Safely on the move at high pressure

As part of the HY.City.Bremerhaven project initiated by GP JOULE and Greenfuels, surplus electricity in Bremerhaven is being converted into CO2-neutral hydrogen and is being made available to the transport sector, among others. For this purpose, two special trailers developed by GP JOULE, each equipped with four high-pressure vessels, are filled fully automatically with the highly flammable gas and compressed up to 380 bar. Hydrogen in conjunction with oxygen is a highly explosive gas mixture: both filling and emptying the special high-pressure vessels poses potential hazards. GP JOULE relies on the safe, industry-proven small controller PNOZmulti 2 from Pilz: it reliably monitors the transfer process with failsafe analogue value processing.

The challenge was to ensure that the process of filling and emptying the trailers at filling stations and other collection points was standardised, simple and safe. The safety controller was not to be at the stations, but on board the trailer. There were no standard solutions. Consequently, GP JOULE and Pilz worked together to develop a new and unique mobile safety solution, based on the safe small controller PNOZmulti 2. The system comprises the base unit PNOZ m B1 with multiple safe analogue input modules and one safe relay output module. PNOZmulti 2 uses failsafe analogue value processing to monitor compliance with relevant parameters and critical limit values for pressure and temperature, as well as the loading and unloading speed. The "Safe ramp monitoring" block integrated within the PNOZmulti Configurator enables precise limit value setting with dynamic limit value monitoring at safety level SIL 2.

• Reliable monitoring of the transfer processes and fast error reaction
• High precision and adaptability of the safety solution
• Compact and modular solution for safe, efficient processes

For GP JOULE, based in Reußenköge (North Frisia), hydrogen is the "battery of the energy transition", with development potential that is far from being fully utilised. Founded in 2009, the company sees itself as an integrated energy supplier, which develops and implements sustainable and renewable energy solutions. GP JOULE employs around 1,000 staff and is active in various renewable energy sectors, such as solar and wind power, heat, mobility and, in particular, hydrogen.