Integrated hydrogen system for tidal energy storage

EMEC has procured an electrolyser to convert power generated at its tidal test site in Orkney to hydrogen fuel.  The ground-breaking new project will pilot the storage of electricity from different forms of renewables, overcoming island grid constraints.


ITM Power, the energy storage and clean fuel company, has won a competitive tender to supply an integrated hydrogen system for use at EMEC’s tidal test site at the Fall of Warness, off Eday.

The system’s principal component is a 0.5MW ‘polymer electrolyte membrane’ (PEM) electrolyser with integrated compression and up to 500kg of storage. The total contracted value of the project is £1.79m.

The 0.5MW electrolyser will be used to absorb some of the excess power generated by the tidal turbines testing at EMEC. The hydrogen gas generated will be compressed and stored, with some of the gas being used in a hydrogen fuel cell to provide backup power to EMEC’s extensive data gathering and control systems.

The remainder of the hydrogen gas will be used off-site by a further project being developed separately – Orkney Surf and Turf – which plans to absorb output of a local community wind turbine operated by Eday Renewable Energy Ltd.

The electrolyser will be packaged in a standard 20’ and 10’ ISO container with hydrogen generation capacity up to 220kg/24hours.

Neil Kermode, Managing Director, EMEC, commented:

“We are really excited about the deployment of ITM Power’s electrolyser system on Eday. The electrolyser will allow us to pilot the production of hydrogen fuel from tidal energy, and allow surplus renewable energy on the island to be used without having to rely upon the inadequate grid. We expect to have this installed and working within the next year.

“While people are doing this all around the world already in some respects, we don’t believe anybody is doing it from tidal energy. This is an innovative way to tackle the shortcomings of the local grid which is holding back marine energy in Orkney.  We really see this as the moment we begin to break away from the shackles of the 20th century cable architecture.”

Michael Rieley, Senior Policy Manager, Grid and Markets at Scottish Renewables, said:

“Bringing together tidal devices and wind energy like this is a hugely inspiring way to solve one of our energy system’s greatest challenges – how to store electricity which is produced when it is not immediately needed or unable to reach its demand.

“Orkney’s current connection to the mainland electricity grid is not suitable for transmitting the large amount of power produced by renewables on the islands. This project perfectly demonstrates the sort of ingenuity which constraint has bred, and we would like to see more innovative solutions like this applied across the GB electricity network.”

Dr Graham Cooley, CEO, ITM Power, commented:

“We are delighted with this sale and to be working with EMEC on the Orkney Islands.  ITM Power’s PEM Electrolysers are perfect for island deployment given the logistics of power distribution and fuel supply and this application by EMEC is a fantastic example as to how the rapid response functionality of ITM’s systems offer freedom from the grid constraints of distributed and remote renewable energy”.