01.2022 - 05.2023

Circular Energy Transition

The expansion of renewable energies, storage facilities and grid components enables the energy transition. However, this also consumes valuable resources. How can the circular economy (CE) contribute to minimising resource consumption and thus ensure sustainable transformation of the energy system? Which methods are needed to consistently account for the savings of emissions and raw materials over the entire life cycle? These are the questions addressed by the project Kreislauffähige Energiewende (circular energy transition).


The implementation of the energy transition requires an expansion of renewable energies, storage technologies and grid infrastructure. This transformation towards a low-emission energy system is associated with a high demand for materials. In addition to conventional materials such as copper and steel, critical materials such as rare earths are also needed for this. The extraction, transport, processing and disposal of these raw materials and materials is associated with greenhouse gas (GHG) emissions. These emissions can be reduced by implementing a circular economy (CE). Furthermore, circular economy measures such as recycling, life extension, waste avoidance or reuse can also save resources.

The prerequisite for this is that companies increasingly implement such circular economy measures. As part of the Green Deal, the EU has adopted a Circular Economy Action Plan. This requires companies to report on greenhouse gases, which in future should also include the effects of circular economy measures. There are already methods available today, such as Life Cycle Assessment (LCA), which can be used to calculate emissions over the entire life cycle, or simple tools for companies that support the calculation of emissions in the area of resource efficiency (project ESTEM).


Project Objectives

Figure 1 shows an example of which circular economy measures can be applied in the life cycle of a photovoltaic system.

Figure 1: Illustration of possible CE measures in the photovoltaic life cycle. Own illustration based on [1] and [2]

But which greenhouse gas emissions and materials can be saved by implementing the measures?

This question is being investigated in the project “circular energy transition: Balancing the reduction of greenhouse gases through future material cycles in the life cycle of energy technology systems and components” (in short: Kreislauf E-Wende). Future developments of both the energy system itself and the circular economy, e.g. with regard to the development of new recycling technologies, are taken into account. The focus is on the following tasks:

  • Development of procedures for methodological questions of LCA for the balancing of greenhouse gas emissions in future material cycles of the circular economy.
  • Analysis of the future implementation of components and plants in the energy system against the background of the transformation to renewable energies.
  • Development of scenarios of future recycling technologies and analysis of the resulting substitution potentials for primary raw materials.

The methods developed will be tested and evaluated in a pilot application of the project partner Siemens Energy, whose expertise and data stocks on selected energy technology plants will be incorporated into the development of data sets.

Project Structure

The tasks are divided into four work packages, each of which is being led by a consortium partner:

As a result of the project, practice-relevant methods for balancing the impacts of circular economy measures will be developed. The tools have a high practical relevance for companies, for example with regard to the upcoming requirements of the EU taxonomy regulation, as well as for politics, for example with regard to the determination of so-called break-even points for the upgrading or renewal of plant stocks in the energy system. In addition, calculations will be implemented in the project itself in order to provide initial substantive findings on the climate relevance of circular economy measures in the energy system.

Project Partners and Funding

The project started in January 2022, runs until the end of 2024 and is funded by the Bundesministerium für Wirtschaft und Klimaschutz (BMWK) (funding code 03EI5002C). Other project partners are the SuR department at the University of Darmstadt, Pforzheim University of Applied Sciences and Siemens Energy AG.


[1] Deng, Rong (2021): End-of-life recycling of silicon photovoltaic modules: towards a circular economy; https://doi.org/10.26190/unsworks/22807

[2] P. Lacy, J. Keeble, R. McNamara, J. Rutqvist, K. Eckerle, T. Haglund, P. Buddemeier, M. Cui, A. Sharma, A. Cooper, T. Senior and C. Pettersson. Circular Advantage – Innovative 116 Business Models and Technologies to Create Value in a World without Limits to Growth. Dublin: Accenture, 2014