BP has led a $12.5m Series A funding round for Advanced Ionics, a Wisconsin-based start-up that has developed an electrolyser capable of producing hydrogen at a 30% higher efficiency than most technologies on the market.

The Symbion electrolyser is said to operate at extremely high efficiency, requiring less than 35kWh of electricity input per kilogramme of hydrogen when paired with an external heat source.

This compares to the 37.7kWh/kgH2 efficiency achieved by Bloom Energy’s solid-oxide electrolyser (SOE) in tests, one of the highest efficiencies on the market today.

The Symbion electrolyser is around 30% more efficient than alkaline and proton exchange membrane (PEM) electrolysers, generally considered the most mature commercially available technologies. These both require more than 50kWh/kgH2, although they generally work at lower temperatures.

Similar to SOEs, Advanced Ionics’ technology requires heat as well as electricity. However, the Symbion electrolyser can work at any temperature above 150°C, in contrast to many SOEs which need to run at 700-850°C or above.

The start-up’s CEO Chad Mason told Recharge last year that this opens up a much wider range of industrial processes that the electrolyser can be co-located with, particularly since the steam does not need to be “stepped up” in temperature and increase running costs.

Similarly, since the equipment is made with stainless steel and other low-cost materials, Mason suggested that the electrolyser will cost less than its PEM rivals, which use platinum group metals, and last longer than SOEs, which require brittle ceramics as the solid electrolyte.

Advanced Ionics is currently testing its technology with Spanish oil company Repsol. And BP has said it will also explore deploying the Symbion electrolyser at pilot scale.

“Advanced Ionics’ technology has the potential to drive down cost and disrupt the hydrogen market,” said Gareth Burns, vice-president of BP’s venture capital arm.

“BP has a global portfolio of hydrogen projects, and as the world transitions to a net-zero future, it’s important to us to be investing in these technologies and advance the track to deploying green hydrogen. We look forward to working with Advanced Ionics on the next stage of its growth.”

Other new investors in the latest funding round include Clean Energy Ventures, Mitsubishi Heavy Industries, and GVP Climate, an investment firm that focuses on early-stage clean technology.