ENERGY

GREEN HYDROGEN

Hydrogen is our absolute number one. So naturally we also have a favourite colour for our element! H2 technology unleashes its full power when green hydrogen is used. What exactly do we mean by ‘green’ hydrogen? That is a matter of definition. As the companies involved in the CEP see it, the green hydrogen used should at least meet the criteria defined for the European CertifHy process.

According to this definition, hydrogen that is produced on the basis of renewable energies and complies with defined greenhouse gas reduction values is considered green hydrogen. H2 production can be through renewable electricity in an electrolysis plant, or through steam reforming of biomethane, i.e. on the basis of renewable biomass. For both processes, the greenhouse gas emissions associated with production must not exceed 36.4 gCO2eq/MJ. This corresponds to a 60% reduction compared to hydrogen production based on fossil natural gas. The best option, because it is completely free of greenhouse gas emissions, is electrolysis based on wind and/or photovoltaic electricity. This, we like!

LOGISTICS

As the most common element in the universe, hydrogen is available in virtually infinite quantities. That’s good? Yes, but there is a catch: hydrogen occurs almost exclusively in chemically bound form. Therefore, energy is needed for its production in the first step. In the interest of CO2-neutral and demand-driven production, the CEP partners favour electrolysis from renewable sources. The hydrogen can be produced directly and autonomously at the filling station or centrally in larger plants.

For economically viable H2 production, a supraregional supply of hydrogen will be unavoidable. Distribution can take place via tankers or pipelines. Smaller quantities of compressed hydrogen at up to 500 bar or liquid hydrogen (LH2) at -253° C can be transported by tanker. Approximately 3,500 kg of hydrogen can be transported in an LH2 trailer. For larger quantities, pipelines for gaseous hydrogen are recommended as a logistics solution. We will evaluate the various distribution options based on the relevant studies and our own data. The goal is to create a catalogue of criteria that guarantees a goal-oriented weighing of the options.

STORAGE

Fun fact: hydrogen is the lightest element in the universe – 14 times lighter than air. So what? In purely factual terms, at filling stations its low density allows for both gaseous storage under high pressure, and storage as cryogenic, liquefied hydrogen at -253°C. Our work has shown that gaseous storage is more advantageous for cars (700 bar/ 10 kg) as well as buses (350 bar/ 35 kg). The best thing: neither during transport and storage nor in the vehicle tanks does significant diffusion occur. So our number one is also a sure thing.