Leak detection in hydrogen distribution stations

How AI and acoustics contribute to the safety of hydrogen stations

Hydrogen differs from other gases in several ways, making it easier or more difficult to control the risks associated with it:

  • It leaks easily : the element with the smallest atom in the universe, low viscosity and high permeability, hydrogen easily leaks out of any container.
  • It damages metals and alloys: hydrogen embrittlement and attack can eventually cause equipment to leak or break.
  • It is extremely flammable: its minimum ignition energy in air (20 µJ) is more than 10 times lower than that of propane or petrol. This energy can be provided by simple electrostatic discharges from the human body. In pure-oxygen environments (which is the case with electrolysers), the energy needed is just 3 μJ.
  • Hydrogen burns with a flame that is nearly invisible in daylight, complicating emergency efforts. However, its low radiant heat means that the risk of flame spread induced by thermal effect due to radiant heat is limited.
  • It is highly explosive: with a volume percentage of between 4% and 75% in air, hydrogen is 10 times more explosive than propane. Because it burns seven times faster than propane, it has a higher detonation rate. The shock wave generated by a hydrogen explosion depends on the geometry of the containment structure, the ignition energy and the mixture with the oxidant (i.e., oxygen).

The recent development of the hydrogen sector and the installation of distribution stations, increasingly numerous and close to cities and roads, makes it necessary to strengthen leak detection strategies. In this case, since the stations are outdoors, acoustic sensors such as those developed by Wavely are a perfect solution.