A British manufacturer of energy storage systems is collaborating with industrial giant GE in a move that could see its technology deployed all over the globe.
Highview Power Storage, a developer of liquid air energy storage technology, said it had signed an agreement with the oil and gas division of the US company. The deal covers the licensing of Highview’s technology to be used alongside GE gas turbines to store electricity and improve generation efficiency.
GE turbines are used in petrochemical plant worldwide to provide power. Highview has already developed a 350kW pilot plant adjacent to a Scottish and Southern Energy biomass facility in Slough, Berkshire, with the help of money from the Department of Energy and Climate Change (DECC).
In February, the government awarded Highview and Viridor, a recycling, renewable energy and waste management company, more than £8 million to build a new 5MW plant. Highview hopes its next installation of liquid air plant in Britain will be around 20MW, chief executive Gareth Brett told PE.
In the company’s 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, pumped to high pressure and sent to Highview’s patented evaporation and cold recycle unit, to capture and then later recycle the coldness 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.
GE may look at installing the technology next to gas-fired turbine installations of 40MW to 200MW, said Brett. “They are specialist, but there are a lot of them around. We want to start at the bottom end of GE’s range. There is work to be done to productise this. But the reach GE gives us is enormous.”
Tim Fox, head of energy and climate change at the IMechE, said the move indicated the recognition of energy storage as important technology in the US. “The fact that a major player such as GE is taking an interest in this innovative technology shows an increased interest in efficient electricity generation, and in energy storage per se. It’s no surprise to me that it’s a US company that’s got involved.”
One of the advantages of Highview’s technology is that it comprises components that are commercially available in the engineering supply chain – although, ironically, building small-scale plant does pose extra challenges because smaller components have to be made to order.
As well as GE, Highview has talked to Alstom, Siemens, Rolls-Royce and Weir Group about its technology, said Brett. The licence given to GE was specific to its gas turbine generators, and other deals with OEMs to spread the technology are possible, he said. “OEMs have been working to improve the flexibility of their gas turbine fleet to do the same kind of function. You need to be able to increase the ramp rate, increase efficiency at part load, and improve start-up times. They are working on all that.
“The advantage of putting our system alongside an open-cycle gas turbine is that the exhaust heat doesn’t go to waste. We can use that to drive our system, harnessing heat from the turbine exhaust. This gives more output to the turbine from the same amount of gas or oil you’re burning. It effectively makes GE’s product offering more competitive,” he said.
It is too early to say where GE might first install the technology. But Brett said the government’s backing for the technology was crucial. “DECC has done a lot with a small amount of funding. To my mind, energy storage is as important as carbon capture and storage, but there is an imbalance in money available.”
Energy storage technologies are expected to become increasingly important, since they can absorb excess power during periods of low demand and release it when needed.
Fox said that, in governmental circles, energy storage had a profile “orders of magnitude” higher than geo-engineering, because the former addressed the problem of intermittent electricity generation from renewables. Market mechanisms that encouraged the development of energy storage needed to be developed, he said.