Introduction to Hydrogen Testing

Testing hydrogen engines and fuel cells requires a more considered setup than testing traditional internal combustion engines.

Firstly, this largely stems from dealing with an explosive gas rather than liquid fuel.

Consequently, operators must control hydrogen safely and prevent its escape into the test cell environment.

Furthermore, it is important to consider and plan for other factors like sourcing and storing hydrogen.

Moreover, this guide focuses on upgrading an existing test cell, which is a more economical and practical approach than constructing a new one.

Finally, you will learn the fundamentals of our 7 Stage Hydrogen Test Cell Upgrade Blueprint, understand the scope of the work required, and comprehend its implications for your wider facility.

Table of Contents

Benefits of Upgrading

New/Additional Capability

Upgrading an existing test cell not only enables it to test Hydrogen Engines and Fuel Cells but also allows it to retain its capability to test regular fuel engines.

Additionally, the upgrade enhances the test cell’s capability without compromising any of its core functionality.

Specifically, the main improvements include safety monitoring and control of the whole environment, specific air handling, and ventilation solutions.

Ultimately, a combination of facility services improvements, hardware, and software accomplishes this.

More Economic

It is much more cost effective to upgrade an existing test cell than it is to build a whole new one.

This is because most of the test cell components will be upgraded, and some of the ventilation structures will be adapted, 


An engine test cell can be upgraded if it meets some basic criteria:

Hydrogen Testing Considerations

Understanding Hydrogen Fuel Properties

Hydrogen has different combustion behaviour compared to conventional fuels. 

A safe test cell requires adaptations in the design to facilitate the introduction of combustable gas.

Upgrading Powertrain Test Cells

The project should include the upgrade of powertrain test cells for running with hydrogen fuel systems. 

The initial investment in hydrogen facilities can be matched through plans to upgrade further test cells to be capable of hydrogen-based powertrain testing at higher power levels.

Ensuring Safety

When dealing with hydrogen, safety is paramount.

The overall safety of the test cell as well as the infrastructure and the storage of hydrogen should be well planned in.

Also engaging with a safety consultant for design approval and installation sign off should be a priority.

Conducting Tests

Various tests such safety, reliability, and durability tests should be conducted once the upgrade is complete.

Other key tests include cell sealing, negative cell pressure, sensor/detector activation, and emergency matrix functionality.

Switching to Hydrogen Testing

It is going to take multiple solutions to decarbonise transport.

There is definitely a role for hydrogen to play in supporting the powertrain requirements of larger vehicles. 

Upgrading engine test cells for hydrogen engine and fuel cell testing is a significant step towards cleaner mobility.

The Hydrogen Upgrade Blueprint

At Sierra CP, we use a 7 stage blueprint when upgrading a test cell for Hydrogen testing. 

Here is a snapshot of the blueprint:


Initially, as with any bespoke project like a Hydrogen Test Cell Upgrade, a detailed assessment of the space, adjoining areas, and existing hardware is crucial as part of the planning.

Subsequently, we would typically carry out a full survey and then follow it with a development session to determine the full hardware and software blueprint for your upgrade.

Safety Controller

We have written our own safety controller code which focuses on the key aspects of safe working practices when dealing with Hydrogen.

The safety system relies on specific sensors and detectors for monitoring H2 levels within the test cell at various locations.

There are also inputs from the sub systems such as ventilation fans and the host control system.

Risk Mitigation

To anticipate, mitigate, and manage potential failures in the system it’s essential to have the correct strategies and procedures in place.

This is derived from a safety matrix and comprises a series of activities including reliability modelling and failure reporting systems.

An inherently failure-free design is the goal of these activities. 

The primary objective of the reliability program will be to ensure that designs are inherently robust in relation to operational processes and to the environmental conditions of storage, maintenance, and operation, throughout the life of the system.

Ventilation, Exhaust & Purge

To meet the new requirements for testing H₂, one must implement subtle but important changes to convert a conventional test cell into an H₂ compatible design.

One must consider and specify elements of the test cell such as air flow direction, extraction points, exhaust gas removal, sensor location, and volumetric flow capacities according to the fuel flow expectations.

One should determine the air supply to devices within the test cell and decide whether items should be sealed or open.

Generally, one uses ATEX fans throughout, and sets the flow rate and routing strategy based on the current H₂ levels detected.

Download The Blueprint

This Hydrogen Test Cell Upgrade Blueprint contains all the information you need to carry out your own pre-assessment.

This can lead to a better understanding of the project within your team, and when you start the consultation process all the relevant information will be at hand.

The plan is free to download, and you will receive some follow up emails from us to guide you further. 

There’s no pressure to set up a meeting, until you are ready to do so.