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New Energy World magazine logo
New Energy World magazine logo
ISSN 2753-7757 (Online)

Shell joins wave powered subsea energy project


View of underwater wave powered device from above Photo: Verlume
Halo seabed battery energy storage system being deployed as part of the Renewables for Subsea Power (RSP) collaborative project which is powering subsea equipment off the coast of Orkney through a combination of wave power and subsea energy storage

Photo: Verlume

Shell has joined an innovative collaborative project called Renewables for Subsea Power (RSP), which is powering subsea equipment off the coast of Orkney using a combination of wave power and subsea energy storage.

The £2mn demonstrator initiative 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.


Located 5 km east of Orkney, the project connects a Blue X wave energy converter, built by Edinburgh company Mocean Energy, with a Halo underwater battery storage system developed by Aberdeen intelligent energy management specialist Verlume. Nearing one year of operations in the water, the project has demonstrated that a subsea battery storage system, recharged using wave energy, can reliably power subsea equipment such as remotely operated autonomous underwater vehicles (AUV).


The new investment has come via the Shell Technology – Marine Renewable Program. Shell joins project leads Mocean Energy and Verlume, alongside Baker Hughes, Serica Energy, Harbour Energy, Transmark Subsea, PTTEP, TotalEnergies and the Net Zero Technology Centre (NZTC).


Graeme Rogerson, Head of Net Zero Technology at NZTC, says: ‘Mocean Energy’s Blue X wave energy converter and Verlume’s Halo underwater battery storage system have demonstrated their effectiveness in delivering low-carbon power and communication to offshore subsea infrastructure. Shell’s investment and the opportunity to continue to test in a real-world environment will help to further progress the technologies.’


The Orkney deployment is the third phase of the RSP project. In 2021, the consortium invested £1.6mn in phase two of the programme – which saw the successful integration of the core technologies in an onshore test environment at Verlume’s operations facility in Aberdeen.


In 2021, Mocean Energy’s Blue X prototype underwent a programme of rigorous at-sea testing at the European Marine Energy Centre’s Scapa Flow test site in Orkney, where it generated first power and gathered key data on machine performance and operation.  


The company is developing two wave energy technologies based on the Blue X concept of ‘a hinged raft with a unique geometry that improves performance by up to 300% compared to traditional hinged rafts and increases survivability by diving through the largest waves’:

  • Blue Star, a device to power a range of subsea equipment, inspection and maintenance systems; and  
  • Blue Horizon, a larger machine designed to generate grid-scale electricity.


According to Mocean Energy, ‘Harnessing just 1% of global wave power resource could power more than 50 million homes and save more than 50mn t/y of CO2.’


Verlume’s seabed battery energy storage system, Halo, has been designed for the harsh underwater environment, reducing operational emissions and facilitating the use of renewable energy by providing an uninterrupted power supply. Halo’s intelligent energy management system, Axonn autonomously maximises available battery capacity in real time.