Exploring the potential of climate adaptive building shells

Roel C.G.M. Loonen, Marija Trcka, and Jan L.M. Hensen (Eindhoven University of Technology)

Building shells with adaptive, rather than static properties, intuitively offer opportunities for both energy savings and comfort enhancements. Progress in this field is characterized by fragmented developments, and the most effective type of climate adaptive building shell (CABS) behaviour is still unknown. Therefore, also the true value of CABS is not yet determined. This paper explores and quantifies the latent potential of CABS by using building performance simulation in combination with multi-objective optimization and advanced control strategies. Climate adaptive building shells offer the ability of actively moderating the exchange of energy across a building’’s enclosure over time. By doing this in a sensible way, in response to prevailing meteorological conditions and comfort needs, it introduces good energy saving opportunities. The work presented explores the potential of CABS firstly by applying a multi-objective optimization in order to find the best performing static building shell designs. In the second and third step, the paper investigates the possibility for performance improvement with CABS at two characteristic timescales: short-term and long-term. Generation of the most optimal building shell design is done by embedding TRNSYS simulations in modeFRONTIER. The  authors selected the non-dominated sorting genetic algorithm II (NSGA-II) with the following performance indicators, and also objectives to be minimized:

Results show that the best performing static building shell needs to make compromises in order to satisfy performance requirements throughout the whole year. This signals clear opportunities for the use of CABS. In the case of short term adaptation CABS, when the simulation was run for the whole year, it turned out that an energy saving potential of 60 per cent is feasible compared to a reference zone with fixed building shell properties. From this potential, 80 per cent is attributable to a reduction in cooling energy demand.