Research into the safe use of liquid hydrogen

With the target of net zero carbon emissions by 2050 in the UK, HSE scientists and engineers are studying alternatives to fossil fuels, including using hydrogen as a 'vector' that can be used to store energy produced in low-carbon ways.

With a greater energy density than the gaseous form, liquid hydrogen (LH2) could form part of the UK's energy strategy in the future.

In order to enable the safe and widespread adoption of LH2 as an energy storage and transportation method, the PresLHy consortium has studied several high-risk and poorly understood phenomena relating to the substance.

How is HSE helping?

Scientists and engineers at HSE's Science and Research Centre conducted a series of 57 full-scale experiments to investigate the behaviour of LH2 in an accidental spillage scenario.

These investigations focused on three main aspects: the release and dispersion characteristics of a spill, the propensity for a spill to generate an electrostatic charge capable of igniting a hydrogen cloud, and the effect of congestion on an ignited cloud of hydrogen.

A limited number of experiments were also designed to study the effect that common emergency response techniques have on LH2 spills. Both a sprinkler system and fire hose were deployed on a pool of LH2 to investigate the potential for rapid boiling.

What did we learn?

The experimental series yielded valuable data including direct measurements of the mass flow rate of the LH2 liquid hydrogen in the pipework, in what could be a world first.

This data will help to inform potential accident prevention and mitigation measures as members of the PresLHy consortium continue to develop engineering safety tools and a liquid hydrogen handbook that will enable industry to adopt the technology with more confidence.

HSE, (2021). Sixth Annual Science Review, pp.49-50.