Feasibility of the green transition and energy saving potential in buildings

The European “Green Deal” is an ambitious plan to phase out fossil and nuclear fuels in the near future, i.e. by 2050, and replace them with renewable energies (electricity, synthetic fuels, hydrogen, etc.). Despite years of efforts and extensive investment in renewable energy sources, their share of final energy is only increasing very slowly. The global share of renewable energies is less than 15 %. The development of renewable energy in Slovenia between 2003 and 2019 is analysed, where its share in primary energy has increased from ~10% to 20%, mainly due to the use of wood for energy. At the current level of consumption, a complete switch to green energy is neither technically nor economically feasible with the currently mature technologies. It is therefore necessary to look for solutions that also enable a reduction in energy consumption. One of these solutions for the building sector is passive house technology. The passive house is characterised by an extremely low heating energy consumption of a maximum of 15 kWh/m 2 per year. A practical example of energy use in a passive house is discussed. It is shown that the energy consumption in a passive house is only one third of the statistical average consumption.