Refueling a vehicle with hydrogen is very simple. Whether it is a car, a bus, a truck or a forklift, you only have to take into account the pressure at which the filling must be carried out, since both the dispenser to be used and the various components that take part in it will depend on it. the operation
The nomenclature that has been standardized indicates two possibilities in the service stations open to the public that currently exist.
H35 corresponds to the filling pressure of 350 bar, or what is the same 35 MPa (where the identification number comes from). This pressure is mainly used in heavy vehicles, whether they are buses or transport trucks, since it allows the use of less heavy and more economical storage tanks by having more space on the vehicle chassis. Also both the storage and the use of hydrogen at this pressure turns out to be easier.
H70 corresponds to the pressure of 700bar, or 70MPa, used by smaller private vehicles, such as cars or forklifts, because they do not have as much space to place tanks. To increase autonomy, the H2 pressure is increased, but storage is also more expensive and the weight of the tank is increased.
Refueling is simple and similar to how to supply diesel or gasoline. The filling connector is provided with an infrared connection, which prevents overpressure and increases the safety of filling, since if the nozzle is incorrectly positioned the vehicle will not be recharged.
For the cars on the market, and with a pressure of H70, the pump will begin to fill the tank at a rate of about 100-120 grams per second, which will mean that the refueling of 5 kilograms is completed in approximately one minute. This speed will depend on the type of pump that the service station where we refuel has.
For heavy vehicles the nozzle is a little different but the refueling operation is also simple.
The connections for H70 or H35 are different, so there is no possibility of confusion, although in the case of H70, there are two very widespread models: the TK16 and the TK17, although it is the TK17 that is being imposed as a solution standard.
For H35, the TK25 has been standardized as a solution