Implementation and verification of the IDEAS building energy simulation library

TLDR

Building and district energy systems are becoming increasingly complex, demanding accurate simulation and optimization of integrated multi‑physics components, yet existing tools lack transparency and flexibility, whereas equation‑based platforms like Modelica enable solver interchangeability. The authors developed the Integrated District Energy Assessment by Simulation (IDEAS) library and provide a comprehensive, well‑documented overview of its building‑system component. IDEAS introduces new computational features, enhanced usability, and an updated BESTEST intercomparison to support detailed, multi‑zone modeling. Verification against IEA EBC Annex 58 confirms the library’s accuracy.

Abstract

Building and district energy systems become increasingly complex, requiring accurate simulation and optimization of systems that combine building envelope, heating ventilation and air conditioning, electrical distribution grids and advanced controllers. Hence, it becomes more challenging for existing simulation tools to provide integrated solutions for these multi-physics problems. Moreover, common building simulation frameworks tightly integrate model equations and their solvers in the program code, which affects model transparency and hampers tool extensions. This is contrasted by equation-based tools such as Modelica, for which different solvers can be used. In this context, the Integrated District Energy Assessment by Simulation (IDEAS) library is developed. After a recent development shift towards more detailed, multi-zone models, this paper presents a comprehensive, well-documented, overview of the buildings part of IDEAS. This includes new computational aspects of the library, improved usability aspects, an updated intercomparison with BESTEST and a verification based on IEA EBC Annex 58.