By: Jim Watkins, European Business Development Director

At Hyvolution Paris, the electrolyzer conversation is shifting. Stack performance still matters, but it’s no longer the whole story. As projects move from equipment purchases to long-lived assets, developers and financiers are looking for something more specific: proof that electrolyzers can be operated reliably, flexibly and profitably under real-world market conditions.

That was the focus of the “Electrolyzer as a System: Successful Operations” panel, moderated by Silke Frank, Managing Director at Hydrogen Moves. The speakers were Mirela Atanasiu, Head of Unit Operations and Communication at the Clean Hydrogen Partnership; Benoît Barrière, Head of Technology Integration at John Cockerill Hydrogen; and Hamutal Ben Bassat, Cleantech Partnerships Manager at the CFU Partnership Hub.

From a single key performance indicator (KPI) to the number investors underwrite. The panel opened with a question that quickly became a proxy for financing: if you had to pick one operational KPI that makes an electrolyzer project bankable today, what is it?

Efficiency came up immediately. Electricity is typically the dominant operating cost in electrolytic hydrogen (H₂), so reducing specific energy consumption flows straight into cost per kilogram (kg). But the discussion moved fast from efficiency as a standalone metric to a more finance-aligned view: the KPI that matters most is the one that combines all the operational realities into a single economic outcome.

In practice, that means levelized cost of H₂ (LCOH). LCOH captures efficiency, but it also forces attention onto capital expenditure (CAPEX), operating expenditure (OPEX), electricity price and the plant’s ability to stay online. A project can have strong nameplate specs and still fail commercially if availability, ramping constraints, or degradation undermine real production.

Availability is the KPI behind the KPI. If LCOH is the headline number, availability is one of the most sensitive drivers behind it. The point wasn’t just maintenance uptime. It was the operational ability to produce within spec, avoid unplanned outages, and sustain performance over time. Availability is where engineering meets economics: every percentage point lost can erode the project’s margin, and every instability event increases perceived risk for lenders and offtakers.

Operating between two markets. A second theme was that electrolyzer operations sit between two markets, and both matter.

On the input side is power. Projects may rely on dedicated renewables, the grid, or a hybrid approach. Operators increasingly have to manage price volatility and, in parts of Europe, periods of very low or even negative pricing.

On the output side is H₂ demand. Offtakers impose constraints on purity, pressure, and delivery cadence. Storage limits can cap production. And sometimes the customer simply doesn’t want H₂ at that moment, forcing curtailment or operational re-optimization.

The operational challenge, then, is managing both interfaces simultaneously: making smart dispatch choices on electricity while meeting H₂ delivery requirements without sacrificing equipment life.

Flexibility is moving into the business model. Flexibility was treated as more than a technical feature. Electrolyzers are increasingly being evaluated as controllable load that can support grid stability, with compensation mechanisms emerging in some markets. The requirement is proof of fast, reliable curtailment and ramp behavior, and proof that flexible operation doesn’t destroy durability.

Data, controls and trust. Finally, the panel aligned on a core enabler: instrumentation and data. If projects are going to be financed as assets, they need operating evidence. That means system-level monitoring, component-level diagnostics, model calibration for digital twins, and secure remote access. Cybersecurity isn’t a side topic here. If stakeholders don’t trust the data plane, they won’t trust the operating model.

The takeaway was straightforward: the sector isn’t just selling electrolyzers anymore. It’s selling an operating system. And the projects that win financing will be the ones that can demonstrate low LCOH through availability, flexibility, and validated performance in the field.