Orkney, Scotland’s European Marine Energy Centre (EMEC) in Orkney has completed what it says is a world-first demonstration combining tidal energy, battery storage and hydrogen production, solving multiple energy problems at once.
The demonstration successfully integrated three technologies – Orbital Marine Power’s O2 tidal turbine, vanadium flow batteries supplied by Invinity Energy Systems, and an ITM Power 670 kW electrolyser–which splits water into oxygen and hydrogen–at EMEC’s onshore site on the island of Eday.
The team tried moving the energy flow in various ways. During times when a lot of power was being generated from ocean tides, power from the turbine was used to charge the battery system, supply electricity directly to the electrolyser and export power to the grid. When tidal generation was low, the battery system discharged power to the electrolyser to keep it operating and creating green hydrogen which is a promising fuel for hard-to-abate industries such as shipping.
“This world-first demonstration represents the culmination of years of effort to integrate tidal energy, battery storage and hydrogen production. Bringing together three innovative technologies was a complex challenge, but reaching this milestone has provided invaluable insights,” said Leonore Van Velzen, Operations and Maintenance Manager at EMEC.
“Running all planned scenarios, responding swiftly to an electrolyser trip and identifying opportunities for greater automation have given us a clear roadmap for optimising future systems. The trial also highlights an alternative pathway for tidal energy in scenarios where grid export capacity is limited, a likely feature in the future as we transition to a fully renewable energy system.
This approach effectively smoothed out the cyclical nature of tidal energy, enabling on-demand electricity to power the electrolyser for hydrogen production. In addition, battery power was used to support operations at EMEC’s onshore Caldale site.
“Tidal energy offers a predictable source of renewable power, and this demonstration shows how we can unlock its full potential through innovative integration,” said Andrew Scott, CEO at Orbital Marine Power. “By maximising generation through battery storage, we minimise curtailment and enable industrial offtake that can achieve higher decarbonisation, creating new markets for tidal energy and providing valuable services like grid balancing.
The team tried all planned operational scenarios and safety mitigation measures, including adding new ones, such as the ability to respond within seconds when an electrolyser tripped, preventing a full site shutdown. The demonstration validated the 3-in-1 concept, highlighted areas for improvement such as battery management and electrolyser controls, and underscored the value of increased automation to minimise human error and enhance system reliability.
The demonstration was part of the Interreg North-West Europe funded project, ITEG, which explored how tidal and hydrogen production could be combined as a solution in coastal areas to overcome grid constraints. It has also been supported with funding from Scottish Government via Highlands and Islands Enterprise, and by the EU-funded FORWARD2030 project which has completed detailed monitoring study into how to optimise the integration of tidal energy and battery storage with hydrogen and other offtake routes.
“Building on our practical experience with hydrogen, we’re now exploring other offtake routes such as synthetic fuel production using renewable hydrogen as a feedstock, a practical solution to decarbonise hard-to-electrify sectors like aviation and maritime,” Van Velzen said. “This is especially relevant to Orkney, and we’re excited to keep driving clean energy innovation.”
