The goal of the TU Delft Hydro Motion Team is as ambitious as it is inspiring: to design, build, test, and race a fully functioning boat powered by liquid hydrogen, all within one year, and to compete at the Monaco Energy Boat Challenge 2025. But beyond the competition itself, the team’s mission reaches further. By proving that a boat can operate successfully on liquid hydrogen, they aim to spark broader innovation across the maritime sector and demonstrate hydrogen’s potential as a clean, scalable alternative to fossil fuels.

This project builds on the team’s past successes with compressed hydrogen, already a proven, zero-emission marine fuel. But as the team pushes for longer range and greater onboard efficiency, storage volume and energy density become the next major challenges. To solve this, the team chose to work with liquid hydrogen. With a volumetric energy density three times higher than compressed hydrogen at 350 bar, liquid hydrogen offers a powerful solution for saving space and extending endurance, key requirements in performance vessels.

But storing and using liquid hydrogen introduces challenges. The fuel must be kept at -253°C, requiring insulated cryogenic tanks. The team addresses this with a custom double-walled, vacuum-insulated carbon-fibber tank system, limiting heat ingress to just 7 watts, equivalent to a small LED bulb. To avoid wasting energy, waste heat from the fuel cell is used to bring hydrogen up to the required ~20°C operating temperature before reaching the fuel cell.

These trade-offs (boil-off rates, tank volume, storage weight, and onboard vaporization) are exactly the kinds of real-world constraints this project is designed to explore. And while Mira is a compact, foiling boat, the broader engineering question remains: could a system like this scale to larger vessels, such as ferries? That is the kind of thinking Alicat is excited to support with partners who are pushing the boundaries of what is possible.

Unter Mira’s hydrogen system, hydrogen is stored as a cryogenic liquid. Before reaching the fuel cell, it passes through a vaporizer, transitioning into gas at ambient temperature. This phase is critical: delivering gas at the right pressure and flow requires stable regulation, fast feedback, and precise control.

To meet this need, the team integrated the Alicat MCRQ mass flow controller immediately downstream of the vaporizer. This device manages the mass flow of hydrogen gas into the fuel cell and enables:

• Delivers stable and precise feed pressure to the fuel cell.
• Measures hydrogen consumption through real-time mass flow monitoring
• Monitors pressure and temperature to help prevent fuel cell issues like dehydration or fuel starvation.
• Supports test validation und real-world performance optimization.

Compact, ATEX Zone 2 certified, and designed for fast system response, the MCRQ integrates easily into the tight constraints of a race-ready vessel. Its role is vital during system development, helping the team collect data, tune parameters, and prepare for race-day performance. In short, it helps translate bold hydrogen engineering into operational reliability.

The Hydro Motion Team, together with our application engineers, selected the Alicat MCRQ series for its proven capability in low-flow hydrogen gas applications, offering a powerful combination of precision, speed, and safety. Key features that influenced the decision include:

• Flow range of 0–1.5 g/s, which translates to ±0.01 g/s uncertainty at a nominal 1 g/s flow, small enough to maintain consistent fuel cell output.
• 4–20 mA analog output, chosen specifically for its high-speed update rates (kHz range)
• ATEX Zone 2 IIC certification, requiring minimal additional safety infrastructure.
• Upstream valve position, enabling precise regulation of downstream feed pressure, supporting target values like the ~2.5 bar commonly seen in fuel cell stacks.
• ±1.0% accuracy of reading (or ±0.2% of full scale)

Together, these features provide the team with a robust, compact, and responsive solution, a key enabler of real-world testing and a step toward scalable, clean hydrogen propulsion.

The TU Delft team unveiled the boat, Mira, earlier this year and is now deep into the testing phase, preparing for the Monaco Energy Boat Challenge 2025.

As testing progresses, the team continues optimizing the integration between hydrogen storage, vaporization, and control systems. Alicat’s instrumentation plays a central role in capturing this performance data for analysis and refinement.

This partnership represents more than a technical contribution. It reflects our belief that sustainable innovation thrives where education, engineering, and real-world experimentation meet.

By supporting the Hydro Motion Team and their work on Mira, Alicat contributes to:

• Advancing liquid hydrogen fuel systems in marine transport
• Empowering hands-on engineering education
• Promoting practical low-emission propulsion technologies

We are honoured to be part of this project and proud to know that our instruments are helping to steer the future of clean maritime energy.

Together, we are not just measuring hydrogen. We are helping to Fuel the Future.