In the paper the solutions how to decrease the energy consumption for the most common types of buildings in urban areas of The Republic of Moldova using the modern practice of improving energy efficiency are shown. Here we mean modernization measures like thermal insulation and integration of renewable energy sources. A study has been made for the schedule of energy consumption and the losses of energy inside the buildings. Were described the technical possibilities of mounting of such sources as, solar collectors, photovoltaic panels, devices for recovery the waste heat. The optimal operating conditions of renewable and traditional energy sources with subsequent analysis of the effect gained from measures described are submitted.