Highview Power Storage is a London-based startup developing a frozen air (or "liquid air") technology for grid-scale storage applications.

Many interesting grid-scale storage technologies have cropped up in recent years including liquid batteries, compressed air storage, storage through electric vehicles, lithion ion - and the need is clear: if we want successful integration of intermittent renewables (ie. solar, wind) in grid infrastructure, energy storage is a key component -- as well as a major challenge, as we've already discussed.

Highview is commercializing the Cryo Energy System and the Cryo GenSet, systems based on inventor Peter Dearman's 50-year old idea to "store energy in cold".

The 'frozen air' energy process begins during off-peak hours, when electricity generated by renewables is used to cool air down to -310F, turning the air from gas to liquid.  The croygenic 'liquid air' is stored in a vacuum tank, and when electricity demand grows, the liquid air is warmed to ambient temperature, and the resulting increase in pressure drives a turbine for generating electricity.

 

Highview has built and successfully operated a pilot at the Slough Heat & Power station since 2010, and they expect to build commercial-scale projects in the upcoming year.

Highview admits that the current process is only about 25% efficient, but once systems are produced at scale, the conversion could be up to 70% efficient.

For other exciting energy storage technologies, see LightSail Energy, the Sadoway Battery, Better Place, and Watt Now's Energy Storage Page.