LargeTESModelingToolkit: A Modelica Library for Large-scale Thermal Energy Storage Modeling and Simulation


  • Michael Reisenbichler-S.
  • Franz Wotawa
  • Keith O’Donovan
  • Carles Ribas Tugores
  • Franz Hengel



Modelica library, Large-scale thermal energy storage, Pit TES, Tank TES


This paper introduces the LargeTESModelingToolkit, a novel Modelica library for modeling and simulation of large-scale pit and tank thermal energy storage. This first comprehensive Modelica library in the field provides the flexibility and tools needed to develop new storage models tailored to the desired application. It also offers researchers and industrial users pre-built storage models for simulation studies to answer the relevant questions for an optimized design at storage and system level. In this paper we present the library’s key features and structure, and introduce the underlying physical and mathematical foundations and modeling approaches. Moreover, we discuss the validation of the models, present the first results, and show the library’s applicability using an exemplary simulation case study.