A South Australian company that has developed technology to store electricity as thermal energy will build its first commercial systems at the Tonsley Innovation Hub this year. By Andrew Spence

1414 Degrees has developed a technique to store energy by heating and melting silicon – the second-most abundant element in the Earth’s crust after oxygen. It is being billed as a storage solution for renewable energy producers such as wind farms and solar arrays, which have come under scrutiny in recent months as South Australia grapples with issues surrounding its electricity supply. A tonne of silicon can store enough energy to power 28 houses for a day. The process also produces cheap, useable and clean heat.

The company completed its first trials in September with a small prototype test system using about 300kg of silicon to store about 150kw of energy. 1414 Degrees is now scaling up its technology to grid scale thermal energy storage systems with the potential to dramatically improve the efficiency of wind and solar farms.

Chairman Dr Kevin Moriarty said 1414 Degrees had two target markets: a device capable of storing 10MWh of energy aimed at industry; and a second 200MWh device that would be suitable for a wind farm, large solar array or gas-fired power station. As well as its ability to stabilise South Australia’s electricity supply, which relies heavily on wind power, the system is likely to appeal to northern European countries because of its ability to store the wind energy of a cold Scandinavian night while keeping residents warm and running their computers the next day.

“It’s low cost for very large energy storage,” Dr Moriarty said. “We’re not really competing with batteries, we’re going to be working in the space of district heating, major industry, electricity producers and suburb-scale residential developments.

“The big problem with renewables is this need to shift the peak – we’ve got wind turbines roaring away at 3am in South Australia when nobody needs the power. That problem is huge in Europe as well – you need to match the demand to the generation and that’s not going to be met by lithium, it’s too expensive and you just need vast quantities to handle it.”

The thermal energy storage system (TESS) device stores electricity as thermal energy by heating and melting containers full of silicon at a cost estimated to be up to ten times cheaper than lithium batteries. The high latent heat capacity and melting temperature of silicon – 1414 degrees Celsius – make it ideal for the storage of large amounts of energy.

Dr Moriarty said a site had been chosen in South Australia for the first 10MWh system.

“The idea will be to position these things near industry or get industry to move near to the very big units because it will be able to offer very clean, cheap heat,” he said. “We don’t have any dirty emissions like you do from gas or coal so basically the heat comes out as hot air and can be used for all sorts of things. Also, you can keep using the silicon, it’s pretty much unlimited.”

The company, previously known as Latent Heat Storage, has been developing the technology for the past decade in partnership with Adelaide-based engineering consultancy ammjohn, and the University of Adelaide. It aims to initially assemble the units at the Tonsley Innovation Hub in Adelaide and have its first 10MWh system operating by mid-year.

“Then we want to demonstrate the impact of one of our bigger units at a grid level so the search is on right now for a suitable site – preferably a wind farm,” Dr Moriarty said. “The plan is that we will then scale it up with further modules to something like 2-3 gigawatts of energy because that would enable you to store several days output and feed it back to the grid as required.

“As far as the future goes, it would be nice to keep the manufacture of these in South Australia, or at least the assembly of them, but it will depend on the sorts of deals we end up doing around the world. I can see possibly several assembly sites – one in Europe and one in North America – but it remains to be seen.

“One of the things we will be cautious about is retaining control of the intellectual property but at the same time we want to get it into production quickly because we want to stay ahead of any potential competitors.”

South Australia leads the nation in the uptake of wind energy and rooftop solar with renewable sources accounting for more than 40% of the electricity generated in the state. However, the intermittent nature of renewable energy has been the cause of intense debate in Australia in recent months.

“I think we’re in the ideal place in South Australia because there’s a demonstrable need here,” Dr Moriarty said. “We have a huge amount of renewable energy being wasted because they can’t match wind generation with the need.

“If we can demonstrate we can do that and do it cheaply then it’s going to change a lot of the economics and the reliability.”