Energy saving potential of occupancy-based heating control in residential buildings

A significant amount of energy is wasted every year by heating unoccupied indoor spaces in residential buildings. How much energy can be saved by reducing the heating during the hours with no occupancy? Simulation results of a multi-family residential building typical for the Swiss housing stock show that, when the setpoint temperature is equally reduced in all apartments during the hours with no occupancy, energy savings in the order of 6-9% for the whole building and 3-13% for the individual apartments can be achieved.