The energy transition is fundamentally changing the electricity system. Periods of low wind and low sunlight make it clear that renewable energies alone cannot guarantee security of supply. This masterclass examines the four key building blocks of a resilient system: firstly, the electricity grid as the physical backbone, which is facing its biggest ever overhaul, requiring several hundred billion euros in investment. Secondly, controllable power stations – in particular H₂-capable gas-fired power stations – as an indispensable backup in a system dominated by renewables. Thirdly, battery storage, whose rapid fall in price is opening up new possibilities without overcoming the physical limitations of seasonal storage. Fourthly, demand flexibility through smart consumers, variable tariffs and dynamic grid charges – the sleeping giant of the energy transition. Markets link these building blocks as a coordination and investment mechanism. Security of supply is achievable – but it won’t happen by itself.

Dr Marius Buchmann has been advising energy suppliers, grid operators and government departments on regulation, market design and the energy transition for 15 years. Key areas of expertise: incentive-based regulation, CO₂ infrastructure, district heating networks and hydrogen. Currently a Research Fellow at the Oxford Institute for Energy Studies.

The debate on the hydrogen market in Germany has its roots in climate policy – yet its importance for security of supply is often underestimated. In an energy system increasingly characterised by volatile renewable energy sources, hydrogen plays a central role in the storage, transport and temporal decoupling of energy supply and demand. Hydrogen storage, in particular, enables the seasonal storage of large quantities of energy and can bridge supply gaps during periods of low solar and wind output. At the same time, hydrogen infrastructure and domestic production strengthen the resilience of the energy system and reduce geopolitical dependencies. The Master Class examines the systemic role of hydrogen across the entire value chain – from electrolysis and imports, through transport and storage, to its use in industry and power stations – and discusses the contribution hydrogen can make to security of supply during the energy transition.

Dr.-Ing. Geert Tjarks has been Managing Director of EWE HYDROGEN GmbH since January 2024; the company is responsible for EWE AG’s hydrogen production. He also worked at EWE GASSPEICHER GmbH as Head of Hydrogen Business Development, where he was responsible for the business strategy for hydrogen as well as for the political and economic networks required to implement this strategy at EWE AG.
Prior to this, he spent four years at the National Organisation for Hydrogen and Fuel Cell Technology – NOW GmbH in Berlin, where he was responsible for international cooperation and represented the German government in various international multilateral bodies for hydrogen technologies. In 2019 and 2020, he supported the German government in developing the national hydrogen strategy. In January 2017, he completed his PhD at RWTH Aachen University, specialising in water electrolysis systems.

A mission statement for the energy system of the future is important because it provides guidance for all stakeholders. It defines goals and values and offers a framework for a sustainable, secure and affordable energy supply. It also promotes cooperation between politics, business, academia and society, and ensures balanced development from an environmental, economic and social perspective. As part of the Master Class, a mission statement will be presented on the basis of a series of propositions. Project examples demonstrate that the transformation is already underway and highlight areas where further action is needed.

Dr Alexander Bedrunka heads the Energy Systems and Infrastructure division at the Lower Saxony Climate Protection and Energy Agency. For more than five years, he has been advising and supporting policymakers, industry and academia in accelerating the transition towards a climate-friendly and sustainable energy system. Together with his team, he analyses current challenges and, building on these, develops well-founded perspectives for sustainable system development.

This masterclass explores the vision of a just energy system. Using the example of offshore wind expansion as part of the energy transition, the perspectives and ideas of various societal stakeholders will be discussed. How can effective solutions be designed for the energy transition that ensure distributive justice, procedural justice and recognition justice?

Offshore wind provides a good example for illustrating the complexity of the energy transition. The majority of offshore wind expansion takes place far out at sea and is barely visible, if at all, from land. Nevertheless, the regions along the North Sea coast are affected by its impacts. Cable landings, grid expansion, as well as harbour extensions and infrastructural changes encroach upon natural and social habitats, and these impacts must be negotiated in light of a wide variety of objectives and values. It is not uncommon for climate protection and nature conservation, in particular, to find themselves in conflict with one another in this context.

In the Master Class, participants will learn about various aspects of energy justice and will work together to develop and discuss different visions for a just energy transition.

Dr Sophie Berg conducts research and teaches as a postdoctoral researcher at the Chair of Ecological Economics at the University of Oldenburg and carries out research as a research assistant in the TEN.efzn research network within the sub-project ‘70 GW Offshore Wind Real-World Laboratory’.
In 2025, Sophie Berg was awarded the University of Oldenburg’s Teaching Prize for the seminar she leads, ‘Decisions under Uncertainty: Making Sustainability Dilemmas Tangible through Play’.