In 2022, energy efficient district heating (DH) systems, i.e. systems that meet one of the criteria defined in Article 50 of the Act on Energy Efficiency, produced almost 87% of all heat in DO systems, which is the highest value in the observed period. The total share of heat from renewable energy sources (RES) and waste heat amounted to almost 21% in 2022. It increased by 2 percentage points compared to the previous year, and by 5 percentage points compared to 2016. It was 1.5 percentage point higher than the 2022 indicative target value, set according to the Renewable energy directive. Despite the fact that a large part of the heat is produced in energy efficient DH systems, greenhouse gas (GHG) emissions from these systems are high and their reduction can only be achieved by replacing old coal units and gradually replacing fossil fuels with RES.