Seeking a larger role in the energy storage sector, General Electric Oil & Gas has signed a global licensing and technology collaboration agreement with Highview Power Storage, a UK supplier of large-scale liquid air energy storage systems. The companies will explore opportunities to integrate Highview’s liquid air storage technology in power plants where GE gas turbines and gas engines are currently or will be installed.
Highview’s technology uses liquid air or nitrogen as the storage medium to provide long-duration energy storage without geographical requirements – such as mountains or caverns. The technology also can convert low-grade waste heat into power, increasing the overall efficiency of a host power plant.
In February 2014, the UK Department of Energy & Climate Change awarded Highview and waste management company Viridor more than $13 million to build a new 5 MW/15 MWh liquid air energy storage demonstration plant. The facility will be powered by a GE Oil & Gas turbo-generator and will demonstrate the technology at commercial scale for the first time when it begins operating in the spring of 2015.
With Highview’s energy storage process, ambient air is drawn from the environment where it is cleaned, compressed and then refrigerated. Once liquefied, it is stored in an insulated storage tank at low pressure during off peak demand periods. When power is required, the cold liquid air is drawn from the tank and pumped to high pressure and sent to Highview’s evaporation and cold recycle unit, in order to capture and then later recycle the cold required for the liquefaction process. The re-gasified air is then heated by waste energy present at the exhaust of the gas turbine or engine, and expanded in a multi-stage process gas expander, which drives the generator to produce electricity.
The Highview technology is scalable from around 5 MW to greater than 50 MW.