WITH the help of modern technology from SKF, another source of power from nature, besides sun and wind, is being tapped: that of the moon.
Strong currents arise where the ebb and flow of tide squeeze between islands. These are particularly powerful off the Orkney Islands, which is why experiments with tidal current power plants have been carried out here for several years; specifically at the European Marine Energy Centre (EMEC). Today EMEC is Europe’s leading test site for tidal and wave energy projects.
Orbital Marine Power, Scottish-based developer of the world’s leading floating tidal turbine technology, has now launched its first commercial 2MW unit, the Orbital O2, which will soon be installed at EMEC, where it will become the world’s most powerful operational tidal turbine.
About 15 metres below the O2’s 72-metre-long superstructure, two fully integrated power trains from SKF are attached on two wing-like legs. Here the twin-bladed rotors rotate, each with a diameter of 21 metres, the largest ever on a single generating platform to date, driven by the tidal current. The electricity generated in the generators is conducted ashore via a subsea cable, where it can be fed directly into the grid, stored or processed into “green hydrogen”.
SKF delivered the fully integrated holistic power trains as “plug & play modules” to Scotland. The 1MW power trains, as used in the Scottish Orbital project, complement the generation of electricity from solar and wind power.
The tides are reliable, the flow of electricity is predictable, and the energy density due to the working medium seawater is very high.
Within the Orbital O2 power trains, SKF core competence is not only found in the main bearings, gearbox bearings and in the slewing bearings for pitching the rotor blades, but also in the seawater seals of the main shafts between the rotor hub and the nacelle housing. And SKF also provides the “CoMo” condition monitoring for the entire system and various lubrication systems.
Experts see ocean energy devices that generate energy from wave or tidal power as an important pillar of the renewable energy transition. In its current offshore strategy, the EU Commission is aiming for 40 gigawatts of ocean energy by 2050 – generated from ocean energy devices, floating photovoltaic systems and by using algae to produce biofuels.
The O2 project has also received funding from the European Union’s Horizon 2020 research and innovation programme under the FloTEC project as well as the European Regional Development Fund through the Interreg North West Europe programme under the ITEG project.