Center for the Built Environment

While Thermally Activated Building Systems (TABS) is a recognized low-energy HVAC candidate system for net-zero-energy buildings, sizing of these systems is complex due to their slow thermal response. In this paper, seven design and control models have been reviewed and characterized systematically with an aim to investigate their applicability in various design scenarios and at different design stages. The design scenarios include variable space heat gain, different building thermal mass and varying pump operating hours. Three design stages were considered, including feasibility study, early design decisions and detailed sizing. The applicability to different design stages was evaluated based on a compromise between accuracy and ease of implementation of the design methods. Five of the models were shortlisted for a future simulation-based evaluation and recommendation.