Highview explains liquid air plans

Company has released details on how its liquid air energy storage system would work commercially

Highview Power Storage has released additional details of how its liquid air energy storage system would work on a commercial scale.

The system, which is being trialled at a plant in Slough, provides a potential method of storing and releasing intermittent energy from renewable sources as an alternative to “pumped hydro” electricity storage schemes. 

Highview said a commercial plant would have an efficiency of 55-60%. “The integration of low-grade waste from industrial processes raises the system’s efficiency to around 70-80% depending on the temperature.” The pilot plant uses waste heat from a biomass-fuelled power station. 

Toby Peters, chief executive officer, said the capital cost of new liquid plant was a more important factor than efficiency in the development of liquid air. He cited a report by Imperial College London for the Carbon Trust that said: “Storage efficiency has been found to have limited impact on its value... as long as the installed capacities are low and the potential for arbitrage i.e. saving renewable curtailment remains high, storage can effectively displace high cost energy, even with low round-trip efficiency.”

Peters said: “We’re focusing on delivering a low-carbon grid and moving away from reliance on fossil fuels rather than acting as a back-up or peaking generator to simply keep the lights on.”

The Imperial report estimated that deploying energy storage could save £10 billion on grid infrastructure cost to 2050. “This must be accounted for in any like-for-like calculation,” said Peters. 

“It is also not reasonable to compare the costs of nascent with mature technologies. But our mature capital costs will be broadly competitive with a combined-cycle gas turbine, with additional environmental, sustainability and economic benefits. 

“Given we are using wrong time energy to charge the system, this will likely give better economic security than a reliance on imported fossil fuels in 10 or 20 years’ time.”