A 1.8MWh vanadium redox flow battery (VRFB) has been installed and energised at the European Marine Energy Centre (EMEC) test site in Scotland’s Orkney Isles.
The energy storage technology will be combined with generation from tidal power to produce continuous supply of green hydrogen at the facility on the Orkney Island of Eday.
As reported by Current as the project was announced in November 2020, tidal power is predictable, but its generation profile is highly variable between two high tides and two low tides each day. That makes smoothing its output a very heavy-duty cycling application for batteries.
Technology provider Invinity’s flow batteries, capable of more rugged performance and thousands of duty cycles without degradation, are being trialled to see if they will be a more suitable fit for the project than lithium-ion, which is considered to have technical limitations in that regard.
The VRFB system “will integrate power generated by our clients’ tidal turbines and help optimise hydrogen production,” EMEC managing director Neil Kermode said yesterday (18 August).
“Energy storage solutions like vanadium flow batteries are crucial to creating resilient, clean energy systems of the future and we look forward to seeing the integrated system fully demonstrated later this year.”
The VRFB comprises 48 of Invinity’s VS3 battery modules which in combination with tidal power generators will feed EMEC’s 670kW hydrogen electrolyser.
Kermode noted that getting the system installed on a remote Scottish island was already a challenging prospect, but the Invinity and EMEC teams also had to contend with doing so safely during the pandemic.
The flow battery system was manufactured at Invinity’s production plant in Bathgate, Scotland.
The overall project’s final commissioning phase includes integration of the tidal turbine and electrolyser, which is expected to complete shortly with full demonstration of the complete system to begin this autumn.
Also this week EMEC announced that it has been awarded a £454,000 grant for two hydrogen tube trailers which will facilitate supply of the green hydrogen produced to the Scottish mainland.
Current reported in late July 2021 that the site’s 2MW tidal turbine, claimed to be the most powerful of its type in the world today, had begun generating power, which will go to the grid as well as into the flow battery-electrolyser hybrid project. The 74-metre turbine was manufactured in Dundee by Orbital Marine Power.
In related news, last October a consortium applied to develop green hydrogen production facilities on the Orkney Isle of Flotta, through offshore wind generation. Consortium members Macquarie’s Green Investment Group, TotalEnergies and Scottish developer Renewable Infrastructure Development Group (RIDG) said the production centre could provide an alternative route to market for offshore wind generation.