This paper deals with integrating technology as well as lifestyles variables as driving forces of energy demand in a model of total private consumption for Austria. Private consumption is determined by economic variables such as income and prices. Technology is represented by variables measuring the efficiency of households' capital stocks such as electrical appliances, heating systems and passenger cars. Lifestyles are taken into account by socio-demographic variables depicting the size and construction year of dwellings and the regional population density. Data for both types of variables are available in cross-section consumer surveys and in time-series data of aggregate consumption. The cross-section surveys provide information on income and socio-demographic factors relevant for energy demand (characteristics of building and population density). The time-series data contain information on prices and incomes as well as the level of energy efficiency embodied in household appliances. The final model of consumption incorporates a consistent combination of both time-series and cross-section information into one comprehensive econometric model. This model describes demand for energy and non-energy commodities in an almost ideal demand system (AIDS) and is used in ex-post simulation exercises to isolate the impact of technological and socio-demographic variables on the demand for petrol/diesel, heating and electricity. Results show that technological and lifestyle change has a significant influence on the energy demand of households. While technological efficiency improvements have dampened energy demand growth, especially for transportation fuels, sociodemographic (lifestyle) change has increased energy demand in the past, especially for electricity. The growing stock of energy consuming appliances, the growth of income and the moderate price development have driven energy demand up. The analysis finally draws some policy conclusions on regulating energy demand by households through carbon taxes.