RheEnergise building waterless hydropower storage facility in UK

British company RheEnergise is launching work on a pilot facility that will use a dense fluid rather than water to store surplus energy from wind and solar power plants. This long-duration hydro storage solution is better than conventional pumped storage technology and cheaper than lithium-ion batteries, the firm claims.

RheEnergise’s so-called High-Density Hydro storage system is low-cost, energy efficient and environmentally benign. Rather than using water, the company has developed a fluid 2.5 times denser than water that can provide 2.5 times the energy compared to conventional systems, according to its press release.

The new solution can provide 2.5 times the energy compared to conventional systems

The solution is not 100% water-free as it mixes water with a proprietary mineral powder called R19 that turns it into a heavy fluid. However, it does allow for such gravity storage facilities to be installed in areas with much smaller hills as the required height differential between the upper and lower tanks is 40% smaller than in conventional facilities.

RheEnergise also claims its technology is cheaper than large-scale lithium-ion batteries, and that it can store energy for hours, days, weeks, months or even years, depending on local needs.

If the pilot project is successful, it might be followed by commercial-scale investments, the company added. Stephen Crosher, Chief Executive of RheEnergise, said it would like to have its first 10 MW grid-scale project in operation within two years.

Long-duration energy storage solutions are seen as critical for the energy transition

The development and commercial deployment of long-duration energy storage technologies, like RheEnergise’s HD Hydro system, is seen as essential for the world’s transition towards renewable energy, according to the press release.

The pilot facility, with a peak capacity of 500 kW, is being built at a kaolin mine in Devon in the United Kingdom, operated by international mining company Sibelco. The commissioning is expected to start in September.