Paul Matter has spent seven years arguing that the cheapest way to make green hydrogen is to stop using platinum. On August 11, his company shipped the first machine that tests the argument outside a laboratory.
Power to Hydrogen, the Columbus, Ohio company Matter leads, delivered a half-megawatt electrolyzer to the Port of Antwerp-Bruges. The unit is the first industrial-scale system built on anion exchange membrane (AEM) stacks, and the first AEM electrolyzer designed to run inside a working European port.
A 1,250-hour pilot with Repsol projects a stack lifetime beyond 50,000 hours, which the company says is 5 to 10 times current AEM benchmarks, at hydrogen purity up to 99.9%.
The claim that matters for investors is cost: up to 65% lower capex than PEM electrolyzers, because the stack swaps iridium and platinum for steel and nickel.
Electrolysis splits water into hydrogen and oxygen with electricity. The commercial leader, proton exchange membrane (PEM), is fast and compact, but its catalysts lean on iridium and platinum, among the scarcest metals on earth. The cheaper alternative, alkaline electrolysis, runs on nickel and steel but responds too slowly to track the output of a wind farm.
AEM tries to combine the two: alkaline-grade materials with PEM-grade speed. Its membrane conducts hydroxide ions instead of protons, which lets inexpensive metals carry the reaction.
TIMELINE: Power to Hydrogen, lab to industrial port
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2019 ─────── 2024 ─────── 2025 ─────── 2026 ─────── 2026
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Founded Utility $20M Antwerp Repsol
Columbus demo Series A delivery pilot
Company announcements and press releases, 2019 to 2026
Why iridium was the bottleneck
A PEM stack is a precision instrument. Its iridium coating must survive years of voltage cycling, and iridium trades above $150,000 per kilogram on thin supply. Platinum adds a second rare-metal bill. Those materials, not the housing or the power electronics, set much of the cost floor.
The company's hybrid design drops noble metals from the catalyst layer and replaces them with nickel and steel. The company puts the saving at up to 65% on capital cost against a comparable PEM system.
That is the bet.
Claimed capital-cost reduction
Power to Hydrogen's estimate for its AEM stack against a comparable PEM electrolyzer · Power to Hydrogen, 2026
That number deserves scrutiny. A capex comparison depends on what a buyer counts and on the PEM benchmark chosen. So far the figure is a company estimate, published alongside partner projects rather than audited by a third party. The Antwerp installation is meant to close part of that gap, because P2H2 says the port project will produce a repeatable, validated configuration.
The pilot that had to hold
Durability, not cost, is where AEM has stalled. Membranes degrade, and a stack that lasts 8,000 hours cannot justify a utility's capital. The company ran a 1,250-hour test with Repsol at the Spanish energy company's All4Zero innovation hub, using commercial-scale cells inside a five-cell short stack.
The result: roughly 2 millivolts of irreversible degradation per 1,000 hours, hydrogen purity up to 99.9% at 30 bar of pressure, and stable output across a 40% to 100% load range. Projected onto a full stack, those figures imply a life beyond 50,000 hours.
This pilot proves what we've long believed: that AEM electrolysis can deliver PEM-like performance at a fundamentally lower cost structure.— Paul Matter, CEO, Power to Hydrogen
Repsol senior scientist Berta Moreno framed the outcome as clearing a threshold rather than winning a race. The two companies are now weighing a larger demonstration in the 500 kW to megawatt range, part of Repsol's target of 600 to 800 MW of renewable hydrogen capacity by 2030.
One port, then a production line
Antwerp is the reference plant. Holthausen, a regional industrial-gas supplier, will be the first offtaker, and P2H2 expects the site to earn commercial revenue from its first year. The M-Class unit is designed to scale to 25 MW, the size a refinery or steel mill actually buys.
A second order is already moving. SINTEF, the Norwegian research institute, bought a 0.5 MW system for its Tiller site, to be delivered in the fourth quarter of 2026. There the hydrogen feeds PYROCO2, an EU project that combines it with captured carbon dioxide to make acetone, a platform chemical used in solvents and plastics.
| Parameter | PEM | Alkaline | AEM |
|---|---|---|---|
| Precious-metal catalyst | ✗ iridium, platinum | ✔ none | ✔ none |
| Load-following response | ✔ fast | ◐ slow | ✔ fast |
| Materials cost | ✗ high | ✔ low | ✔ low |
| Commercial maturity | ✔ GW scale | ✔ GW scale | ◐ first industrial units |
As we wrote in August, the hydrogen supply chain is already being reshaped by cheaper catalyst discovery, and the electrolyzer is one node in it. The thesis is simpler: the stack, not the molecule's end use, is where the cost curve breaks first.
The turning points
Three moments track the shift from promise to product. In 2024, P2H2 signed the Antwerp pilot and ran a Phase I stack demonstration with four utilities: American Electric Power, EDP, E.ON, and Ireland's ESB. Those utility partners stayed. In March 2025 came a $20 million Series A, led by industrial investors including Air Liquide, MOL Switch, and Karpowership. An earlier $9.5 million round had already landed. The World Economic Forum named the company a Technology Pioneer in June 2026.
Each step added a partner who would notice if the hardware failed. That is the useful function of a port, a utility, and a research institute on the same reference list.
The case for AEM at industrial scale
+ A 50,000-hour projection, if it holds, clears utility hurdle rates
+ Two commercial orders before the first site is even commissioned
Confirmation criteria: Antwerp runs a full winter on variable power at the promised capex.
The case against
− The 65% capex gap is self-reported, not third-party audited
− PEM costs keep falling as iridium loadings drop
Disconfirmation criteria: stacking losses or membrane wear at the port scale faster than the pilot curve.
What has to be true now
The investment case rests on three tests. The first is durability at megawatt scale, where membrane area grows and failure modes multiply. The second is manufacturing repeatability, the difference between one validated stack and a line that ships hundreds. The third is demand: green hydrogen projects have slipped before, and an electrolyzer is only worth its capex if a buyer needs molecules.
Incumbents are not standing still. PEM prices keep falling as iridium loadings thin out, and alkaline suppliers keep improving response times. P2H2's edge narrows if either catches up before its own cost curve bends.
The Antwerp commissioning, due this month, is the first public data point. A stack that runs through a winter of variable power at something close to the promised cost would turn a seven-year argument into an order book.