Power to Hydrogen (P2H2) and Repsol say a rigorous pilot of P2H2’s anion exchange membrane (AEM) electrolyzer technology has delivered results that could strengthen the case for a lower-cost route to large-scale green hydrogen.

 

The pilot, conducted through Repsol’s All4Zero industrial innovation hub, subjected P2H2’s commercial-scale AEM stack to more than 1,250 hours of parametric and durability testing, including extensive operation under simulated renewable-power load profiles.

 

The system met or exceeded key targets for efficiency, flexibility and durability, according to the companies. P2H2 says the results point to system lifetimes exceeding 50,000 hours — potentially 5–10 times current AEM industry benchmarks.

 

“This pilot proves what we’ve long believed: that AEM electrolysis can deliver PEM-like performance at a fundamentally lower cost structure,” said Paul Matter, Founder and CEO of Power to Hydrogen. “With Repsol’s rigorous testing framework and real-world operating conditions, we’ve demonstrated the durability and efficiency that the market has been waiting to see from AEM. This is commercial-scale hardware, stress-tested under the conditions that matter to industrial buyers.”

 

Using Repsol-specific inputs and the U.S. Department of Energy’s H2A-Lite analysis framework, P2H2 projects a levelized cost of hydrogen of approximately €3.86/kg — about 16% below incumbent electrolyzer technologies.

 

Under optimized renewable-energy scenarios using hybrid power purchase agreements, the company says costs could fall to approximately €2.82/kg, bringing the technology closer to what it describes as commercially decisive thresholds for industrial hydrogen adoption.

 

The pilot also targeted one of the biggest challenges facing renewable hydrogen projects: operating reliably as renewable power fluctuates.

 

The All4Zero testing protocol subjected the system to variable load profiles based on real operating conditions, repeated cycling between 40% and 100% load, and pressures ranging from 2 to 30 bar.

 

P2H2 says the technology’s fast dynamic response, combined with an iridium-free and PFAS-free materials pathway and low capital intensity, could offer industrial users greater operating flexibility while reducing exposure to critical-mineral constraints and regulatory risks associated with conventional PEM electrolysis.

 

The testing used P2H2’s commercial-scale cells in a five-cell short stack and produced several results the company says outperformed conventional PEM benchmarks:

 

Low degradation: Approximately 2 mV/kHr of irreversible degradation over 1,250 hours, with average cell voltage virtually unchanged between the start and end of testing. P2H2 says the results project system lifetimes beyond 50,000 hours.

 

High hydrogen purity: Direct-from-stack hydrogen purity reached up to 99.9% at 30 bar, with consistent performance across the 2–30 bar pressure range.

 

Dynamic operation: The stack demonstrated strong load-response performance under conditions designed to replicate real-world renewable-power operation.

 

Shutdown resilience: The system withstood unplanned shutdowns, including a facility power outage, and resumed testing without consequence.

 

“Through our All4Zero accelerator, Repsol is committed to identifying and validating the technologies that will be essential to decarbonizing industrial operations at scale,” said Berta Moreno, Senior Scientist at Repsol. “Power to Hydrogen’s results demonstrate meaningful progress toward the performance thresholds required for large-scale renewable hydrogen deployment.”

 

Next test is commercial scale-up.

 

The companies are now exploring a larger demonstration in the 500 kW-to-MW range, a key step toward commercial deployment.

 

The scale-up would also support Repsol’s target of developing 600–800 MW of renewable hydrogen capacity by 2030.

 

P2H2 is already deploying systems at this scale, including projects at the Port of Antwerp-Bruges in Belgium and with SINTEF in Norway.

 

The latest pilot gives AEM technology another significant data point in the race to make renewable hydrogen cheaper, more durable and better suited to the intermittent power supplies that will increasingly drive electrolyzer operations.