Case study: Testing liquid hydrogen systems in demanding applications

Background and market developments

With the transition to renewable energies and the need to transport hydrogen efficiently, liquid hydrogen is increasingly coming into focus. As industries seek solutions that combine high energy density with safe handling, LH2 is emerging as a key enabler. This shift brings new technical and safety questions that cannot be reliably answered without controlled testing environments. Key emerging markets and developments for LH2 include heavy-duty transport and aviation in particular, where innovation pressure and safety standards are exceptionally high.

Manufacturers of storage systems and components can rely on the expertise and support of Kiwa Energy Technology (ET) to successfully achieve their development goals. By testing early and thoroughly, they avoid later redesigns and ensure their systems behave predictably in demanding applications.

The technical situation and expertise of Kiwa ET

There are only a few independent laboratories worldwide with an LH2 testing infrastructure comparable to that of Kiwa Energy Technology. This scarcity exists because LH2 handling requires rare permits, cryogenic equipment  and high safety standards.

What makes Kiwa unique:

• Unique testing environment: LH2 behaves fundamentally differently from gaseous hydrogen; testing with the actual medium is essential to understand real-world performance.
• Independence and confidentiality: As an independent testing laboratory, Kiwa guarantees customer confidentiality (certified according to ISO 27001, TISAX). Independent testing ensures unbiased results, which is critical for regulatory acceptance.
• Shorter development times for our customers: Streamlined testing workflows shorten the test duration and prevent long waiting times typically seen in LH2 infrastructure
• Expertise of experienced employees: LH2 testing demands specialist knowledge to be able to deal with unexpected behavior of the test specimens during the tests.
• Explosion-protected laboratory environments for testing with the original medium (LH2): These measures enable malfunctions or leaks occurring during the tests to be safety controlled.

In order to comply with regulatory and safety-related requirements, appropriate operating permits are necessary, as well as qualified specialists who work under the strictest safety standards. This ensures that LH2 testing can be conducted without risk to personnel or equipment.

Components and systems

Kiwa supports the development of hydrogen storage systems. This typically begins early in the development chain. Testing starts at component level because individual failures often originate in small parts rather than the full system.

These tests focus on tanks, sensors and materials. Other components such as pumps, valves, level probes and heat exchangers are also tested. Each of these plays a crucial role in the system’s safety and performance; validating them individually prevents integrated failures later.

The test series with storage systems are designed to systematically check all functions of a tank system and characterize its properties. The functions that are tested include:

• Fueling and refueling
• Long term parking, dormancy, boil-off control
• Defueling, operation, fuel supply
• level metering
• pressure relief function

System monitoring

These functions cover the complete use cycle of a storage system, from filling to operation to standby, ensuring reliable behavior in all phases.

Special challenge – supercritical hydrogen

In general, handling LH2 poses particular challenges. This includes extremely low temperatures, rapid phase transitions and special safety considerations. In addition, we have experience in handling supercooled and supercritical hydrogen (sLH2). This expertise is needed because some applications require hydrogen beyond standard liquid conditions, where physics and system behavior become even more complex.

The testing and certification process

The test facilities and test benches can be flexibly adapted to the specific project requirements. This flexibility is necessary because LH2 systems vary greatly in size, geometry and pressure levels. Kiwa uses a flexible modular system of components for preparation and adaptation, allowing quick adjustments and efficient test execution.