Hydrogen dispensing process and system

1. A process for dispensing gaseous hydrogen, comprising the steps of:

a) providing a first vessel comprising a first quantity of gaseous hydrogen at a pressure in the range of from 350 to 1000 bar absolute and a temperature in the range of from −20° C. to 50° C.;

b) passing in the range of from 40 to 100 wt %, based on the weight of the first quantity, of the first quantity of gaseous hydrogen from the first vessel through an isenthalpic valve to obtain a cold second quantity of gaseous hydrogen having a temperature in the range of from −100 to −20° C.;

c) dispensing the cold second quantity of gaseous hydrogen to a second storage vessel; and

d) providing further gaseous hydrogen to the first vessel to replace the hydrogen which was dispensed in step (c);

wherein the first vessel has a hydrogen capacity in the range of from 3 to 15 kg of hydrogen and during step (b) no further hydrogen is provided to the first vessel.

2. A process according to claim 1 , wherein step (d) further comprises cooling the further gaseous hydrogen to a temperature in the range as defined in step (a) of claim 1 .

3. A process according to claim 1 , wherein the second storage vessel is a hydrogen fuel tank of a vehicle.

4. A process according to claim 1 , wherein the further gaseous hydrogen is provided from a gaseous hydrogen storage vessel or from a pipeline.

5. A system for dispensing gaseous hydrogen, comprising:

a gaseous hydrogen storage vessel or a gaseous hydrogen pipeline comprising an outlet for gaseous hydrogen;

a first vessel, suitable to contain at least pressurised gaseous hydrogen in the range of from 3 to 15 kg at a pressure above 250 bar absolute having an inlet and an outlet for gaseous hydrogen;

means for providing gaseous hydrogen from the outlet of the hydrogen storage vessel or hydrogen pipeline to the inlet of the first vessel;

a valve suitable for controlling a flow of gaseous hydrogen which is or is part of the inlet for gaseous hydrogen of the first vessel or is located in the means for providing gaseous hydrogen to the first vessel;

a gaseous hydrogen dispenser having an inlet and an outlet for gaseous hydrogen;

an isenthalpic valve suitable for controlling a flow of gaseous hydrogen; and

means for providing gaseous hydrogen from the outlet of the first vessel to the inlet of the gaseous hydrogen dispenser;

wherein the isenthalpic valve is or is a part of the outlet for gaseous hydrogen of the first vessel or is located in the means for providing gaseous hydrogen from the first vessel to the gaseous hydrogen dispenser; and

wherein the means for providing gaseous hydrogen from the first vessel to the gaseous hydrogen dispenser is at least partly insulated.

6. A system according to claim 5 , wherein the first vessel is located subsurface and comprises a wall having a high thermal conductivity which is in heat exchange contact with a heat exchange medium.

7. A system according to claim 6 , wherein the wall having a high thermal conductivity is a metal wall.

8. A system according to claim 7 wherein the metal is selected from the group consisting of aluminium, steel, stainless steel or a combination thereof.

9. A system according to claim 6 , wherein the heat exchange medium is the soil.