Renewable sources of energy are getting more efficient by the day – yet energy storage remains an obstacle standing in the way of wide adoption. To fill this gap, some companies are thinking outside the box and investing in developing energy storage that relies on cold air. “Compressed air is an interesting technology,” Ravi Manghani, director of energy storage at Greentech Media told the BBC. “It can be a form of bulk storage.” Alacaes in Switzerland is one company that has explored cold air energy storage by drilling a hole in the side of the mountain, in which compressed cold air is stored until needed to drive a turbine. Read on to learn more about this and other efforts to hold energy in cold air.
Alcaes’s mountain drilling technique may prove effective, though it is limited in its applications. “The downside is it has to rely on specific geological formations… It needs underground caverns which in itself is a limitation,” said Manghani. The United Kingdom-based Highview Power Storage is pioneering an alternative method for cold air energy storage by using refrigeration to cool air to -196 degrees Celsius, at which point air becomes liquid. This liquid air is then held in low pressure environments until it is needed.
Highview has constructed a facility near Manchester that uses heat generated by burning waste gas from a landfill to expand liquid nitrogen in the stored air. The expanded air is then channeled through a turbine, which generates electricity. Highview expects this facility to be connected to the UK energy grid in spring 2018. Highview hopes their facility will serve as a model for a planet that desperately needs clean energy storage solutions. “Globally the world is realizing that true grid scale, long duration storage is a requirement if we’re to go for a decarbonised future,” Stuart Nelmes, Highview’s engineering director, told the BBC, “and this tech will play a key part in that.”