A next-generation wave energy converter (WEC) fitted with an underwater battery has been deployed as part of a trial of the technology as a power source for subsea oil & gas and carbon capture and storage infrastructure off the UK.

The Mocean Energy ‘Blue X’ WEC, wired into a Verlume ‘Halo’ battery, will be run off Orkney, Scotland, as part of the £2m ($2.4m) Renewables for Subsea Power (RSP) pilot backed by Baker Hughes, Serica Energy, Harbour Energy, Transmark Subsea and the Aberdeen-based Net Zero Technology Centre.

“This is a natural next step for our technology,” said Mocean managing director Cameron McNatt. “The new test site east off Deerness offers a much more vigorous wave climate and the opportunity to demonstrate the integration of a number of technologies in real sea conditions.”

Andy Martin, chief commercial officer at Verlume, said: “This offshore test programme… will provide an opportunity to gather high quality performance and operational data which will support the further electrification of the subsea sector.”

The 10kW wave-riding demonstrator unit, which will be connected to Baker Hughes’ subsea controls equipment serviced by a Transmark autonomous vehicle, aims to show “how green technologies can be combined to provide reliable low carbon power and communications to subsea equipment, offering a cost-effective alternative to umbilical cables”.

Alex Seinuah, Baker Hughes growth hub leader, said: “The integrated deployment of our renewable subsea power solution in Orkney is a historic moment for all partners involved.”

The Orkney deployment, for which the European Marine Energy Centre (EMEC) has supplied instrumentation to measure the speed and direction of currents, is the third phase third phase of the RSP project.

In 2021, the Blue X prototype underwent a programme of rigorous at-sea testing at the EMEC Scapa Flow test site.

According to Ocean Energy Europe (OEE) figures, 30.2MW of tidal stream technology has been installed off Europe since 2010, 17.2MW of which has been decommissioned as projects successfully completed testing programmes, and some 12.7MW of WECs, 12.3MW has since been pulled out of the water.

Global ocean energy deployments since 2010 now tot up at 41.2MW for tidal and 24.9MW for wave, with Canada emerging as “a highly attractive market” for developers with a project pipeline of 32MW, said OEE, which noted China added more tidal energy capacity than Europe in 2022, via the addition of a 1.6MW turbine at the grid-connected Hangzhou demonstration project off Xiushan Island.