The ideal hydrogen storage:
light, affordable, safe

An optimal hydrogen storage has little efficiency loss, requires minimal safety precautions, and can store large amounts of H2 in a small space. For mobile storage solutions, transport should be simple and inexpensive. The weight of the storage unit plays a particularly important role. Although pressure and liquid storage of hydrogen are already commercially established solutions today, the existing physical and chemical storage technologies are far from ideal for hydrogen storage.

Hydrogen has a very high permeability and can diffuse through porous materials or even metals. Therefore, storage requires special materials to minimize diffusion losses.

Goal: minimal energy losses during conversion and storage

Efficient hydrogen storage seeks to minimize the loss of hydrogen and energy during the storage process as much as possible. To keep the energy required for compression to a minimum, the pressure with which the hydrogen emerges from electrolysis (30–60 bar) is utilized. When hydrogen undergoes a chemical transformation for storage purposes, the two-step conversion process (hydrogen => chemical storage medium => hydrogen) should consume as little energy as possible.

Advantages and disadvantages of different
hydrogen storage technologies

Physical pressure storage


  • Inexpensive
  • Already in commercial use
  • Compensates for the low volumetric energy density of H2


  • Compression consumes energy (5–12% of the H2 energy content)
  • The higher the pressure, the larger the storage vessel/the wall thickness
  • High transport costs due to weight

Physical storage of liquid hydrogen


  • Significantly higher volumetric energy content compared to physical storage
  • Easier transport


  • High energy loss in the storage process (30–40%)
  • Highly insulating special steel tanks necessary
  • Cooling units required

Today’s physical H2 storage has central disadvantages: high efficiency losses due to compression or cooling and high requirements for material stability and safety precautions.

Chemical H2 storage


  • Easy handling
  • Lower safety requirements
  • Good transportability


  • High energy efficiency losses in the storage process

In chemical storage, hydrogen is combined with other elements. These can be hydrides (metal alloys), nitrogen compounds such as ammonia, aminoborane, or hydrazine, or hydrogen carriers that absorb hydrogen through a chemical reaction with the help of catalysts and release it through another chemical reaction.

Typical application scenarios
for hydrogen storage

Markets with the greatest potential for decarbonization through green hydrogen


  • Reactant: Steel from direct reduction
  • Material use: Ammonia, chemicals

Energy sector

  • As long-term storage for renewable energies


  • Long-distance truck traffic
  • Long-distance air traffic
  • Long-distance maritime traffic


  • District heating for residential and office buildings

Which type of hydrogen storage
for which application?

Stationary Applications

Pressure gas storage with PED approval, which are placed and filled directly at the place of consumption.


Refilling of the TPED-approved fuel storage systems for ships at the HydroExceed hydrogen hub in Rostock-Laage, as well as their transportation to the customer.

Mobile Applications

TPED-approved hydrogen storage systems for operating vehicles, particularly in the maritime sector. The filling and emptying processes occur directly at the site of operation.