Hydrogen infrastructure. A hydrogen infrastructure is the infrastructure of hydrogen pipeline transport, points of hydrogen production and hydrogen stations for distribution as well as the sale of hydrogen fuel, and thus a crucial prerequisite before a successful commercialization of fuel cell technology.

The hydrogen infrastructure would consist mainly of industrial hydrogen pipeline transport and hydrogen-equipped filling stations. Hydrogen stations which were not situated near a hydrogen pipeline would get supply via hydrogen tanks, compressed hydrogen tube trailers, liquid hydrogen trailers, liquid hydrogen tank trucks or dedicated onsite production.

Pipelines are the cheapest way to move hydrogen over long distances compared to other options. Hydrogen gas piping is routine in large oil-refineries, because hydrogen is used to hydrocrack fuels from crude oil. The IEA recommends existing industrial ports be used for production and existing natural gas pipelines for transport: also international co-operation and shipping.

South Korea and Japan, which as of 2019 lack international electrical interconnectors, are investing in the hydrogen economy. In March 2020, the Fukushima Hydrogen Energy Research Field was opened in Japan,  claiming to be the world's largest hydrogen production facility. Much of the site is occupied by a solar array; power from the grid is also used for electrolysis of water to produce hydrogen fuel.

Network

Hydrogen highways
A hydrogen highway is a chain of hydrogen-equipped filling stations and other infrastructure along a road or highway which allow hydrogen vehicles to travel.

Hydrogen stations
Hydrogen stations which are not situated near a hydrogen pipeline get supply via hydrogen tanks, compressed hydrogen tube trailers, liquid hydrogen trailers, liquid hydrogen tank trucks or dedicated onsite production. Some firms as ITM Power are also providing solutions to make your own hydrogen (for use in the car) at home. Government supported activities to expand an hydrogen fuel infrastructure are ongoing in the US state of California, in some member states of the European Union (most notably in Germany) and in particular in Japan.

Hydrogen pipeline transport
Hydrogen pipeline transport is a transportation of hydrogen through a pipe as part of the hydrogen infrastructure. Hydrogen pipeline transport is used to connect the point of hydrogen production or delivery of hydrogen with the point of demand, pipeline transport costs are similar to CNG, the technology is proven, however most hydrogen is produced on the place of demand with every  an industrial production facility. , there are  of low pressure hydrogen pipelines in the US and  in Europe.

According to a 2024 research report, the United States has 1,600 miles (2,570 kilometers) of hydrogen pipelines; the global total stands at 2,800 miles (4,500 kilometers). The World Economic Forum, in December 2023, estimated that Europe had approximately 1,600 kilometers of hydrogen pipelines.

Hydrogen embrittlement (a reduction in the ductility of a metal due to absorbed hydrogen) is not a problem for hydrogen gas pipelines. Hydrogen embrittlement only happens with 'diffusible' hydrogen, i.e. atoms or ions. Hydrogen gas, however, is molecular (H2), and there is a very significant energy barrier to splitting it into atoms.

Buffer for renewable energy
The National Renewable Energy Laboratory believes that US counties have the potential to produce more renewable hydrogen for fuel cell vehicles than the gasoline they consumed in 2002.

As an energy buffer, hydrogen produced via water electrolysis and in combination with underground hydrogen storage or other large-scale storage technologies, could play an important role for the introduction of fluctuating renewable energy sources like wind or solar power.

Hydrogen production plants
98% of hydrogen production uses the steam reforming method. Methods such as electrolysis of water are also used. The world's largest facility for producing electrolytic hydrogen fuel is claimed to be the Fukushima Hydrogen Energy Research Field (FH2R), a 10MW-class hydrogen production unit, inaugurated on 7 March 2020, in Namie, Fukushima Prefecture. The site occupies 180,000 square meters of land, much of which is occupied by a solar array; but power from the grid is also used to conduct electrolysis of water to produce hydrogen fuel.

Hydrogen pipeline transport 

Hydrogen pipeline transport is a transportation of hydrogen through a pipe as part of the hydrogen infrastructure.

History
1938 – Rhine-Ruhr The first  hydrogen pipes that are constructed of regular pipe steel, compressed hydrogen pressure , diameter . Still in operation.
1973 –  pipeline in Isbergues, France.
1985 – Extension of the pipeline from Isbergues to Zeebrugge
1997 – Connection of the pipeline to Rotterdam
1997 – 2000: Development of two hydrogen networks, one near Corpus Christi, Texas, and one between Freeport and Texas City.
2009 –  extension of the pipeline from Plaquemine to Chalmette.

Economics

Hydrogen pipeline transport is used to transport hydrogen from the point of production or delivery to the point of demand. Although hydrogen pipeline transport is technologically mature, and the transport costs are similar to those of CNG, most hydrogen is produced in the place of demand, with an industrial production facility every

Piping
For process metal piping at pressures up to , high-purity stainless steel piping with a maximum hardness of 80 HRB is preferred. This is because higher hardnesses are associated with lower fracture toughness so stronger, higher hardness steel is less safe.

Composite pipes are assessed like:
carbon fiber structure with fiberglass overlay  .
perfluoroalkoxy (PFA, MFA).
polytetrafluoroethylene (PTFE)
fluorinated ethylene propylene (FEP) .
carbon-fiber-reinforced polymers (FRP)

Fiber-Reinforced Polymer pipelines (or FRP pipeline) and reinforced thermoplastic pipes are researched.

Carrying hydrogen in steel pipelines (grades: API5L-X42 and X52; up to 1,000psi/7,000kPa, constant pressure/low pressure cycling) does not lead to hydrogen embrittlement. Hydrogen is typically stored in steel cylinders without problems.
Coal gas (also known as town gas) is 50% hydrogen and was carried in cast-iron pipes for half a century without any embrittlement issues.

Infrastructure

2024: USA –  of low pressure hydrogen pipelines
2024: Europe –  of low pressure hydrogen pipelines.

Hydrogen highway 
A hydrogen highway is a chain of hydrogen-equipped public filling stations, along a road or highway, that allows hydrogen powered cars to travel. William Clay Ford Jr. has stated that infrastructure is one of three factors (also including costs and manufacturability in high volumes) that hold back the marketability of fuel cell cars.

Supply issues, cost and pollution
Hydrogen fueling stations generally receive deliveries of hydrogen by tanker truck from hydrogen suppliers. An interruption at a hydrogen supply facility can shut down multiple hydrogen fueling stations. A hydrogen fueling station costs between $1 million and $4 million to build.

As of 2019, 98% of hydrogen is produced by steam methane reforming, which emits carbon dioxide. The bulk of hydrogen is also transported in trucks, so pollution is emitted in its transportation.

Hydrogen station

A hydrogen station is a storage or filling station for hydrogen fuel. The hydrogen is dispensed by weight. There are two filling pressures in common use: H70 or 700 bar, and the older standard H35 or 350 bar. , around 550 filling stations were available worldwide. According to H2stations.org by Ludwig-Bölkow-Systemtechnik (LBST), as of the end of 2023, there were 921 hydrogen refueling stations globally, although this number clearly conflicts with those published by AFDC. The distribution of these stations is highly uneven, with a concentration in East Asia, particularly in China, Japan and South Korea; Central Europe and California in the United States. Other regions have very few, if any, hydrogen refuelling stations.

Delivery methods 
Hydrogen fueling stations can be divided into off-site stations, where hydrogen is delivered by truck or pipeline, and on-site stations that produce and compress hydrogen for the vehicles.

Types of recharging stations

Home hydrogen fueling station 
Home hydrogen fueling stations are available to consumers. A model that can produce 12 kilograms of hydrogen per day sells for $325,000.

Solar powered water electrolysing hydrogen home stations are composed of solar cells, power converter, water purifier, electrolyzer, piping, hydrogen purifier, oxygen purifier, compressor, pressure vessels and a hydrogen outlet.

Disadvantages

Volatility
Hydrogen fuel is hazardous because of its low ignition energy, high combustion energy, and because it easily leaks from tanks. Explosions at hydrogen filling stations have been reported.

Supply
Hydrogen fuelling stations generally receive deliveries by truck from hydrogen suppliers. An interruption at a hydrogen supply facility can shut down multiple hydrogen fuelling stations due to an interruption of the supply of hydrogen.

Costs

There are far fewer Hydrogen filling stations than gasoline fuel stations, which in the US alone numbered 168,000 in 2004. Replacing the US gasoline infrastructure with hydrogen fuel infrastructure is estimated to cost a half trillion U.S. dollars. A hydrogen fueling station costs between $1 million and $4 million to build. In comparison, battery electric vehicles can charge at home or at public chargers. As of 2023, there are more than 60,000 public charging stations in the United States, with more than 160,000 outlets. A public Level 2 charger, which comprise the majority of public chargers in the US, costs about $2,000, and DC fast chargers, of which there are more than 30,000 in the U.S., generally cost between $100,000 and $250,000, although Tesla superchargers are estimated to cost approximately $43,000.

Freezing of the nozzle
During refueling, the flow of cold hydrogen can cause frost to form on the dispenser nozzle, sometimes leading to the nozzle becoming frozen to the vehicle being refueled.

Locations 
Consulting firm Ludwig-Bölkow-Systemtechnik tracks global hydrogen filling stations and publishes a map.

Asia
In 2019, there were 178 publicly available hydrogen fuel stations in operation.

, there are 167 publicly available hydrogen fuel stations in operation in Japan. In 2012 there were 17 hydrogen stations, and in 2021, there were 137 publicly available hydrogen fuel stations in Japan.

By the end of 2023, China had built 354 hydrogen refueling stations.

In 2019, there were 33 publicly available hydrogen fuel stations in operation in South Korea. In November 2023, however, due to hydrogen supply problems and broken stations, most fueling stations in South Korea offered no hydrogen. 41 out of the 159 hydrogen stations in the country were listed as open, and some of these were rationing supplies of hydrogen.

Europe
In 2019, there were 177 stations in Europe. According to H2stations.org by Ludwig-Bölkow-Systemtechnik (LBST), there were 265 hydrogen refuelling stations in Europe by the end of 2023.

 there were 105 hydrogen fuel stations in Germany,  there were 5 publicly available hydrogen fuel stations in France, 3 publicly available hydrogen fuel stations in Iceland, one publicly available hydrogen fuel station in Italy, 4 publicly available hydrogen fuel stations in The Netherlands, 2 publicly available hydrogen fuel stations in Belgium, 4 publicly available hydrogen fuel stations in Sweden, 3 publicly available hydrogen fuel stations in Switzerland and 6 publicly available hydrogen fuel stations in Denmark. Everfuel, the only operator of hydrogen stations in Denmark, announced in 2023 the closure of all of its public hydrogen stations in the country.

 there were 2 publicly available hydrogen fuel stations in Norway, both in the Oslo area. Since the explosion at the hydrogen filling station in Sandvika in June 2019, the sale of hydrogen cars in Norway has halted. In 2023, Everfuel announced the closure of its two public hydrogen stations in Norway and cancelled the opening of a third. In 2024 Shell discontinued its hydrogen fuel projects in Norway.

 there were 11 publicly available hydrogen fuel stations in the United Kingdom, but as of 2023, the number decreased to 5. In 2022, Shell closed its three hydrogen stations in the UK,

North America

Canada
As of July 2023, there were 10 fueling stations in Canada, 9 of which were open to the public:
 British Columbia: Five stations are in the Greater Vancouver Area and Vancouver Island, with one station in Kelowna. All six stations are operated by HTEC (co-branded with Shell and Esso).
 Ontario: One station in Mississauga is operated by Hydrogenics Corporation. The station is only available to certain commercial customers.
 Quebec: Three stations in the Greater Montreal area are operated by Shell, and one station in Quebec City is operated by Harnois Énergies (co-branded with Esso).

United States
, there were 54 publicly accessible hydrogen refueling stations in the US, 53 of which were located in California, with one in Hawaii.

California:  there were 53 retail stations. Continued state funding for hydrogen refueling stations is uncertain. In September 2023, Shell announced that it had closed its hydrogen stations in the state and discontinued plans to build further stations. In 2024 it was reported that "a majority of the hydrogen stations in Southern California are offline or operating with reduced hours" due to hydrogen shortages and unreliable station performance.
Hawaii opened its first hydrogen station at Hickam in 2009. In 2012, the Aloha Motor Company opened a hydrogen station in Honolulu.  however, only one publicly accessible station was in operation in Hawaii.
Michigan: In 2000, the Ford Motor Company and Air Products & Chemicals opened the first hydrogen station in North America in Dearborn, MI.   no publicly accessible stations were in operation in Michigan.

Oceania
In 2021, the first Australian publicly available hydrogen fuel station opened in Canberra, operated by ActewAGL.

Hydrogen tank

A hydrogen tank (other names- cartridge or canister) is used for hydrogen storage. The first type IV hydrogen tanks for compressed hydrogen at  were demonstrated in 2001, the first fuel cell vehicles on the road with type IV tanks are the Toyota FCHV, Mercedes-Benz F-Cell and the GM HydroGen4.

Low-pressure tanks
Various applications have allowed the development of different H2 storage scenarios.
Recently, the Hy-Can consortium has introduced a small one liter,  format.  Horizon Fuel Cells is now selling a refillable  metal hydride form factor for consumer use called HydroStik.

Type I
 Metal tank (steel/aluminum)
 Approximate maximum pressures: aluminum , steel .

Type II
 Aluminum tank with filament windings such as glass fiber/aramid or carbon fiber around the metal cylinder. See composite overwrapped pressure vessel.
 Approximate maximum pressures: aluminum/glass , steel/carbon or aramide .

Type III
 Tanks made from composite material, fiberglass/aramid or carbon fiber with a metal liner (aluminum or steel). 
 Approximate maximum pressures: aluminum/glass , aluminum/aramid , aluminium/carbon .

Type IV

 Composite tanks such of carbon fiber with a polymer liner (thermoplastic). See rotational molding and fibre-reinforced plastic.
 Approximate maximum pressure: .

Type V
 All-composite, linerless tank. Composites Technology Development (Colorado, USA) built a prototype tank for a satellite application in 2010 although it had an operating pressure of only 200 psi and was used to store argon.
 Approximate maximum pressure: .

Tank testing and safety considerations

In accordance with ISO/TS 15869 (revised):
 Burst test: the pressure at which the tank bursts, typically more than 2× the working pressure.
 Proof pressure: the pressure at which the test will be executed, typically above the working pressure.
 Leak test or permeation test, in NmL/hr/L (Normal liter of H2/time in hr/volume of the tank.)
 Fatigue test, typically several thousand cycles of charging/emptying.
 Bonfire test where the tank is exposed to an open fire.
 Bullet test where live ammunition is fired at the tank.

This specification was replaced by ISO 13985:2006 and only applies to liquid hydrogen tanks.

Actual Standard EC 79/2009
 U.S. Department of Energy maintains a hydrogen safety best practices site with a lot of information about tanks and piping.  They dryly observe "Hydrogen is a very small molecule with low viscosity, and therefore prone to leakage.".

Metal hydride storage tank

Magnesium hydride
Using magnesium for hydrogen storage, a safe but weighty reversible storage technology. Typically the pressure requirement are limited to .
The charging process generates heat whereas the discharge process will require some heat to release the H2 contained in the storage material. To activate these types of hydrides, at the current state of development you need to reach approximately .

Other hydrides

See also sodium aluminium hydride

Research
 2008 - Japan, a clay-based film sandwiched between prepregs of CFRP.

See also
 Hydrogen leak testing
 Hydrogen sensor
 Gas cylinder
 Hydrogen compressor
 Liquid hydrogen

References

Sources

External links
Hydrogen Embrittlement group
 California Hydrogen Highway
 Hydrogen Highway, Norway to Germany
 Interactive map of hydrogen stations in Europe and worldwide
 Interactive map of hydrogen stations in Europe and worldwide (includes non-public stations)
 H2Map.com Map of hydrogen refueling stations in the UK
 H2stations.org Map of hydrogen refueling stations worldwide (GIS)
 California Fuel Cell Partnership Map Map of hydrogen fueling stations in California, with real-time status reports
 EUhyfis
 ISO-TC 197

 
Industrial gases
Hydrogen storage
Pressure vessels
Pipeline transport
Piping
Hydrogen technologies
Road infrastructure
Hydrogen economy
Filling stations
Sustainable transport
Gas technologies