Germany should not become too dependent on other countries for clean energy resources. This is the demand made by the members of the Kopernikus project Ariadne. Among them is Würzburg economist Joschka Wanner.
On Monday, December 1, 2025, the members of the Kopernikus project Ariadne, funded by the Federal Ministry of Research, Technology, and Space, presented their new report. In it, they establish for the first time links between political measures and specific market failures for clean energy goods. They demand that Germany should not become too dependent on countries whose market shares in this area are growing - above all China. The gas crisis following Russia's attack on Ukraine has shown how damaging this can potentially be.
Green Technologies are Important for Economic Growth
According to the authors, clean energy goods, i.e., technologies such as solar modules and the rare earth elements needed to manufacture them, will be important not only for climate protection but also for economic growth in the future. "In 2023, clean energy goods accounted for ten percent of global gross domestic product growth. Germany must therefore learn from its dependence on Russian gas and not allow itself to become dependent on China for green technologies in the future," explains Ariadne researcher Michael Jakob from Climate Transition Economics. According to him, global import dependencies threaten the local market - especially when imports of a good or technology from a few countries or just one country account for a high proportion of total domestic consumption.
The report was compiled by scientists from Climate Transition Economics, the Potsdam Institute for Climate Impact Research, the Joint Research Centre of the European Commission, the Center for Energy and Environmental Policy Research, and the Julius-Maximilians-Universität Würzburg. They show how import dependencies differ for different goods.
A Policy Mix of Various Measures
The researchers differentiate between market failures that lead to insufficient domestic production and those that result in insufficient diversification and thus insufficient resilience. The former includes, for example, the concentration of production in a few locations because unit costs are lower for higher volumes. E.g. due to path dependencies, the concentration does not necessarily take place in the most efficient locations. The latter is due, for example, to information and coordination problems within the supply chain. In addition, companies invest too little in precautionary warehousing and diversified supply chains because they expect the state to step in during times of crisis.
To support domestic production, diversification and resilience of companies in the green technology market environment, the researchers are investigating the effects of various policy measures. They consider financial support, research, and infrastructure development as a means of strengthening domestic production.
Government-guaranteed minimum purchase quantities or government-financed reserve capacities can ensure a minimum supply on the domestic market. To avoid supply bottlenecks for goods that are crucial in the short term, such as energy and rare earth elements, the authors recommend strategic reserves in larger quantities. However, such reserves are less suitable for components such as microchips due to their high degree of specialization and rapid depreciation.
Warning against General Trade Restrictions
The researchers warn against general trade restrictions. Although these are an obvious way to protect domestic manufacturers from foreign competition, they increase the cost of imported goods. Trading partners may also respond with their own trade barriers.
The demand for imported goods can be reduced by establishing a circular economy. In addition, the researchers propose trade quotas and staggered tariff quotas to ensure that imports from a single country remain below a set threshold. This interferes with free trade and competition as little as possible, can be implemented without additional tax revenue, and at the same time avoids excessive dependencies.
"Tariff quotas have been introduced for electric and hybrid vehicles in Brazil, for example. If imports from a single trading partner exceed the set quota, a higher tariff rate applies to all additional imports from that country," explains co-author Joschka Wanner, junior professor of Quantitative International and Environmental Economics at the University of Würzburg.
Stress Test along the Supply Chain
Furthermore, given the complexity of supply chains, the authors argue that it is important for companies to have a knowledge base about their suppliers' subcontractors. This is the only way to respond appropriately to disruptions along the supply chain. Stress tests, such as those carried out in the financial sector, can serve as a model here.
The report makes it clear that measures against import dependency on clean energy goods often only indirectly target market failure and do not fundamentally avoid dependencies. To prevent Germany from becoming dependent on new imports in the future, it should therefore equip itself with a mix of instruments that address market failure as specifically as possible without excessively restricting international trade.
Publication
Michael Jakob, Matthias Kalkuhl, Robert Marschinski, Michael Mehling, Joschka Wanner (2025): Importabhängigkeit bei sauberen Energiegütern - Marktversagen und Politikinstrumente. Kopernikus-Projekt Ariadne, Potsdam. https://doi.org/10.48485/pik.2025.28
Website Ariadne Project
