The energy storage tech uses a patented fluid which is two and half times denser than water and is equally efficient at 40 percent volume.
RheEnergise, a UK-based energy startup developing new high-density hydro storage technology, is setting up a 500 kilowatt (kW) demonstrator at a mining site near Plymouth. The first-of-its-kind facility aims to help decarbonize the site’s energy consumption and is supported by the government’s Longer Duration Energy Storage (LODES) Demonstration Programme.
Water-based energy storage isn’t a radically new concept. Additional power generated from renewable energy plants can be used to pump water up from a lower reservoir to one located at a higher level.
When the energy supply is low, water from the higher reservoir is released back to the lower one, where it passes through turbines generating electricity. While the technology seems straightforward, Switzerland spent 14 years constructing one such energy storage system in the Alps.
Even if the industry were willing to spend many years building such systems in other parts of the world, for the technology to be effective, one needs high mountains and ample water, which isn’t available equally everywhere.
A Waterless hydro energy system
RheEnergise is looking to solve this problem by moving to a waterless system. The company has patented a fluid that is two and a half times denser than water and, therefore, needed in much lesser quantity to generate the same amount of power.
According to the company’s estimates, the energy generation capacity of its fluid is the same as that of water but at 40 percent volume. Therefore, the fluid can be stored in Olympic-sized pools instead of building large reservoirs.
Further, the fluid’s energy delivery capacity is higher. It can generate the same output as water even when the height differential between the tanks is 40 percent. This effectively means that the system can also be installed on smaller hills, making it easier to erect such infrastructure.
Decarbonizing energy usage
According to RheEnergise, there are 6,500 potential sites in the UK alone. It is building its first full-scale demonstrator at Cornwood near Plymouth, where kaolin is mined. The mineral has industrial applications and is used to make sanitary ware, tiles, and ceramics.
Construction of the 500-kW demonstrator plant has already begun, and the site is expected to be operational by September of this year. When ready, the facility will support the mining plant’s energy demands by supplying carbon-free electricity.
Details on how much of the site’s energy consumption will be offset this way or how much it costs to build and operate it aren’t available. However, the company told New Atlas its technology is much cheaper than large-scale lithium-ion storage solutions.
Additionally, energy storage does not have the same problems as batteries that leak or degrade over time. So, energy can be stored for months or even years without losses.
“The demonstrator is a trailblazing project for the LDES sector and will place us in a strong position to build commercial-scale projects in this country and overseas,” said Stephen Crosher, Chief Executive Officer of RheEnergise, in the press release.
“We have global interest in our technology, from as far as Australia and Chile. We would like to have our first 10MW grid-scale project in operation within two years.”
