Scots firm Gravitricity has secured a £912,000 grant from the Department of Business Energy & Industrial Strategy (BEIS) to develop plans for a multi-weight energy storage system – to be built on a brownfield site in the UK.
The Edinburgh-based energy storage specialists will work alongside control and simulation experts Industrial Systems and Control (ISC), winch specialists Huisman and Careys Civil Engineering to deliver the front-end engineering design (FEED) for a 4MWh, multi-weight system using a custom-built shaft.
They will also work closely with a site partner to secure the planning consents required to develop and build their multi-weight gravity energy store at a grid-connected site in northern England.
The Gravitricity system stores electricity by raising and lowering heavy weights in a shaft. Analysts at Imperial College predict the firm’s patented multi-weight concept will offer long duration energy storage at a lower cost than alternative technologies, including lithium ion batteries.
The feasibility project will complete in late 2022 and will provide the information required to commence build of the full-scale commercial prototype multi-weight gravity energy store immediately thereafter, subject to securing planning permission and the necessary funds.
The company is also advancing plans to build a full-scale single-weight project in a disused mine shaft in mainland Europe, to commence this year.
The £1.5 million feasibility project follows the success of the company’s 250kW demonstrator, which was commissioned and operated in Leith, Edinburgh, during summer last year.
The FEED study is being supported by the BEIS Longer Duration Energy Storage Competition, a competitive funding scheme to accelerate the commercialisation of innovative energy storage projects which can contribute to net zero. Gravitricity secured a grant of £912,410 towards the £1,520,684 project cost (representing 60 percent funding intensity for SMEs).
Gravitricity Managing Director Charlie Blair said: “Finding low-cost, long-life ways to store renewable power will be crucial in the world’s journey to net zero.
“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 percent and the ability to ramp up to full import or export power in less than a second.”
He added: “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.
“This project will demonstrate multi-weight use and control using a single set of hoisting equipment and will pave the way to custom projects which can be built wherever they are required,” Blair says.
The project has been welcomed by UK Government Energy and Climate Change Minister Greg Hands who said: “Driving forward energy storage technologies will be vital in our transition towards cheap, clean and secure renewable energy.
“It 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.”
The second phase of the project will see Gravitricity commence construction of a first of kind commercial prototype system at a grid-connected site in the north of England. The company anticipate that a substantial amount of the mechanical design and optimisation of hoisting equipment for fast response applications will be directly transferable from this project to all future applications, as will the control systems being developed.
As future production ramps up, Gravitricity and its partners intend to produce modular systems which will bring fabrication costs down considerably. At the point where multiple schemes are being implemented, the consortium will be able to purchase and operate their own shaft sinking equipment using, offering substantial savings and further improvements to the cost of energy storage.
