Developed by RheEnergise, the 500kw pilot project is the first time the high density hydro technology has been tested in the real world.
The site consists of an upper reservoir of tanks built into a hillside at Cornwood, near Plymouth, with the lower reservoir and power house below. Electricity is used to pump the fluid to the upper reservoir where it is stored, flowing back down the hill to turn turbines when the power is needed.
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In addition to the pumped hydro plant itself, the Devon site also features a temporary mixing shed to produce the high density fluid, which is said to be environmentally friendly. Developed in partnership with Cambridge firm 42 Technology, the semi-automated processing plant demonstrated that the proprietary fluid can be mixed at scale on site, ready to be dropped into the pumped hydro system. The project has been supported by the UK government via the Department of Energy Security & Net Zero’s ‘Net Zero Innovation Portfolio’ programme.
“Storing energy will play an increasingly important role as we transition to clean power,” said Lord Patrick Vallance, UK Minister for Science, Innovation, Research and Nuclear.
“RheEnergise’s first-of-a-kind system has the potential to strengthen our future long duration energy storage (LDES) capabilities. Scaling up innovations like these is essential as the UK’s energy demand grows and we move to a clean power system that we control.”
Using a high density liquid rather than water means the height between the upper and lower reservoirs can be much smaller compared with traditional pumped hydro. This will enable the new technology to be sited in locations that were previously not suitable for pumped storage, using hills rather than mountains.
RheEnergise claims it has already identified over one million potential sites for the technology worldwide, including almost 62,000 in Australia and more than 23,000 in Saudi Arabia, two countries with abundant solar resources. Having proven the technology works and can deliver consistent power, it is now seeking to raise additional funds and move towards commercial deployment. The company is aiming to have its first commercial-scale project in operation within the next three years and is looking at potential sites in the UK, continental Europe and North America.
“Commissioning our 500kW demonstrator is a major step in proving our unique approach as a practical LDES solution” said Tamás Bertényi, CTO at RheEnergise.
“42 Technology’s process design and automation experience has been vital in getting us to this point and validating our fluid-production method under real-world conditions. As grids move towards 100 per cent renewables, dependable long-duration storage like this will be essential.”
