With a share of 75 %, hydrogen is the most frequent element in our solar system. Green hydrogen and its derivatives are considered a key technology for a successful energy transition and the reduction of carbon dioxide emissions. The National Strategy on Hydrogen adopted on June 10, 2020 is one of the political measures aimed at getting the market up and running.
Hydrogen color theory - different types of production
Depending on the type of production, different colors are assigned to hydrogen - gray, blue, turquoise, and green. In this comparison, gray hydrogen is the most economical but at the same time the most polluting type due to the process of steam reforming of natural gas. The production of blue hydrogen is comparable to that of gray hydrogen. The difference lies in the separation and storage of up to 90 % of the CO2 generated. Turquoise hydrogen is produced by methane pyrolysis from the thermal splitting of methane (CH4), a process still in development though. Green hydrogen is expected to play an important role in future. Sustainable electricity (e.g. from solar power or wind power) is used in electrolyzers to generate hydrogen from water. In this procedure water (H2O) is split into two components: hydrogen and oxygen.
Fields of application of hydrogen
Nowadays, hydrogen is primarily used in the chemical and petrochemical industry as well as in the steel industry. This includes the production of ammonia for fertilizers and the use in refineries for oil processing. Green hydrogen can therefore help to reduce CO2 emissions in many industries, thus valuably contributing to the transformation of a wide range of industrial sectors and production processes by replacing fossil raw materials.
The possibilities of green hydrogen are not just limited to industrial applications. Green hydrogen also offers potential in the energy industry and for mobility. In comparison to battery electric vehicles (BEV), vehicles with hydrogen-based drive technology (fuel cell or H2 combustion engines) stand out in terms of refueling speed as well as range. In addition, hydrogen-based drive technologies also create new opportunities for a climate-neutral mobility development in the heavy-duty and transportation sectors, on rails, in seafaring, and in aviation. Furthermore, green hydrogen can be used in this regard to produce synthetic fuels to power conventional combustion engines.
Fuel cells can convert stored hydrogen into electricity and provide the latter on demand. This is always the case when the amount of electricity generated from wind and solar power is too low compared to the electricity demand. The heat which is generated by operating fuel cells can thereby be used for heating purposes in cogeneration (CHP).
Today gas pipelines are already being rededicated to the establishment of a supply structure with hydrogen. It is possible to distribute hydrogen directly to consumers by conversion of transregional transport pipelines as well as urban gas pipelines. The advantage is obvious: the costs of new infrastructural investments are lower and there’s less intrusion into nature with new pipeline routes.
Expansion of production capacities in Germany
In Germany, green hydrogen is considered one of the key elements to reducing CO2 emissions. Green hydrogen accounts for approximately 5 % of the total annual hydrogen production of about 55 TWh to 60 TWh. The essential part of the hydrogen can be classified as grey according to the production method.
Studies on future demands of hydrogen generated by electrolysis classify these into high and low scenarios. In its hydrogen roadmap, the Fraunhofer Institute forecasts a spectrum of demand ranging from 4 TWh for 2030 (low scenario) to 20 TWh (high scenario). For 2050, the demand is estimated at 250 TWh in the low scenario and 800 TWh in the high scenario. To obtain this amount of hydrogen, both importations and domestic production will be necessary. The required energy for domestic production shall primarily be obtained from wind and photovoltaic power plants. To achieve this purpose, significant efforts are inevitable. Capacities to produce green hydrogen are yet limited, as the green power sources and the electrolysis capacity must be built up.
Global potentials of green hydrogen production
On a global scale, significant potentials for sustainable hydrogen production are located on the African continent. According to forecasts by the German Federal Ministry of Education and Research in its Potential Atlas of Hydrogen, the annual production volumes of green hydrogen could reach up to 165.000 TWh for the West African region alone. Favorable environmental conditions such as solar and wind availability enable prime costs which are stated at 2,50 € / kg H2 at generated levels of 120.000 TWh (estimation for Germany in 2050: 3,80 € / kg H2). Key influencing factor are the by 30 % lower levelized costs of electricity compared to Germany. Therefore, valuable synergies between Africa, Europe, and Germany could be developed in the future.
The high ambitions on hydrogen are also underlined by a study aimed at researching international strategies on hydrogen, commissioned by the World Energy Council – Germany. The study offers insights into the increasing amount of strategies on hydrogen as an indication for dynamic market growth. Among the world’s strongest national economies, 20 states already have adopted a national strategy on hydrogen or are in the conclusion stage.
Examples of projects in Germany
There are currently several projects linked to green hydrogen either in planning or under construction. An example is the largest electrolysis plant in Bavaria which is under construction in the district of Wunsiedel. The plant with an electrolysis capacity of 8,75 MW is a cooperation project between Siemens AG, gas distributor of Wundsiedel Rießner Gase and the public utility company of Wunsiedel (Wunsiedler Stadtwerke SWW). Commissioning is planned for summer of 2022. The designed production capacity thereby aims for an annual output of 1.350 tons of hydrogen. The generated hydrogen will be distributed by a trailer to regions in northern Bavaria, Thuringia and the border region of the Czech Republic.
A funded innovative energy park is currently under construction near the town of Goethestadt Bad Lauchstädt (Saalekreis) in Saxony-Anhalt in the framework of the so called “Living labs”. The innovative nature of this project is an absolute novelty. For the first time, the connectivity between a wind farm (nominal output 50 MW) and a large-scale electrolysis plant (nominal output 30 MW) will be tested along with the conversion of a gas pipeline for hydrogen transport and with the commercialization of the hydrogen. The next phase will be the storage of the hydrogen in a salt cavern. The completion and commissioning are planned to take place in 2024. You can find more information on the energy park of Bad Lauchstädt here.
The authors work with greenValue GmbH. greenValue is a service provider in the sector of renewable energies with long-standing expertise and shows various references for successfully managed projects. Among other professions, greenValue provides services like project management and technical assistance during M&A processes. The main energy fields are at this time hydrogen, liquefied natural gas, and biomethane plants.
July 1, 2022, greenvalue.de