Conventional thermal insulation leads to thermal decoupling of the outdoor and indoor climate. In order to limit heat transmission losses this is very useful, however, the thermal insulation is static in comparison to the dynamically changing outdoor climate. Adapting the insulation effect to the respective ambient conditions can contribute to a decrease in heating energy demands of buildings on the one hand, as well as to a reduction of overheating in summer on the other hand. In the first case, a reduced insulation of external building components is useful if there is a high outdoor temperature or high solar radiation onto the facade during the heating period. In the second case, during cool summer nights the reduced insulation leads to an emission of surplus heat from the building interior by heat transmission into the environment. In this work, various methods of switchable thermal insulation are presented and discussed. The potential capacity of switchable thermal insulation for heating as well as for a reduction of overheating in summer is investigated using simulation calculations. To this end, an idealised switchable thermal insulation was examined for which both effects could be established. The saving in heating energy is in the single digits. To evaluate the magnitude of the reduction of overheating in summer it was compared to increased night ventilation.
Schilly, T; Carrigan, S; Kornadt, O
Switchable thermal insulation - a theoretical approach
Bauphysik