Melbourne’s Fusion Energy leads charge to develop iron flow battery technology to store clean energy

In a major coup, an Australian company has secured the global intellectual property rights for an environmentally-friendly iron flow battery which is infinitely scalable.

Photo of Chief Revenue Officer of Fusion Energy Group, Geoff Bentley with Fusion Energy Group, Chief Executive Officer, Nathaniel Allen at their office in Melbourne on Tuesday 11 March 2023. Photo Luis Enrique Ascui

An Australian company has secured the global intellectual property rights for an iron flow battery which is infinitely scalable, amid the race to find cheap, efficient, environmentally sustainable ways to store renewable energy.

Melbourne-based Fusion Energy has partnered with US-based electrochemist Bob Savinell, who has adapted a prototype he first developed in the early 1980s.

NASA first invented a flow battery in response to the energy crisis of the 1970s and Savinell — now a professor at Case Western Reserve University in Ohio — came up with a model that uses iron.

Compared with other elements used in the manufacture of batteries, such as titanium, vanadium or the lithium that powers most phones and laptops, iron is abundant, cheap, and generally less environmentally destructive to mine.

Professor Savinell’s original prototype had some technical problems relating to corrosion, and amid the ascendancy of cheap, reliable fossil fuels as the energy crisis ended, it failed to get off the ground.

Attention has in recent years returned to the potential flow batteries have to play in storing renewable energy, with Oregon-based company ESS listing on the New York stock exchange in 2021, having developed a battery which lasts 12 hours, and is cheaper than lithium.

Another start-up — Boston based Form Energy — claims to have developed an iron-air battery which lasts 100 hours and is 10 times cheaper than Lithium.

Professor Savinell’s new model — set to be trialled at three Australian and three US industrial and rural sites this year — is infinitely scalable.

“The difference between our iron flow model and previous models is that the storage is decoupled from the battery, so if I want more storage, I just add another tank for it to flow through,” Fusion Energy chief revenue officer Geoff Bentley told The Australian.

“No other battery in the world works like this, and they’re mobile, you can put them in shipping containers and move them around,” Mr Bentley said.

The batteries use iron chloride, carbon and water, stored in cubic metre-sized tanks.

They consist of positive and negative solutions in separate tanks, which are pumped into half cells where they come into close contact but are kept separate via a membrane, which allows the electrons to move from one tank to the other during charging, effectively storing the energy.

Fusion Energy estimates the system can store energy for as little as $50 per kilowatt hour, and last at least 25 years, using 100 per cent recyclable materials.

The company currently specialises in delivering and maintaining critical infrastructure services such as uninterruptable power supplies and cooling, security and fire alarm systems.

Mr Bentley said the iron flow battery technology had the potential to significantly disrupt the global energy market.

“This will be an absolute game-changer. It will be able to power entire suburbs, and allow major manufacturers to remove themselves from the grid,” he said.

Competition is ramping up to establish the cheapest and most efficient modes of storing renewable energy, with Australia’s first large-scale sodium-sulphur battery installed earlier this month at a mine southeast of Kalgoorlie.