Discussion paper
Green hydrogen - A contribution to the security of supply and decarbonisation of Switzerland
An overview of the most important questions and recommendations for decision-makers from politics, administration, research and business.
Author and project management: Christian Holzner (SATW)
Advisory experts SATW Energy Group: Marco Berg (Stiftung Klimaschutz und CO₂-Kompensation KliK), Konstantinos Boulouchos (ETH Zurich), Bernhard Braunecker (Schweizerische Physikalische Gesellschaft SPG), Brigitte Buchmann (formerly EMPA), Rita Hofmann (formerly BFH), Wolfgang Kroeger (ETH Zurich), Christian Schaffner (ETH Zurich), Karin Schröter (Electrosuisse), Andreas Züttel (EPFL)
This document is available at https://www.satw.ch/en/publications/green-hydrogen-a-contribution-to-the-security-of-supply-and-decarbonisation-of-switzerland
December 2024
Pure hydrogen and its synthesis products can contribute to the decarbonisation of various processes and sectors where direct electrification or other low-carbon solutions are technically or economically difficult to implement. As a chemical energy carrier, hydrogen makes it possible to store electricity from renewable energies and use it for a wide range of applications at a later date.
In order to realise the potential of hydrogen for Switzerland's energy supply, various challenges such as the necessary infrastructure for production, storage and transport must be addressed in a targeted manner and issues relating to use, safety, legislation and standardisation must be clarified quickly. Furthermore, the long-term prospects of a hydrogen economy and the availability of this energy source, particularly for industry, should be examined.
1 What can hydrogen offer Switzerland?
Hydrogen can be used flexibly (illustration 1), transported and stored with suitable infrastructure. If it is produced using renewable energy (so-called "green" hydrogen, see page 6 "Where does hydrogen come from?"), its contribution to the greenhouse effect is small and its use is suitable for substituting fossil fuels and raw materials. The utilisation of green hydrogen in various sectors is currently being researched and is being tested and implemented in a number of pilot projects, including in Switzerland. The following areas of application for hydrogen are considered particularly promising:
1.1 Fuel for mobility (direct use)
The focus here is on freight and long-distance road transport, because the high mass-specific energy density of hydrogen creates advantages in terms of range and transport capacity. For passenger cars and for shorter distances, replacing fossil fuels with battery electric drives is usually more energy-efficient and cost-effective, and many solutions are available on the market. Hydrogen is also being researched and tested as a fuel for shipping, railways and aeroplanes. This enables Switzerland - as the headquarters of several major ocean shipping companies and an important hub in European air transport - to play a role in the innovation and development of hydrogen technologies, to influence them and to benefit from them.
There are currently around 6000 diesel buses on Switzerland's public transport network. Due to climate protection and energy efficiency requirements, these buses are to be replaced by CO2neutral alternatives, specifically by battery and hydrogen buses. A study by the Federal Office of Transport (FOT) shows that hydrogen buses would be suitable for regional transport, where longer and, especially in Switzerland, topographically more challenging routes need to be covered.
1.2 Raw material for synthetic energy sources (conversion)
Together with carbon dioxide, which is collected directly from the air or from point sources (carbon capture), hydrogen can serve as a starting material for the synthesis of gaseous or liquid fuels (e.g. synthetic methane, methanol or other hydrocarbons). Hydrogen is also used in the production of synthetic fuels from vegetable oils or for the production of hydrogen-rich substances such as ammonia. These derivatives are easier to transport and store than hydrogen and offer advantages
because they can often be used to replace fossil fuels with little or no modification to existing infrastructure and machinery.
1.3 Energy source for heat generation and raw material in industry
Hydrogen is a key energy source for providing sufficient quantities of CO2 -neutral high-temperature process heat in industry in the future. Hydrogen is currently used in large quantities as a raw material in the chemical industry, particularly for the production of important basic chemicals such as methanol and synthetic fertilisers. Other important areas of application are the cement industry, steel industry, plastics industry, pharmaceutical industry and food industry. If completely climateneutral hydrogen is used in these industries, this would be a major step towards defossilising production.
1.4 Hydrogen production from renewable energies and storage
Among the chemical energy carriers, hydrogen is the one that can be produced most efficiently from renewable electricity. This makes it an alternative when electricity cannot be used directly or stored in batteries or pumped storage power plants.
Gaseous hydrogen can be stored in pressurised storage tanks with low losses for several months. Hydrogen could therefore also be used in the future to indirectly store electricity at times of high renewable energy generation and low demand and use it instead of fossil fuels for mobility, electricity or heat generation when required (Power-to-X).
For example, by installing electrolysers at the site of renewable electricity production, electricity that is not in direct demand can be used for green hydrogen production. High solar power production in summer could also be used for hydrogen production. Through storage and later reconversion into electricity, hydrogen could contribute in particular to seasonal balancing of the energy supply and possibly also to balancing production and load peaks in the electricity grid.
Hydrogen could also be liquefied for energy storage when cooled to -253 degrees Celsius or stored in metal hydride systems (see example on page 12), as well as being converted into synthetic methane, liquid hydrocarbons or ammonia, which have a higher volumetric energy density (i.e. require a smaller storage volume for the same energy content).
Illustration 1: The production of green hydrogen and its utilisation in various application areas.
2 Why is the question of using hydrogen important and urgent?
The possible applications of hydrogen in mobility, industry and energy supply outlined above can contribute to the goal of achieving CO2 neutrality by 2050 if they are quickly made ready for implementation.
For more than a hundred years, hydrogen produced from fossil resources, and to a lesser extent green hydrogen, has been used in chemical processes in Switzerland. For a few years now, hydrogen produced with renewable electricity has also been used to power a small fleet of hydrogen lorries. The hydrogen is produced in electrolysis plants connected to run-of-river power plants and then distributed to hydrogen refuelling stations by road transport. In summer 2024, 18 such refuelling stations were in operation in Switzerland. The hydrogen is used in lorries and some cars, which convert the hydrogen back into electricity using fuel cells and are powered by electric motors. The fleet has now grown to 50 hydrogen lorries, which have driven a total of over 10 million kilometres in the last 5 years. The current niche application of hydrogen for mobility allows only limited conclusions to be drawn about the possibilities for future hydrogen utilisation in Switzerland. At the end of this document, steps are proposed to enable a broader use of green hydrogen in Switzerland.
Recent energy price fluctuations and geopolitical crises have brought the issue of security of supply to the fore. Replacing fossil fuels with hydrogen could create a better starting position in terms of security of supply. Dependence on natural gas and oil supplies would be greatly reduced or eliminated, but we would be dependent on a high availability of hydrogen production, transport and storage.
Local hydrogen production (illustration 2) can take place in Switzerland from renewable electricity and thus reduce dependence on foreign countries compared to importing fossil fuels, especially in summer, when Switzerland generally produces more electricity than is consumed domestically.
Instead of exporting electricity, it could be stored seasonally in the form of hydrogen and later converted back into electricity or used in industry and mobility. The prerequisites for this are that the necessary infrastructure (electrolysers, storage and transport system) can be built in good time and operated economically in the long term. In the future, electricity from new nuclear power plants could possibly also be used for hydrogen production with low CO2 emissions in Switzerland if the current ban on granting general licences for new nuclear power plants is lifted.
According to a postulate report by the Federal Council from November 2023 on an overview and options for action for Switzerland with regard to hydrogen, demand in Switzerland can probably be met by domestic production until 2035. From 2035 at the latest, it is expected that hydrogen will have to be imported to meet the rising demand. Green hydrogen could be imported from regions with better conditions (e.g. higher solar radiation) for cost-effective large-scale production. However, this requires a connection to a cross-border hydrogen network and international coordination similar to the electricity sector (in particular supply agreements with producer countries) in order to ensure that hydrogen can be imported in sufficient quantity and quality.
Hydrogen can be transported or imported in various forms (gaseous, liquefied or as hydrogen-rich derivatives such as ammonia), whereby liquefaction or conversion into hydrogen derivatives requires additional energy. Various transport infrastructures are also possible (pipelines, road transport by lorry, liquefied gas tankers, etc.), but these need to be built or adapted specifically for hydrogen. The future use of the various transport forms and infrastructures must be assessed on the basis of their energy and technical requirements. In principle, however, the possibilities for diversifying transport would contribute to security of supply.
The implementation of hydrogen systems in Switzerland and the export of corresponding technologies open up a wide range of opportunities for Swiss industry if the corresponding innovations are driven forward and can be brought to market in good time. For example, Swiss companies are developing processes and technologies for the production and storage of hydrogen, as well as propulsion systems for ocean-going vessels or gas turbines that can use hydrogen as a fuel, or are building electrolysis plants. Some examples of applications are presented in this document (see page 11 ff.).
Various organisations, states and communities of states are formulating medium to long-term hydrogen strategies in order to exploit the opportunities offered by hydrogen applications and promote the development of the necessary technologies. A Swiss strategy, which is considered urgent by many players in the hydrogen sector, has been announced by the Federal Administration but has not yet been published. The European Union (EU) already adopted its strategy in 2020, which aims to establish a Europe-wide hydrogen ecosystem. In this context, the development of an international transport network (European Hydrogen Backbone), joint standardisation and various projects along the hydrogen value chain are being promoted as part of EU industrial policy.
3 Where does hydrogen come from?
Hydrogen is the lightest and most common element in the universe. Under normal conditions, hydrogen is present as a molecule in the form of hydrogen gas (H2). Hydrogen gas is non-toxic, colourless and odourless. In terms of its chemical properties, hydrogen is highly reactive and forms compounds with most elements. In terms of mass, hydrogen has the highest energy density of all fuels, but as a gas it requires a large volume for storage (i.e. it has a very low volume-related
energy density). Hydrogen can be burnt to generate heat or electrochemically converted to electricity in a fuel cell by means of redox reactions. In both cases, the product is water.
Hydrogen occurs as geological hydrogen in ferrous rocks, but on Earth it is largely bound with oxygen to form water. Various production processes are used today to obtain pure hydrogen for use in the energy system or as a chemical raw material (Illustration 2). These differ in particular in terms of the energy source used for production and the carbon dioxide emissions (CO2) generated. Depending on the production process, hydrogen is classified according to different colours (the most common classes are described here, but other colour classifications can sometimes be found in the literature):
- "Green" hydrogen is produced either by converting biomass or by electrolysing water with renewable electricity. Production is therefore CO-neutral.2
- "Grey" hydrogen is produced from fossil fuels (steam reformation of natural gas or coal gasification). The resulting CO2 is released into the atmosphere. Currently, most of the hydrogen used worldwide is produced from fossil sources, with significant greenhouse gas emissions.
- "Blue" hydrogen is also produced from fossil fuels, but the CO2 produced is largely captured and stored (carbon capture and storage, CCS).
- "Turquoise" hydrogen is produced through the thermal cracking of natural gas. A large proportion of the CO2 is converted into solid carbon, which can be permanently stored underground.
- "Pink" hydrogen is produced by electrolysis using electricity from nuclear energy.
- "White" hydrogen comes from natural underground deposits.
In principle, hydrogen production can take place in Germany or abroad. Which production processes are suitable at which locations depends primarily on the availability of the required energy sources and raw materials as well as the possibility of storing CO2 or solid carbon underground. Currently, Swiss industry mainly uses grey hydrogen, which is imported from neighbouring countries. According to the International Energy Agency (IEA), annual global hydrogen production is expected to reach almost 100 million tons by the end of 2024, less than one percent of which is produced with low emissions (with CCS). Less than one per thousand of global production comes from water electrolysis, using electricity from both renewable energies and other sources.
In Switzerland, a number of electrolysis plants for the production of green hydrogen are in operation or under construction, often at run-of-river power plants (see example on page 11). In Europe, there are larger electrolysis projects that use electricity from wind farms, for example. According to the IEA, global electrolysis capacity (installed capacity) for hydrogen production almost doubled between 2022 and 2023, with China leading the expansion. With the additional expansion planned for 2024, China is expected to reach almost 70 per cent of global capacity, ahead of Europe with 15 per cent and the United States with 6 per cent.
The rapid expansion of electrolysis plants is also associated with a significantly higher demand for renewable energies if they are to produce green hydrogen in the future. Green hydrogen makes the most effective contribution to decarbonising Switzerland's energy system and achieving the goal of net-zero greenhouse gas emissions. However, hydrogen production with renewable electricity is currently the most expensive; according to the IEA, the costs are 1.5 to 6 times higher than those for "grey" hydrogen without compensation for CO2 emissions, depending on the production site. Other forms of production with low CO2 emissions (such as "blue" or "turquoise" hydrogen)
could support the development of a sustainable hydrogen supply in a transition phase. Depending on the strategy for the future utilisation of nuclear energy in Switzerland, "pink" hydrogen could also be used.
Illustration 2: Colour classification of hydrogen based on production process, energy sources and CO2 emissions.
4 How will hydrogen become important for the Swiss energy supply?
In order to produce and use hydrogen on a large scale in Switzerland, various challenges must be tackled, which are divided into four fields of action below. In many of these areas, it is not yet possible to conclusively assess how important influencing factors will develop and how the costs of introducing hydrogen can be weighed up against its benefits.
4.1 Development of the hydrogen infrastructure and investment security
A comprehensive hydrogen system requires production facilities, systems or networks for transport and distribution, as well as storage facilities. The construction or conversion of existing infrastructures (such as natural gas pipelines and storage facilities) for hydrogen places new and generally higher demands on the materials and technologies used, including with regard to impermeability. The efficiency, benefits and (time) feasibility of different solutions must be weighed up against each other. This applies to road transport versus pipeline networks, various production plants or storage systems for hydrogen or its derivatives (synthetic hydrocarbons or ammonia). The development of infrastructure for hydrogen requires large investments and needs suitable locations where new plants can be built. The acceptance of the new energy source by companies and society also plays a role here, which also has an impact on the willingness to invest and the duration of authorisation procedures.
4.2 Safety and dealing with risks
The high reactivity of hydrogen and thus the risk of fires or explosions must be particularly taken into account here. The gas can also cause metals to become brittle and impair their lifespan. Hydrogen does not act as a greenhouse gas per se, but it does have an indirect negative impact on the climate because it increases the effect of other greenhouse gases. For this reason alone, hydrogen emissions into the atmosphere must be minimised during production, transport and storage. The synthesis product ammonia is reactive, explosive and corrosive. It has the highest hazard potential of the hydrogen derivatives and requires appropriate safety precautions.
4.3 Costs, profitability and competitiveness
Green hydrogen is currently a scarce commodity with high prices and could remain so in the longer term. Driven by costs, this leads to a narrowing of the possible applications of hydrogen and to prioritisation between chemicals, industry, mobility, etc. This is offset by significant progress in electrification, for example in electromobility and battery storage. Whether and to what extent hydrogen should be used for the seasonal storage of renewable energy must also be assessed with regard to the large storage possibilities in Swiss hydropower and the overall efficiency of the conversion processes. A hydrogen storage system must first be established and be able to operate competitively in combination with the existing (pumped) storage hydropower plants and other flexible suppliers, consumers and storage options in the electricity grid (such as batteries for short-term storage). Due to energy losses during hydrogen production and reconversion, the IEA estimates that only around 25-30 per cent of the electricity originally used can ultimately be reused.
4.4 Political framework conditions, regulation and standardisation
The form in which Switzerland is involved in international cooperation on hydrogen, as well as a Swiss strategy for hydrogen supply and storage and its legal anchoring (for example in the Gas Act) are likely to have a strong influence on developments. A legal basis would create the necessary planning security for Swiss companies to commit to the development of hydrogen utilisation. In order to facilitate the construction of hydrogen production plants, the corresponding construction and operating authorisation procedures should be simplified. In relation to Europe, the conditions for connecting Switzerland to a European hydrogen transport network (European Hydrogen Backbone) must be clarified. International transport networks and secured supply contracts with sunny countries and favourable conditions for hydrogen production could enable cost-effective imports of hydrogen. Internationally harmonised technical and safety standards for handling hydrogen could facilitate the use of new hydrogen technologies in Switzerland and the export of Swiss innovations to international markets.
5 How to ensure Switzerland does not fall behind in hydrogen matters?
General recommendations so that hydrogen (and/or its derivatives) can make a significant contribution to Switzerland's future energy system:
- Recognising the relevance of green hydrogen for the future CO2 -neutral Swiss energy system in order to contribute to decarbonisation, security of supply and also economic efficiency (in
certain applications), as well as creating opportunities for Swiss research and innovative companies in the country.
- Use green hydrogen from renewable energies to reduce dependence on fossil fuels as much as possible. In addition, use hydrogen produced with a low climate impact (e.g. "blue" or "pink" hydrogen), depending on Switzerland's future position on carbon capture and the use of nuclear energy.
- Use hydrogen where it offers the greatest benefits in terms of energy and cost efficiency and the reduction of CO2 emissions. Prioritise the use of hydrogen as a raw material and for hightemperature applications in order to minimise greenhouse gas emissions from industry (decarbonisation). In mobility, focus on long-distance and heavy goods transport (possibly also shipping and air transport). Where possible, however, direct electrification should be favoured (e.g. for passenger cars)
- The hydrogen supply in Switzerland must be developed as an overall system that includes production, storage and transport infrastructure. The development must be internationally embedded in the transformation of the entire energy system and aligned with the demand for hydrogen (for energy supply and industry). The potential contribution of hydrogen to the seasonal storage of electricity from renewable energy sources must also be taken into account.
Relevant players in Switzerland can contribute to the development of hydrogen utilisation in the following ways:
5.1
Research and development
- Demonstrate possible applications of hydrogen from an overall system perspective, as well as feasibility and efficiency. In particular, clarify the suitability and potential of hydrogen as a (seasonal) storage medium in Switzerland. Estimate the medium- and long-term demand expected and identify ways of meeting this demand.
- Comprehensive assessment of the advantages and disadvantages, including sustainability and costs, of hydrogen and its synthesis materials (SWOT analyses).
- Advancing technology development and materials research for electrolysers, storage systems, transport systems, combustion units and fuel cells.
5.2
Swiss industry and associations
- Develop concepts and implement pilot projects to promote the use of green hydrogen with successful application examples in Switzerland, e.g. realising production plants and industrial applications.
- Transferring existing expertise from the development of high-tech components, the mechanical engineering industry (power plants, turbines, engines) or as an automotive supplier to the hydrogen economy.
5.3
Regulators and administration
- Pursue chemical energy sources with a view to developing synthetic alternatives to fossil fuels.
- Clarify framework conditions and political measures for infrastructure development (and, if necessary, its promotion), the development of a hydrogen network (including international
connections) and safety, and remove any administrative hurdles. Publish a corresponding roadmap for the Swiss hydrogen strategy.
- Develop and update standardisation based on international standards.
6 Swiss application examples for hydrogen utilisation
6.1 Electrolysis plants for hydrogen production
Axpo and Rhiienergie currently operate the largest production plant for green hydrogen in Switzerland at the Reichenau hydropower plant in Domat/Ems, Graubünden, with an annual production of up to 350 tonnes. The gas is highly compressed in the plant and delivered by lorry to customers who use it for fuel cell trucks or high-temperature processes in industry. Three other Swiss electrolysis plants also produce green hydrogen using hydropower. In addition, almost ten other projectssome with significantly greater output - are known to be in the planning or realisation stage.
https://www.axpo.com/ch/de/energy/generation-and-distribution/hydrogen/reichenau.html
6.2
Engines for ocean-going shipping
The Swiss company WinGD emerged from Sulzer and is now one of the global market leaders in combustion engines for large merchant ships and is developing them further for synthetic fuels. Today, international shipping is responsible for over 2 per cent of global anthropogenic CO2 emissions. In the foreseeable future, pure hydrogen will not play a significant role as a fuel in ocean shipping and a mix of different synthetic energy sources (such as synthetic methane, methanol or ammonia), which are produced using green hydrogen, is more likely to prevail as a replacement for fossil heavy fuel oil and liquid gas. The first ship engines that can use ammonia as a fuel should be ready for delivery from 2025.
https://www.wingd.com/en/technology-innovation/environmental-technologies/development-forclean-liquid-fuels/
6.3 Gas turbines for electricity production
The Italian technology company Ansaldo Energia - with a Swiss subsidiary and test facilities in Birr, Aargau - took over part of ABB's gas turbine development activities in Baden in 2016. The company is further developing gas turbines for electricity production, which are currently operated with natural gas, for operation with hydrogen as fuel. Successful tests suggest that the systems will be ready for the market by 2030.
https://www.ansaldoenergia.com/know-how-enablers/research-development-1
6.4
Storage and compressors for hydrogen based on metal hydrides
Gruyère Energie SA in Bulle produces hydrogen by electrolysis using renewable electricity from hydropower and stores it in a metal hydride storage facility developed and built by GRZ Technologies. This Swiss company in Avenches develops and sells storage tanks and compressors for hydrogen
based on metal hydrides. In metal hydrides, more hydrogen atoms can be stored in the same volume than in liquefied hydrogen without cooling and at low overpressure.
The safe and compact metal hydride storage tanks can also be used in densely populated areas because there is no risk of explosion. The GRZ hydrogen compressor compresses the hydrogen directly into a tank or lorry trailer, without pressure cascades and using only thermal energy. These highly efficient, safe and compact compressors do not generate any disruptive noise emissions or vibrations during operation. Messer Schweiz AG in Lenzburg uses a hydrogen refuelling station with a metal hydride compressor to refuel forklift trucks. This system was developed by GRZ together with Messer.
https://www.gruyere-energie.ch/news/inauguration-de-gruyere-hydrogen-power-sa-2147
https://grz-technologies.com/
https://www.messer.ch/wasserstofftechnologien
About the SATW and its Energy Group
The Swiss Academy of Engineering Sciences SATW is the most important network of experts in the field of engineering sciences in Switzerland and is in contact with the highest Swiss bodies for science, politics and industry. The network consists of elected individual members, member organisations and experts. The SATW identifies industrially relevant technological developments on behalf of the Swiss Confederation and informs politics and society about their significance and consequences. As a unique specialist organisation with a high level of credibility, it provides independent, objective and comprehensive information on technology - as a basis for forming well-founded opinions. The SATW also promotes interest in and understanding of technology among the general public, especially young people. It is politically independent and non-commercial.
In the Energy Group, experts from the SATW network deal with current issues and new technologies for the transformation of the energy system in Switzerland. These topics are documented in a series of publications or discussed at events with other experts. In spring 2024, the SATW held a discussion forum on applications of hydrogen and synthetic energy sources for mobility, decarbonisation and energy storage. Future developments in hydrogen and the associated challenges for Switzerland will be followed up by SATW and, if necessary, accompanied by further events and publications.