How can hydrogen be generated, where can it be utilized, and what distribution options are available? These issues were addressed in the research “Hydrogen Technology Screening” conducted on behalf of N-Ergie Aktiengesellschaft by Friedrich-Alexander University Erlangen-Nürnberg (FAU).
During the energy transition, green hydrogen produced from renewable sources will become an important energy carrier. This is a key result of a study conducted by a research group from FAU’s Chair of Energy Process Engineering in Erlangen.
This is especially true in areas where there are few other options for achieving carbon neutrality. These include industrial operations and substantial portions of the heating industry, as opposed to the mobility sector, which may be largely electrified. Long-term usage of gas network infrastructure and growing replacement of today’s natural gas with climate-neutral energy sources such as hydrogen is a good approach to get to climate neutrality.
The study, directed by Prof. Dr. Jürgen Karl, arose from the reality that regional and supra-regional distribution structures are required for the breakthrough of hydrogen technology. Hydrogen will only be accessible to a limited level in the near and medium term due to the large capabilities required for the generation of renewable energy. Furthermore, much of this is imported rather than manufactured in Germany. Gaseous distribution via pipes is proving to be the most efficient – at least over large distances.
On the one hand, regionally produced hydrogen may be utilized by industrial clients in the region who, at the moment, must wait a long time for a connection to a pure hydrogen network. On the other side, it is possible to use it to generate district heating.
Three manufacturing techniques emerge as a consequence of the scientific investigation: The first step is to split water using an electrolyser. This method is widely recognized as a crucial technique for producing green hydrogen, and it may be used in close proximity to potential consumers, for example.
The generation of hydrogen from methane pyrolysis of biomethane is the second alternative. Using power generated from renewable sources, methane from biogas is thermally divided into hydrogen and solid carbon. Unlike incineration, this technique does not emit CO 2 into the atmosphere, which is harmful to the environment. Even CO 2 is removed from the atmosphere by this method. The pyrolysis-derived hydrogen, when combined together with the thermal power station’s CO 2 neutral district heating, might help Nuremberg achieve even more CO 2 neutral district heating.
The thermochemical conversion of biogenic wastes is a third method of producing hydrogen that has received less attention in the public debate thus far. Heat is used to gasify leftover forest wood or sewage sludge, for example. The hydrogen is isolated from the synthesis gas generated during the following treatment.
Within this process, the electrically heated steam gasification of biomass, which has received little investigation, looks to be particularly interesting, since it offers a very high degree of efficiency as the technology matures. Only approximately a third of the energy required to generate hydrogen comes from electricity, while the other two-thirds comes from biomass.