Hydrogen, gravity and heat: BEIS provides fresh funding for innovative energy storage technologies

Pictured: An artist's impression of Gravitricity's solution

The funding for the innovative projects totals £6.7m and is being provided by the Department for Business, Energy and Industrial Strategy (BEIS) as part of its Longer Duration Energy Storage Demonstration competition. This competition will allocate £68m in total, all from the £1bn Net-Zero Innovation Portfolio.

Projects supported at this point in the competition are all first-of-a-kind prototypes of full energy storage systems, with Government funding intended to support the delivery of feasibility studies.

One of the projects receiving backing is Edinburgh-based Gravitricity, which is developing an energy storage system that works by raising a range of weights within deep shafts. Electrical power can be absorbed or generated by raising and lowering the weights. This system, the firm claims, could be used to deliver storage arrays ranging from 1 to 20MW.

Gravitricity is aiming to complete its feasibility project by the end of the year following the launch of a demonstrator project in Leith last summer.

“Finding low-cost, long-life ways to store renewable power will be crucial in the world’s journey to net zero,” said Gravitricity’s managing director Charlie Blair.

 “Our multi-weight concept has been proven by our Leith demonstrator where two 25-tonne weights were configured to run independently, delivering smooth continuous output when lowered one after the other. We were able to demonstrate a roundtrip efficiency of more than 80% and the ability to ramp up to full import or export power in less than a second.

“A Gravitricity system with multiple weights offers a lower cost per MWh of energy stored – more weights give more mass (or MWhs) whilst the number of hoisting systems (which forms a substantial part of asset cost) does not increase.”

Other technologies receiving backing from BEIS at this stage are domestic-scale thermal batteries from Scottish firm Sunamp; compressed air energy storage from Cheesecake Energy and green hydrogen storage solutions from Northern Irish firm B9 Energy Storage. On this latter point, the UK Government’s Hydrogen Strategy targets 5GW of domestic low-carbon hydrogen generation by 2030, with some key industry players pushing for this to be increased to 10GW.

The competition is also providing funding to Sheffield-based ITM Power for its Ripcurl project, which is developing next-gen electrolysers for green hydrogen production.

Other technology options receiving backing from BEIS at this stage include hydrogen storage using methods currently used to store tritium and deuterium; grid-scale pumped thermo lithium-sulphur based flow battery technology.

Energy storage is regarded as necessary to maintaining energy security as the energy mix decarbonises, as it helps to overcome the intermittent nature of renewable electricity generation. However, batteries are often not able to store energy for long periods of time and degrade over time – hence the Government’s exploration of next-gen alternatives.

Energy and Climate Change Minister Greg Hands said: “Driving forward energy storage technologies… will allow us to extract the full benefit from our home-grown renewable energy sources, drive down costs and end our reliance on volatile and expensive fossil fuels. Through this competition, we are making sure the country’s most innovative scientists and thinkers have our backing to make this ambition a reality.”

BEIS notably committed, last year, to bringing all unabated fossil-fuelled electricity generation offline by 2035. Further details on the delivery of this ambition are expected in the coming months. The Government has already moved to double the pace at which funding is provided to renewable energy generators through its Contracts for Difference (CfD) auctions.

Future forecast

The funding announcement comes in the same week that Aurora Energy Research published a new report outlining the future role of long-duration energy storage in the UK.

The headline finding is that up to 46GW of energy storage would be needed in the UK to deliver the upcoming carbon budgets agreed by the Government and the decarbonisation ambitions of National Grid. Up to 24GW of this, the report states, should be long-duration. This level of uptake could mitigate 50 TWHth of gas use in the UK in 2035, according to the report.

Long-duration is defined in the report as having a minimum of four hours. Technologies covered include pumped hydro, liquid air, flow batteries, compressed air, gravitational storage, thermal storage and hydrogen-to-power.

Bringing some of the less mature technologies to scale, the report argues, will need additional policy support beyond grant funding. It recommends the introduction of a cap and floor mechanism in the balancing market, similarly to the mechanism currently in place for interconnector developers. It also recommends that Ministers take a joined-up approach to both energy storage and nuclear power as ways to maintain energy security in a decarbonised economy.

Sarah George