Developing a simplified methodology for simulating energy performance of buildings with thermally activated building systems

Abstract

Detailed building models allow the HVAC designers to find optimal solutions. However, more complexity in modelling will also result in more efforts for the designers in the component sizing procedure specially when the optimal design of the system is highly depended on the control system. In Thermally Activated Building Systems (TABS), which are embedded pipes in the concrete of the building structure, the role of control is pivotal and thus the control has to be simulated during the design. Therefore, the building model and optimal control has to be coupled to an optimisation algorithm for optimal component sizing. This results in a computationally heavy design procedure. This paper addresses the need for a for a simplified methodology for modelling building with TABS. The dynamic heating and cooling loads of the building is calculated by a white-box detailed Modelica model and later used in an equivalent simplified resistorcapacitor (RC) model. The simplified model was developed by the grey-box approach and the parameters of RC model were estimated by inverse modelling approach. The methodology was applied on three different case studies and the results imply that the developed methodology can be confidently coupled to an optimal control algorithm to be used for sizing HVAC components optimally. Key Innovations• An automated algorithm for simplified dynamic modelling of building with TABS • Taking the advantage of white-box modelling to have high accuracy Practical ImplicationsA simplified modelling approach is proposed to simulate TABS and building interactions. The methodology can be efficiently integrated to the optimal design methodologies due its low mathematical complexity.