNV-GL)
    • Single lift installation of a WTG in combination with a floating installation vessel

    View the video of the construction and testing here

  • Reverse osmosis pilot

    Design, construction and testing of a 500kW wind powered electricity and seawater desalination plant.

    • Control of a wind turbine via spear valve in combination with a SWRO membrane
    • Proof of DOT wind powered desalination concept
    • Insight in pre and post water treatment requirements

    View the video of the working principle here

  • Floating installation of an XXL offshore wind turbine

    Demonstrating floating installation of our large offshore wind turbine combining Heerema’s Rotor-Nacelle assembly with the slip joint technology. Successful demonstration of:

    • Rotor Nacelle assembly
    • Slip joint based seafastening
    • Nacelle – Tower slip joint

    View the video of the installation here

Other innovations

All our innovations are supported by an extensive track record of studies, prototypes and offshore testing. Our approach is to “put steel in the water”: relentlessly testing the concepts in its designated environment of operation.

Hydraulic Drivetrain

The core of the DOT concept is a sea water pump directly driven by the turbine rotor. It is capable of slow rotation speed, high pressure and high-power output.

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Wind Turbine

Operating a water-pumping wind turbine allows for different control strategies. DOT develops these during the integration of the pump in different turbine platforms.

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Pelton Turbine

Power conversion from high-pressure seawater is done using hydropower technology a pelton wheel driving a generator. DOT creates an unprecedented 4km hydraulic head.

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Reverse Osmosis

High pressure seawater can also be used through a reverse osmosis system. The DOT turbine takes out several energy conversion steps to arrive at renewably cleaned water for drinking, irrigation or H2 production.

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Slip Joint

Speedy installation of the thousands of megawatts offshore wind is crucial to meet the Paris goals. The slip joint removes many cumbersome offshore handling operations, allowing single lift turbine installation.

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Beyond the slip joint, DOT supports innovations on pile driving technology, monopile design and cable and pipeline installation. The “steel in the water” drive makes DOT a valuable partner in Joint Industry Projects.

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