Battery bolsters tidal power for hydrogen productionS. Himmelstein | November 13, 2020
A vanadium flow battery will operate in concert with a tidal energy system to power a hydrogen production plant at the European Marine Energy Centre (EMEC) tidal energy test facility on the island of Eday, Scotland. The 1.8 MWh battery system from Invinity Energy Systems, composed of eight VS3 linked modules, is expected to be operational in 2021.
The added energy storage capacity will help smooth out the variability of the tidal energy system associated with two high and two low tides each day. By storing electricity produced during high tidal periods for use during low power periods, the battery component will supply on-demand electricity for EMEC’s 670 kW hydrogen electrolyzer. Vanadium flow batteries deliver hours of continuous power and durable performance in applications where available lithium-ion batteries would degrade.
The Invinity battery is composed of two separate tanks of vanadium electrolyte with different charges, both of which are connected to a central fuel cell stack. Electrolyte from the tanks is pumped through the fuel cell stack, where ion exchange occurs across a membrane and induces a reversible electrochemical reaction, allowing electrical energy to be stored and subsequently discharged.
Neil Kermode, managing director at EMEC, said, “EMEC’s core purpose is to demonstrate technologies in new and inspired ways to decarbonize our energy system. This is the first time that a flow battery will have been coupled with tidal energy and hydrogen production and will support the development of the innovative energy storage solution being developed in the Interreg NWE ITEG project.
“Following a technical review looking at how to improve the efficiencies of the electrolyzer we assessed that flow batteries would be the best fit for the energy system. As flow batteries store electrical charge in a liquid rather than a solid, they can provide industrial quantities of power for a sustained period, can deeply discharge without damaging itself, as well as stand fully charged for extended periods without losing charge. These are all necessary qualities to integrate battery technology with the renewable power generation and hydrogen production process.”