In a bottom-up model for the simulation of the future energy use of households, called SAVE households, a large number of saving options were analysed in conjunction with the growth of the number of inhabitants, dwellings, households and other structural changes which influence energy use before savings, The calculated change in energy use from the base year level was presented in the form of so-called volume, structure and saving effects, This model was adapted to serve as a monitoring tool, In 1996, it was used for the first time, for the official annual monitoring exercise of environmental trends in the Netherlands, as a tool to analyse the changes in household energy use in the period 1990-1995. If sufficient information on a detailed level is available, the approach based on the adapted simulation model has a number of advantages over other methods, eg energy intensity analysis methods using the disaggregation of energy use, The model offers a very flexible structure with regard to the preferred definition of saving options and structural changes, Furthermore, the adapted model is capable of handling the interdependence between structural changes and saving options and the substitution between different energy carriers, In addition, very complex changes with regard to energy use, such as smaller household sizes or a higher fraction of dwellings with district heating, can be easily analysed.