Solar assisted district heating system with seasonal thermal energy. storage in Eggenstein-Leopoldshafen

F. Ochs1*, J. NuBbicker-Lux1, R. Marx1, H. Koch2, W. Heidemann1, H. MBller-Steinhagen1, 3

1 Institute of Thermodynamics and Thermal Engineering, Pfaffenwaldring 6, 70569 Stuttgart, Germany
2 Pfeil und Koch Ingenieurgesellschaft mbH PKi, Stuttgart, Germany
3 DLR Stuttgart, Institute of Technical Thermodynamics
* Corresponding Author, email: ochs@itw. uni-stuttgart. de

Abstract

The solar assisted district heating system with seasonal thermal energy storage in Eggenstein-Leopoldshafen (Germany) is the first system realized with existing renovated buildings. The system consists of 1600 m2 flat plate collectors and a 4500 m3 gravel-water thermal energy store (TES) for seasonal thermal storage. Experiences gained within the BMU-project “Further development of the pit heat store technology” contributed to the design of the seasonal TES. This paper focuses on the design and construction of the gravel — water store. The monitoring concept of the solar assisted district heating system with focus on the gravel-water TES is presented.