A numerical comparison of different methods for optimizing heating-restart time in intermittently occupied buildings

The article starts with a brief recap of the restart time optimization methods: the classical methods, the methods based on fuzzy logic and the methods based on the use of a building model. In order to compare these different approaches, an intermittent heating controller, which makes it possible to define different methods for optimizing heating-restart time, has been developed as part of the TRNSYS software. Two of the six methods under study are new. These are the method based on fuzzy logic and the method using a two time constant building model. The numerical simulations carried out concern a building of which three rooms are studied. The changes in the various variables are presented in the case of the method based on fuzzy logic. Next, the different methods are compared according to restart precision, comfort obtained at the beginning of the occupancy period and energy consumption over the entire period of simulation. (C) 1999 Elsevier Science Ltd. All rights reserved.