The ability to store energy is vital for the UK’s power network, and recent technological advancements have revolutionized these systems on a varied scale. The latest storage technology includes the likes of molten-salt thermal storage units and those using liquid air.
Renewable energy is a cornerstone of the UK’s power supply but poses challenges due to unpredictable weather. The UK’s electricity is generated about one-third by wind and solar energy, but power generation can fluctuate due to weather conditions, posing an issue of intermittency. Nathan Ritson, a technical manager at Good Energy, highlights these challenges.
The solution lies in electricity storage technology. Batteries for energy storage are becoming more commonplace both domestically and commercially, playing an essential role in balancing supply and demand across the grid.
Surplus electricity storage is pivotal as reliance on renewable energy sources grows. However, batteries aren’t the only players in the field of energy storage. Flywheels, liquid air, and molten salt technologies are emerging as valuable contributors towards future energy solutions.
A long-standing technology, flywheels, have evolved to serve in energy storage. The basic principle involves a power source spinning a rotor, storing energy in motion form that can later generate electricity. Independent energy consultant Eugene Bryce shared that flywheels are extremely efficient, can be quickly charged and discharged, and have a longer lifespan than batteries. However, their initial costs are high and would need to be used in combination with batteries for significant power storage.
On the other hand, liquid air technology is a newer addition to energy storage solutions. Air is compressed using surplus electricity, then cooled until it becomes a liquid. When energy is needed, the liquid is pumped out as a gas, driving turbines to generate electricity. The world’s first commercial-scale application of this technology is underway in Manchester by Highview Power, anticipated to go online in 2027. According to energy storage specialist Shaylin Cetegen, liquid air technology could emerge as a cost-effective option for large-scale storage despite the initial economic hurdles.
Another innovative storage method employs molten salt. Concentrated solar plants use mirrors to heat thermal oil, producing steam to generate electricity. This heat is focused on special mixtures of salts that can store it for extended periods. When electricity is needed, the hot molten salt is pumped to a steam generator, producing superheated steam to drive turbines. Aside from electricity, this heat can also be used in industrial processes. Robert Barthorpe, a storage expert at the University of Sheffield, regards molten salt as a promising technology for industrial-scale high-temperature storage.
