ZEE Miniworkshop on Seasonal Thermal Energy Storage

Tuesday, July 07, 2026, 13:30 - 17:30

Room 01-012, Georges-Köhler-Allee 102, Freiburg 79110, Germany

This mini workshop aims to identify open research questions and explore opportunities for a joint research proposal on Seasonal Thermal Energy Storage (STES). The discussion will focus on optimization-based operation and control strategies for STES systems, enabling the efficient integration of renewable heat sources into future energy systems. By storing surplus thermal energy generated during summer and utilizing it in winter, STES can significantly increase the share of renewable heat while improving system flexibility, efficiency, and resilience. 
 
Speakers:
  • Prof. Dr. Moritz Diehl, University of Freiburg
  • Steffen Herrbach-Claussen, Wärmeinfrastruktur Meldorf GmbH und Co KG
  • Jaßper Weichmann, Fraunhofer IEG
  • Wonsun Song, greenventory GmbH
  • Manuel Kollmar, Hochschule Karlsruhe, University of Freiburg
 
Preliminary Timetable:
13:15 – 13:30
 Arrival & Coffee
13:30 – 13:40
 Introduction of All Participants
13:45 – 14:00
 The Role of STES in the Energy System of the Future (Moritz Diehl)
14:00 – 14:15
 The Seasonal Storage in Meldorf (Steffen Herrbach-Claussen, online, including questions)
14:15 – 14:30 Operational optimization of a Geothermal Probe Storage Tank for Industrial Cooling. Challenges and Approaches from our Practical Experience (Jaßper Weichmann)
14:30 – 14:45 
From Municipal Heat Planning to Simulation and Control of Heating Systems with Seasonal Heat Storage (Wonsun Song)
14:45 – 15:00 Optimal Operation of a Fifth-Generation District Heating and Cooling Network with Seasonal Ice Storage via Nonsmooth Model Predictive Control: A Real-Network Case Study (Manuel Kollmar)
15:00 – 15:30
 Brainstorming on Research Gaps in the Optimization and Control of STES
15:30 – 16:00
 Coffee Break and Group Photo
16:00 – 17:00
 Discussion on the Roadmap for a Project Proposal
~ 17:00
 Wrap-Up