ABSTRACT. In the presented paper assumption is being raised that ceteris paribus forecasted energy efficiency until the year 2050 reveals competitive potential, which could be reached if technological progress is ongoing and no radical changes in the energy consumption culture are observed. The research methodology is as follows. In order to clarify what trends of energy efficiency change are preconditioned by the structure of the economy, technological potential and behavioral patterns, activity level and energy intensity in the household sector are forecasted for the selected European countries -Poland, Lithuania and Germany. Lithuania and Poland represent here the countries slightly less economically developed as compared to highly developed Germany. Long-range energy forecasting software LEAP, developed by Stockholm Environment Institute is being employed for the long-term forecasting of energy use and energy intensities in the household sectors. The obtained results, as we have expected, allow verifying if consistent patterns of energy intensity change is existent for currently comparatively less developed and better countries, and if such patterns differ. Peculiarities of energy intensity change in less developed and more developed European countries are to be economically interpreted. The obtained results will allow to judge about change of competitiveness of the considered countries. Provided insights can be instrumental for devising national economic policies oriented on more efficient energy use in the long run.JEL Classification: N70, O18