Should we design buildings that are less sensitive to occupant behaviour? A simulation study of effects of behaviour and design on office energy consumption

In an ideal world, occupants have an understanding of how building systems work and are motivated to use the systems as they were designed to be. There is considerable evidence, however, that occupants do not understand the principles of how buildings function and that they use the systems non-optimally. The purpose of the paper is to quantify the effect of occupant behaviour on energy consumption and show how it is affected by design strategies. Numerical simulations of an office were performed with the dynamic thermal simulation software TRNSYS. Three types of behaviour ('careless', 'normal', and 'conscious') and two types of design ('ordinary' and 'robust') were considered. The results show that the effect of occupant behaviour on energy consumption is greatly diminished with robust design solutions, solutions that make buildings less sensitive to occupant behaviour. The careless user consumes 75-79 % less energy if the robust design solutions are applied rather than the ordinary design solutions. It is argued that a realistic view of occupant behaviour is advantageous in the creation of energy-efficient buildings (that is, leaving less need to learn how buildings work, to be motivated to save energy, or to perform specific energy-saving actions). However, the possibility of personal control should not be eliminated.