TY - JOUR A1 - Sterner, Michael A1 - Specht, Michael T1 - Power-to-Gas and Power-to-X-The History and Results of Developing a New Storage Concept JF - Energies N2 - Germany's energy transition, known as 'Energiewende', was always very progressive. However, it came technically to a halt at the question of large-scale, seasonal energy storage for wind and solar, which was not available. At the end of the 2000s, we combined our knowledge of both electrical and process engineering, imitated nature by copying photosynthesis and developed Power-to-Gas by combining water electrolysis with CO2-methanation to convert water and CO2 together with wind and solar power to synthetic natural gas. Storing green energy by coupling the electricity with the gas sector using its vast TWh-scale storage facility was the solution for the biggest energy problem of our time. This was the first concept that created the term 'sector coupling' or 'sectoral integration'. We first implemented demo sites, presented our work in research, industry and ministries, and applied it in many macroeconomic studies. It was an initial idea that inspired others to rethink electricity as well as eFuels as an energy source and energy carrier. We developed the concept further to include Power-to-Liquid, Power-to-Chemicals and other ways to 'convert' electricity into molecules and climate-neutral feedstocks, and named it 'Power-to-X'at the beginning of the 2010s. KW - 100% renewable energy scenarios KW - CARBON RECYCLING SYSTEM KW - CO2 KW - eFuels KW - electric fuels KW - energy transition KW - hydrogen KW - methanation KW - METHANOL KW - Power-to-Gas KW - Power-to-Hydrogen KW - Power-to-Methane KW - Power-to-X KW - sector coupling KW - sectoral integration KW - TRANSPORTATION Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-26202 N1 - Corresponding author: Michael Sterner VL - 14 IS - 20 PB - MDPI ER - TY - GEN A1 - Sterner, Michael T1 - Power-to-X for Europes Energy Transformation – Booster H2Global T2 - Hydrogen Online Workshop Conference (Mission Hydrogen), 25.03.2021 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2021 ER - TY - GEN A1 - Sterner, Michael T1 - Ohne Speicher, Wasserstoff und Power-to-X keine Dekarbonisierung von Verkehr und Industrie – Möglichkeiten und Notwendigkeit der integrierten Sektorenkopplung T2 - CIGRE/CIRED Informationsveranstaltung 2020, Leipzig, 13.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Klimaschutz KW - Energiespeicher KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Megathema Wasserstoff: Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland T2 - IRES Symposium, Berlin 18.11.2020 KW - Erneuerbare Energien KW - Wasserstoff KW - Klimaneutralität KW - Power-to-X KW - Energiewende KW - Sektorenkopplung Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland T2 - Hydrogen Dialogue H2.Bayern, 18.11.2020, Nürnberg Friedrich-Alexander-Universität KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - The role of green H 2 + Power-to-X in the German Energy Transition T2 - First Brazilian-German Green Hydrogen Congress, Brasilia 06.10.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Wasserstoff KW - Power-to-X Y1 - 2020 ER - TY - GEN A1 - Sterner, Michael T1 - Warum wir Power-to-X für die Klimaneutralität und Mobilitätswende brauchen T2 - DECHEMA Fachforum Diesel: Mobilitätswende durch alternative Antriebe und Kraftstoffe:, Frankfurt 02.12.2020 KW - Erneuerbare Energien KW - Klimaneutralität KW - Energiewende KW - Sektorenkopplung KW - Power-to-X Y1 - 2020 ER - TY - JOUR A1 - Sterner, Michael A1 - Bauer, Franz T1 - Power-to-X im Kontext der Energiewende und des Klimaschutzes in Deutschland JF - Chemie-Ingenieur-Technik N2 - Um den Einfluss verschiedener Power-to-X-Verfahren auf die Transformation des deutschen Energiesystems und das Erreichen der Klimaschutzziele zu überprüfen, wurde ein sektorübergreifendes Energiesystemmodel entwickelt. Die daraus gewonnenen Ergebnisse zeigen: Für eine erfolgreiche Energiewende ist der Einsatz von Power-to-X in Zukunft unverzichtbar. Vor allem in Bereichen und Sektoren, in denen hohe Energiedichten erforderlich und nur wenig andere Optionen zur Defossilisierung vorhanden sind, werden Power-to-X-Technologien zwingend notwendig. T2 - Power-to-X in Context of Energy Transition and Climate Change Mitigation in Germany KW - Power-to-Gas KW - Climate mitigation KW - Energy system KW - Modeling KW - Power-to-X KW - Klimaschutz KW - Energiewende Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-11669 SN - 0009-286X N1 - Corresponding author: Franz Bauer VL - 92 IS - 1-2 SP - 85 EP - 90 PB - Wiley ER - TY - JOUR A1 - Sterner, Michael A1 - Hofrichter, Andreas A1 - Meisinger, Alexander A1 - Bauer, Franz A1 - Pinkwart, Karsten A1 - Maletzko, Annabelle A1 - Dittmar, Felix A1 - Cremers, Carsten T1 - 19 Import options for green hydrogen and derivatives - An overview of efficiencies and technology readiness levels JF - International Journal of Hydrogen Energy N2 - The import of hydrogen and derivatives forms part of many national strategies and is fundamental to achieving climate protection targets. This paper provides an overview and technical comparison of import pathways for hydrogen and derivatives in terms of efficiency, technological maturity and development and construction times with a focus on the period up to 2030. The import of hydrogen via pipeline has the highest system efficiency at 57-67 % and the highest technological maturity with a technology readiness level (TRL) of 8-9. The import of ammonia and methanol via ship and of SNG via pipeline shows efficiencies in the range of 39-64 % and a technological maturity of TRL 7 to 9 when using point sources. Liquid hydrogen, LOHC and Fischer-Tropsch products have the lowest efficiency and TRL in comparison. The use of direct air capture (DAC) reduces efficiency and TRL considerably. Reconversion of the derivatives to hydrogen is also associated with high losses and is not achievable for all technologies on an industrial scale up to 2030. In the short to medium term, import routes for derivatives that can utilise existing infrastructures and mature technologies are the most promising for imports. In the long term, the most promising option is hydrogen via pipelines. KW - Hydrogen KW - Derivatives KW - Power-to-X KW - Efficiency KW - TRL KW - Construction time KW - Technical assessment KW - Import KW - Hydrogen strategy KW - Energy system modelling Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-77756 SN - 0360-3199 N1 - Corresponding author der OTH Regensburg: Michael Sterner VL - 90 SP - 1112 EP - 1127 PB - Elsevier ER - TY - INPR A1 - Meisinger, Alexander A1 - Hofrichter, Andreas A1 - Bauer, Franz A1 - Sterner, Michael T1 - Unlocking Potential Energy Partnerships in Europe: a Case Study on the Way to a Franco-German Energy Transition N2 - Global warming is already causing global destabilization. Geopolitical challenges fuel this instability and highlight the need for trusted energy partnerships to ensure energy security. To limit global warming and increase energy security, it is essential to take joint action on an international and global scale. The European Green Deal contributes to this. However, specific national actions are still needed. This research presents a way forward for a Franco-German energy transition and unlocks the potential of energy partnerships within Europe, using a cost-based, sector-coupled optimization model. Both countries are coupled via an isolated country optimization approach. Thus, the focus is on the development of each national energy system. The results highlight the increase of energy security in line with the European Green Deal. The main pillars of the energy transition are solar energy (32- 33%), wind energy (25-38%) and biogenic energy sources (13-27%). Nuclear power is being phased out in Germany and France. The results show that a Franco-German energy partnership has great potential. Overall, France can cost-effectively cover 25% of Germany’s hydrogen import needs (122 TWh) in 2050. At the same time, France can also benefit from the energy partnership in terms of economic growth and joint action to mitigate climate crisis. KW - Decarbonization KW - Energy partnership KW - Energy system modelling KW - Energy transition KW - European Green Deal KW - Power-to-X Y1 - 2025 U6 - https://doi.org/10.2139/ssrn.5251699 PB - SSRN ER - TY - INPR A1 - Schumm, Leon A1 - Abdel-Khalek, Hazem A1 - Brown, Tom A1 - Ueckerdt, Falko A1 - Sterner, Michael A1 - Fioriti, Davide A1 - Parzen, Max T1 - The impact of temporal hydrogen regulation on hydrogen exporters and their domestic energy transition N2 - As global demand for green hydrogen rises, potential hydrogen exporters move into the spotlight. However, the large-scale installation of on-grid hydrogen electrolysis for export can have profound impacts on domestic energy prices and energy-related emissions. Our investigation explores the interplay of hydrogen exports, domestic energy transition and temporal hydrogen regulation, employing a sector-coupled energy model in Morocco. We find substantial co-benets of domestic climate change mitigation and hydrogen exports, whereby exports can reduce domestic electricity prices while mitigation reduces hydrogen export prices. However, increasing hydrogen exports quickly in a system that is still dominated by fossil fuels can substantially raise domestic electricity prices, if green hydrogen production is not regulated. Surprisingly, temporal matching of hydrogen production lowers domestic electricity cost by up to 31% while the effect on exporters is minimal. This policy instrument can steer the welfare (re-)distribution between hydrogen exporting firms, hydrogen importers, and domestic electricity consumers and hereby increases acceptance among actors. KW - Energy Transition KW - Hydrogen regulation KW - Hydrogen export KW - Climate-neutral KW - Domestic prices KW - Hydrogen prices KW - Power-to-X Y1 - 2024 U6 - https://doi.org/10.21203/rs.3.rs-4285425/v1 N1 - Der Aufsatz wurde peer-reviewed veröffentlicht und ist ebenfalls in diesem Repositorium verzeichnet unter: https://opus4.kobv.de/opus4-oth-regensburg/8485 PB - Research Square Platform LLC ER - TY - JOUR A1 - Schumm, Leon A1 - Haas, Jannik A1 - Peer, Rebecca A1 - Sterner, Michael T1 - The role of hydrogen offtaker regulation in highly renewable electricity systems JF - Energy N2 - The growing demand for green hydrogen necessitates a rapid scale-up of production and exports to meet decarbonization targets globally. However, current ramp-up efforts remain insufficient, calling for policies that unlock the potential of hydrogen as a low-carbon energy carrier. A key lever is the offtaker regulation, which impacts the pace and sustainability of export projects. This study investigates minimum renewable share requirements for hydrogen exports in countries with high renewable electricity shares. Using New Zealand as a case study, we develop a fully sector-coupled capacity expansion and dispatch model, integrating hydrogen and electricity network planning based on PyPSA-Earth. The model optimizes New Zealand’s energy system under varying export scenarios, renewable electricity shares, and resulting system impacts. We find that domestic electricity demand and renewable expansion rates dominate long-term outcomes, while progressive regulation enables short-term hydrogen and Power-to-X exports. Relaxing the renewable threshold from 80% to 60% triples export volumes from 2.5 TWh to 8.2 TWh by 2030. We propose a two-stage requirement: an initially progressive threshold to attract investment with low consequential emissions, followed by stricter regulation to prevent high emissions, rising domestic electricity prices, and declining hydrogen competitiveness. This framework, demonstrated for New Zealand, can guide hydrogen-exporting countries worldwide. KW - Climate neutrality KW - e-fuels KW - Emission intensity KW - Energy systems modelling KW - Hydrogen exports KW - Hydrogen offtaker regulation KW - Power-to-X Y1 - 2026 U6 - https://doi.org/10.1016/j.energy.2025.139513 N1 - Corresponding author der OTH Regensburg: Leon Schumm VL - 342 PB - Elsevier ER - TY - INPR A1 - Achhammer, Anton A1 - Fioriti, Davide A1 - Patonia, Aliaksei A1 - Sterner, Michael T1 - The impact of hydrogen underground storage on fair partnerships: a GIS-based integration of salt caverns into PyPSA-Earth N2 - The increasing demand for hydrogen in Europe and the development of cross-border infrastructure, such as the SoutH2 Corridorconnecting Tunisia, Italy, Austria, and Germany, underscore the importance for hydrogen storage solutions to ensure supplysecurity and competitive pricing. Without storage, producers face increased market dependency, as electrolyzers require con-tinuous operation to remain economically viable. At the same time, storage offers opportunities to strengthen domestic valuechains by securing hydrogen supply for local industries. To assess the system-level impact of underground hydrogen storageand its implications for hydrogen partnerships, we integrate GIS-based salt cavern potentials into PyPSA-Earth and apply theframework to Tunisia. Salt caverns are currently largely considered the most economical option for large-scale hydrogen storage,offering operational flexibility. Underground storage is represented as an endogenously optimised, regionally constrained option,enabling a direct comparison between scenarios with and without geological storage under identical demand, technology, andpolicy assumptions.Our results show that underground hydrogen storage enables seasonal balancing at multi-terawatt-hour scale, reshaping hydro-gen system design. Storage availability substitutes most aboveground hydrogen tank capacity, improves electrolyser utilisation,and reduces levelised hydrogen production costs by approximately 0.10 € kg−1. Moreover, it decouples hydrogen production fromshort-term electricity variability and export demand, enhancing supply stability and export competitiveness.Beyond the Tunisian case, the findings underscore the strategic role of geological storage in international hydrogen trade. Byincreasing resilience and reducing cost volatility, underground hydrogen storage strengthens the position of exporting regionsand supports more balanced and sustainable hydrogen partnerships. KW - Energy Transition KW - Hydrogen export KW - hydrogen underground storage KW - Hydrogen prices KW - salt caverns KW - Power-to-X KW - PyPSA-Earth Y1 - 2026 U6 - https://doi.org/10.2139/ssrn.6307406 PB - SSRN ER -