Innovative pressure reducer: from compressed hydrogen to heat pumps
Hydrogen from renewable resources is essential for the energy transition and forms the basis of low-emission energy systems. Due to its low density under ambient conditions, hydrogen is typically compressed to make its storage and transport more economical. The energy required to compress hydrogen amounts to up to 15 percent of its calorific value and is usually not recovered. As such, DLR is developing a technology that harnesses this energy in the form of a heat pump or refrigeration system, enabling efficiency gains of between 7 and 30 percent.
Generating cold in mobile applications
DLR is also investigating how this technology can be integrated into transport applications such as lorries, buses, or rail vehicles. Validated simulations conducted by DLR show an increase in range of up to 20 percent. Following a successful demonstration at Technology Readiness Level 4 (TRL 4) with 1 kW cooling capacity in the laboratory, the next step is to demonstrate the technology at TRL 6 in a rail vehicle for the 5 kW cooling power class by 2026.
Heat pumps for stationary industrial plants or neighbourhoods
In principle, the integration of this technology into any process is possible where the pressure ratio between hydrogen supply and hydrogen utilisation is greater than five. The efficiency improvements achievable with DLR’s technology when utilising hydrogen – a valuable energy resource – can be decisive in transitioning a process to hydrogen.
Links:
German Aerospace Center (DLR)
Institute of Engineering Thermodynamics
E-Mail contact-dlr@DLR.de
ystem for 5 kWcooling for integration into a rail vehicle
Demonstration of DLR technology for air conditioning of fuel cell vehicles for 1 kWcooling
Credits: ©DLR