An Australian start-up says it has invented a new super-efficient type of electrolyser that uses plasma, the fourth state of matter, to reduce the cost of green hydrogen by a factor of three.

Melbourne-based Hydrogen Systems Australia (HSA) says that today’s PEM (proton exchange membrane) electrolysers produce hydrogen at a levelised cost of about $5-7 per kilogram, while its new plasma electrolysers would produce H2 for $2/kg by 2024 (based on a power price of $35/MWh when operating for 12 hours a day) — and could go even lower after that.

Part of the cost savings will be due to the plasma electrolyser itself costing 90% less than PEM machines at current prices, with the rest coming from improved efficiency.

Understandably, HSA is keeping the details of its technology close to its chest, but executive director Brian Power tells Recharge that it works by using electrical power inside a plasma chamber at certain frequencies that elicit favourable responses from the hydrogen and oxygen atoms in water — a process that he says requires much less power than standard PEM or alkaline electrolysers.

“We’re letting the frequencies do all the work, whereas [a standard electrolyser] lets the electricity do all the work,” he says.

HSA has patented the technology and is currently fine-tuning the technology in the lab, with a view to completing testing by Christmas and starting limited production of small-scale electrolysers by 2024.

Brian Power, executive director of Hydrogen Systems Australia. Photo: HSA

The company has no intentions of building the kind of gigawatt-scale electrolyser factories that market leaders Nel and ITM Power are currently constructing. Instead, it wants to license its technology to existing electrolyser maker, who can then build multi-megawatt versions of the machines in their gigafactories.

HSA will meanwhile produce a small amount of 150kW electrolysers — far smaller than the 5MW machines currently on the market — that can be used to create off-grid baseload renewable energy systems.

“Our needs out here [in Australia], we think, will be more small-scale systems where you’ve got a solar array and a battery and a fuel cell on a [holiday] resort or running a small [remote] village and making the power where you consume it,” says Power.

“We’ve got two objectives,” adds Scott Podmore, HSA’s head of content. “One is small to medium scale… but the other is the licensing of this new technology, which could pretty well change the way the world creates hydrogen. It's a game changer. It's a serious game changer.”

Power explains: “Most of the big boys are here [in Australia] whether it’s [electrolyser makers] Plug Power, [Cummins-owned] Hydrogenics or Nel, they’re all battling it out for the major plays. We would license it to all three of them. They’d be mad not to if [our technology] is going to be more efficient.”

Talks have already begun with “bigger companies, bigger boys who are knocking on the door wanting to know what’s going on”, says Podmore.

Power, an engineer with a background in designing plasma systems for the nanotech industry, explains that although the likes of Nel are building their own gigafactories, it would not be hard to re-tool them for plasma electrolysers as only about 10% of the manufacturing process would need to be changed.

“They've all got pumps. They've all got manifolds. They've all got pressurisation. A lot of the fundamental engineering is the same. It's just what's going on for us inside the chamber is going to be different. The outer housings and the pump will be the same,” he says.

HSA — which has been so far been funded by individuals and the company founders — is now seeking to raise A$10m ($7.5m) of funding to help pay for ongoing testing and new production facilities.