Crowcon’s Ben Jones says operators converting gas storage to hydrogen must check detectors, rethink placement and choose sensors suited to hydrogen.
(P&GJ) — Operators converting natural gas storage sites to hydrogen need to make sure their gas detection systems can detect hydrogen, according to Ben Jones, head of product at gas detection company Crowcon.
The warning comes as Germany advances underground hydrogen storage. EWE has completed gas-tightness tests on a converted natural gas cavern well in Huntorf, with plans to store about 1,587 short tons (1,440 metric tons) of hydrogen by 2028.
Jones identified three risks.
Infrared detectors cannot detect hydrogen. Many natural gas facilities use infrared detectors to monitor methane and other hydrocarbons, but hydrogen molecules do not absorb infrared light at the wavelengths these sensors measure. “This means equipment that has reliably detected methane for years could completely miss a hydrogen leak, even while operating exactly as designed,” Jones said. Because hydrogen is odorless and invisible, workers cannot rely on their senses to notice a leak.
Detector placement may need to change. Wellheads, compressors, valves and connecting pipework are all potential leak points. Hydrogen is much lighter than air and can accumulate at higher points in enclosed or poorly ventilated spaces, so detector locations suited to natural gas may not provide coverage for hydrogen. Hydrogen can become flammable in air at concentrations as low as 4% by volume, and alarm points need to reflect that, Jones said.
Sensor technology matters over the long term. Catalytic sensors are widely used to detect hydrogen, but some contaminants can reduce their sensitivity over time, so they need regular bump testing and calibration. Jones said newer micro-electro-mechanical systems sensors can detect hydrogen alongside other flammable gases without the same susceptibility to poisoning and do not require routine calibration, though no single technology suits every environment.
“A facility may be ready to store hydrogen, but that doesn’t automatically mean its existing gas detection systems are ready to monitor it,” Jones said.
