The main target of the National Energy Strategy is the curtailment of energy consumption and thus the easing of energy dependency. In the last few years residential and tertiary sector primary energy consumption displayed a considerable drop, which may be understood as the beginning of a favourable development. Whether this decrease can be explained by energy efficiency developments and the increase of energy efficient new buildings or simply the economic crisis? May other factors be the reason? How does the energy use of residential and tertiary sector develop in the next decades? We seek the answers to these questions in our analysis.