HRS – Hydrogen Refueling Stations
In general, hydrogen filling stations can be divided into off-site stations (hydrogen supplied from an external source) and on-site stations where H2 is produced directly at the station.
By mid 2020, more than 400 hydrogen refueling stations were in operation worldwide, thereof in
- Japan 114
- Germany 84
- USA 44 (t/o 42 in California)
- South Korea 33
- China 27
with national strategies in place to widely expand the HRS network.
HRS locations can be found on these webpages:
Main components of a hydrogen refueling station comprise of
- adequately sized storage facilities for hydrogen
- compressors which bring the hydrogen to the desired gas pressure level
- a pre-cooling system
- dispensers for delivering the fuel
Hydrogen storage tanks
Low-pressure storage tank: between 20 and 200 bar (in future up to 500 bar); the hydrogen from the low-pressure storage tank can be transferred via a compressor to the high-pressure storage tank.
Medium- and high-pressure storage tanks: with pressure stages of 200 to 450 bar and 800 to 1,000 bar respectively, used to refuel the FC vehicle.
Hydrogen compression is required to overcome the pressure difference between storage (between 50 and 200 bar) and refueling (up to 1000 bar). A number of different compressor types can be used to achieve the necessary compression, depending on the design of the refueling station (capacity utilization, energy consumption, cost-effectiveness, etc.).
Since hydrogen is compressed during refueling, it heats up. The SAE J2601 fueling protocol, which covers hydrogen vehicle refueling, aims to ensure that a vehicle’s hydrogen tank does not heat up above 85°C even during fast refueling. Precooling is typically necessary to stay within the limits (overpressure/overheat) of the vehicle’s fuel storage system. For 700 bar refueling hydrogen is generally precooled to –40°C. Higher precooling temperatures are possible, but may lead to longer refuelling times, which are targeted to stay below 5 minutes.
The dispenser delivers the compressed hydrogen into the vehicle’s pressure tank via a nozzle. It is designed for the pressure of the hydrogen tank, i.e. 700 bar (70 Mpa) or 350 bar (35 Mpa) of which the latter one gets less important.