1. Funded by FCH JU (Grant agreement No. 256823) 1 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 1

2. Funded by FCH JU (Grant agreement No. 256823) 2 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 2 Hydrogen can be produced by - water electrolysis using electricity - steam reforming of natural gas Delivery by - transportable containers - trailers - pipeline Electrolyser Electricity (e - ) Water (H 2 O) Hydrogen (H 2 ) Oxygen (O 2 ) Reformer Natural Gas (CH 4 ) Steam (H 2 O) Hydrogen (H 2 ) Carbon Dioxide (CO 2 )

3. Funded by FCH JU (Grant agreement No. 256823) 3 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 3 Electrolysers: - producing hydrogen and oxygen from water and (green) electricity - for immediate or later use - most often used in industrial applications - scalable size (0,1 to 20.000 m 3 /h) - can be easily regulated from 0 to 100 % - relatively short start up time (minutes) - produce very pure hydrogen at elevated pressures (1 to 30 bar)

4. Funded by FCH JU (Grant agreement No. 256823) 4 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 4 Reformers : - producing hydrogen from natural gas, steam and heat. - most often used in industrial applications - capacity ranges from a few hundred to more than 100 000 Nm 3 /h - operated 24/7 at constant load - relatively long start up time (days) - emit CO 2 - produced hydrogen is not very clean and at atmospheric pressure

5. Funded by FCH JU (Grant agreement No. 256823) 5 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 5 In an electrolyser cell, electricity causes dissociation of water into hydrogen and oxygen molecules. An electric current is passed between two electrodes separated by a conductive electrolyte or “ion transport medium”, producing hydrogen at the negative electrode (cathode) and oxygen at the positive electrode (anode). Two main technologies of electrolysers exist : electrolysers based on the - Alkaline electrolysis process and electrolysers based on the - PEM (Proton Exchange Membrane) electrolysis process. Their technical maturities, their operating temperatures and their electrolytes are different.

6. Funded by FCH JU (Grant agreement No. 256823) 6 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 6 Alkaline electrolysis : - most often used in industrial applications - electrolyte is a potassium hydroxide solution (KOH) - operating temperature ranges from 60 to 100°C - operating pressure ranges from 1 to 30 bar - relatively bulky systems - efficiency is around 65%. Figure 128: Electrolyser developed by Norsk Hydro

7. Funded by FCH JU (Grant agreement No. 256823) 7 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 7 PEM electrolysis : - key component is the membrane (polymer) – electrode (catalyst) system - anode: water is broken down in oxygen, electrons and protons - protons: migrate through the membrane - cathode: protons are reduced in hydrogen molecules - electrons: migrate via the external circuit to the cathode - membrane: good chemical stability, mechanical resistance, protons conductivity, gas separation - advantages of PEM electrolysers: load changes don’t have much influence on lifetime, high pressure - disadvantage: high costs of the electrolyte and electro catalysts - still at development stage Figure 129: PEM electrolyser

8. Funded by FCH JU (Grant agreement No. 256823) 8 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 8 Hazardous situations Prevention or mitigation measures Loss of segregation within system of H 2 and O 2 produced – process pressure is an aggravating factor as this increases amount of reactants in the system and burst pressure of equipment Process reliability and detection of O 2 in H 2 Formation of flammable mixture in container due to a H 2 leak Permanent ventilation and H 2 detection Fire due to failure/overheating of high current electrical components Electrical safety, fire detection In case of liquid electrolyte: short circuit from electrolyte leaks Quality of assembly, periodic inspection In case of liquid electrolyte: corrosive electrolyte leaksQuality of assembly, periodic inspection

9. Funded by FCH JU (Grant agreement No. 256823) 9 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 9 ISO 22734-1:2008 Hydrogen generators using water electrolysis process Part 1: Industrial and commercial applications, Edition 1 ISO 22734-2 Hydrogen generators using water electrolysis process Part 2: Residential applications, Edition 1

10. Funded by FCH JU (Grant agreement No. 256823) 10 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 10 - 2% of hydrogen is added in the natural gas - pre-heating to 350°C - desulphurization - process gas is mixed with steam - pre-heating to about 500°C - process gas flows through the reforming tubes filled with catalyst - Catalytic reactions produces syngas (H 2, CO, CO 2, H 2 O, CH 4 ). The reactions producing hydrogen are:CH 4 + H 2 O → CO + 3H 2 CO + H 2 O → CO 2 + H 2 - steam methane reforming reaction is very endothermic - syngas has a temperature of 850°C - then cooled down to about 350°C - flows through a CO converter - catalytic reaction produces H 2 and CO 2 from H 2 O and CO - cooling down to 35°C - condensation of remaining steam - raw hydrogen concentration is more than 70% with some impurities (mostly CO 2 ) - removal of impurities in a purification unit

11. Funded by FCH JU (Grant agreement No. 256823) 11 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 11 Figure 131: Steam methane reforming

12. Funded by FCH JU (Grant agreement No. 256823) 12 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 12 Units to be considered during safety assessment: burner, its flame and the combustion quality, the reforming tubes and steam production unit. explosive atmosphere might be ignited by the burner  increase of flame and gas temperature would damage materials of the reforming tubes.  incomplete combustion of gases leads to formation of deposits in the exchangers Main hazard for the reforming tubes is the formation of a leak on these tubes because of an early ageing of the reforming tubes. The main hazard for the steam production unit is an abnormal pressure increase.

13. Funded by FCH JU (Grant agreement No. 256823) 13 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 13 ISO 16110-1:2007 Hydrogen generators using fuel processing technologies Part 1: Safety, Edition 1 Applicable to stationary hydrogen generators intended for indoor and outdoor commercial, industrial, light industrial and residential use with a capacity of less than 400 m 3 /h. Aims to cover all significant hazards, hazardous situations and events relevant to hydrogen generators, with the exception of those associated with environmental compatibility (installation conditions), when they are used as intended and under the conditions foreseen by the manufacturer. A list of significant hazards and hazardous situations dealt with in this part of ISO 16110 is found in Annex A. This part of ISO 16110 is a product safety standard suitable for conformity assessment as stated in IEC Guide 104, ISO/IEC Guide 51 and ISO/IEC Guide 7.

14. Funded by FCH JU (Grant agreement No. 256823) 14 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 14 Hydrogen transport to / from refineries. Compressed hydrogen transport in metallic pipelines. Above-ground piping systems or underground piping systems (open trench and/or cathodic protection). Material:stainless steel Figure 132: Hydrogen pipeline network of Air Liquide in Northern Europe

15. Funded by FCH JU (Grant agreement No. 256823) 15 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 15 HazardSafety measures Rupture of pipes and fittings because of hydrogen embrittlement Hydrogen compatible materials should be chosen. Corrosion for underground piping Piping must be externally coated to an approved specification, to protect against soil corrosion by cathodic protection. Rupture of the pipe material due to lightning strikes or ground fault conditions Electrical continuity between underground hydrogen piping and above ground piping, or other metal structures, should be adhered. All above-ground pipelines shall have electrical continuity across all connections, except insulating flanges, and shall be earthed at suitable intervals to protect against the effects of lightning and static electricity Rupture due to external forces Piping should not be exposed to external forces which can cause a failure or dangerous situation. The main cause of pipe rupture is attack by external operation (e.g. when a mechanical digger knocks on a pipe). Hazards specific to underground piping It is preferable to have no flanged or other mechanical joints underground. Only gaseous hydrogen pipes with welded joints may be buried. Table 41: Safety measures for pipes

16. Funded by FCH JU (Grant agreement No. 256823) 16 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 16 Consumptions of up to a 200 Nm 3 /h: CGH 2 in transportable containers or trailers Larger consumptions: hydrogen production at the site of use Figure 133: Examples of compressed hydrogen tube trailers

17. Funded by FCH JU (Grant agreement No. 256823) 17 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 17 In order to increase its density, hydrogen may be liquefied and transported by liquid hydrogen tankers. However, storing liquid hydrogen over a long period of time is challenging because of its rapid evaporation in case of parasitic heat input. Tankers are insulated, and they may have large capacities exceeding 60 000L. Figure 134: Liquid hydrogen tanker

18. Funded by FCH JU (Grant agreement No. 256823) 18 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 18 Safety devices of trailers or tankers:  Safety relief valves and burst discs protect the vessels from an excessive pressure  Safety relief valves start to open at their set pressure. They re-set when the pressure is at 90% of the set pressure.  burst discs are metal foil discs which are designed to rupture at a set pressure. They do not re-set once they have burst.  Emergency valves prevent any loss of hydrogen in case of pipes failures, or in case of an accident during the trailer / tanker filling or discharge.  Vacuum safety devices protect the outer jacket from bursting and / or the inner vessel from collapsing in the case of a product leak into the vacuum interspace  Anti tow-away devices to prevent the vehicle from moving when the cabin’s doors are open OR when a product transfer and / or vent hose is connected to the road transport equipment pipework coupling.

19. Funded by FCH JU (Grant agreement No. 256823) 19 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 19 IGC Doc 81/06/E: Road Vehicle Emergency and Recovery, Revision of Doc 81/01, European Industrial Gases Association AISBL ISO 10961 specifies the requirements for the design, construction, testing and initial inspection of a transportable cylinder bundle. Trailers EN 13807 This European Standard specifies the requirements for the design, manufacture, identification and testing of a battery vehicle. ADR: Accord European Relatif au Transport International du Merchandis Dangereuses par Route European Agreement concerning the International Carriage of Dangerous Goods by Road

20. Funded by FCH JU (Grant agreement No. 256823) 20 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 20 Hydrogen installations usually (i) store hydrogen delivered by road (ii) distribute hydrogen to point of use The storage function is typically performed in one of the following two ways: 1.Even exchange of containers : delivery and storage in transportable hydrogen containers To ensure continuity of supply, two hydrogen containers are connected (Fig. 135) 2. Product transfer : Hydrogen is transferred by pressure difference from the delivery trailer to a stationary hydrogen storage tank (Fig. 136).

21. Funded by FCH JU (Grant agreement No. 256823) 21 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 21 Figure 135: Block diagram for hydrogen supply from two hydrogen trailers

22. Funded by FCH JU (Grant agreement No. 256823) 22 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 22 Figure 136: Flow diagram for gas transfer

23. Funded by FCH JU (Grant agreement No. 256823) 23 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 23 Main risk: tearing the high pressure flexible hoses by moving a container still connected to the fixed installation. Preventive measures:  Prevention of movement of trailers that are connected to the installation, e.g. by locking the trailer’s brakes when the high pressure hose is connected to the trailer.  Isolation valve on the trailer located on the forward side. In case of high pressure hose rupture, the trailer can be safely isolated in order to prevent it from being emptied

24. Funded by FCH JU (Grant agreement No. 256823) 24 © HyFacts Project 2012/13 CONFIDENTIAL – NOT FOR PUBLIC USE 24 H 2 supply system Installation: ISO/DIS 20100 clause 5.2 Gaseous hydrogen supply by tube trailers and Multi Cylinder Packs (MCPs) and 14 Separation distances List of all the standards of TC 58 and TC 197 relative to vessels/tanks ISO 15399 : Gaseous hydrogen. Cylinders and tubes for stationary storage