Plymouth to host first ever demonstrator of High-Density Hydro® storage system

Over £32 million government funding has been awarded to UK projects developing cutting-edge innovative energy storage technologies that can help increase the resilience of the UK’s electricity grid while also maximising value for money.

Five projects based across the UK will benefit from a share of over £32 million in the second phase of the Longer Duration Energy Storage (LODES) competition, to develop technologies that can store energy as heat, electricity or as a low-carbon energy carrier like hydrogen.

The variable nature of renewables like solar and wind power means that energy can be produced when it is not needed, such as during extended periods of high wind. However, new energy storage technologies can store excess energy to be used at a later point, so the energy can be used rather than wasted – meaning we can rely even more on renewable generation rather than fossil fuels, helping boost the UK’s long-term energy resilience.

This builds on the aims set out in the Energy Security Strategy earlier this year, to ensure a more flexible, efficient system by encouraging flexibility with large-scale, long-duration electricity storage to balance the overall system.

Minister for Climate, Graham Stuart, said: “Accelerating renewables is key to boosting our energy resilience. Energy storage helps us get the full benefit of these renewables, improving efficiency and helping drive down costs in the long term.

‘This £32.9 million government backing will enable green innovators across the UK to develop this technology, helping create new jobs and encouraging private investment, while also safeguarding the UK’s energy security.”

The funding follows the first phase of the LODES competition, which saw £2.7 million awarded to 19 projects. This second phase provides further funding to the most promising projects from Phase 1, enabling them to build prototypes and demonstrators to bring their projects to life.

The LODES competition provides government backing to accelerate the development and commercialisation of innovative energy storage technologies, in turn supporting the UK’s transition to relying on renewables, while also encouraging private investment and new green jobs with an estimated 100 jobs supported through these projects.

UK company RheEnergise Ltd is developing a new and advanced form of long-duration hydro-energy storage system and will receive £8.24m to build a demonstrator near Plymouth of their ‘High-Density Hydro’ pumped energy storage system. The system uses an environmentally safe mineral-rich fluid more than two and half times denser than water, to create electricity from gentle slopes, without requiring steep dam walls or high mountains like traditional hydropower. The project will use surplus electricity to pump the fluid uphill, then later when electricity is needed by the grid, the fluid will be released back down the hill through turbines to generate electricity.

Stephen Crosher, Chief Executive of RheEnergise Ltd said:;“Over the next decade, Long Duration Energy Storage can make an important contribution to the UK energy market and indeed globally.;Long Duration Energy Storage is a key to delivering the energy transition and will help strengthen the resilience and security of the UK’s energy system. It will be essential to the effective operation of the grid as it balances intermittent renewable generation, it helps to create effective base-load power from renewables, whilst at the same time keeping costs low. Our storage system offers a solution.

‘BEIS’s contract is incredibly welcome and will enable us to accelerate the commercial deployment of our High-Density Hydro storage system in the UK and overseas. With the BEIS contract in place, we will be seeking planning consent for our Devon project before the end of the year.

‘We are also pursuing a number of project opportunities elsewhere in the UK, continental Europe and Canada. Drawing upon our work in Devon and the Government’s welcome support, we expect to have our first 5MW grid-scale project in operation in 2026.”