In 2023, 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 87,7% 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 21,2% in 2023. It increased by 0.5 percentage points compared to the previous year, and by 5.5 percentage points compared to 2016.

According to the data for 2023, GHG emissions per unit of electricity produced amounted to 166 gCO₂/kWh. In the period 1992–2023, the intensity of GHG emissions decreased by 62,4%. Compared to the EU-27 average, intensity of GHG emissions in Slovenia in 2023 was 19,8% lower.

In 2023, 65% of the population was connected to municipal wastewater treatment systems with secondary or tertiary treatment, which do not produce GHG emissions. Compared to the previous year, the share increased slightly, and compared to 2017, it rose by 3.5 percentage points.

In 2023, the share of RES in transport, after a significant drop in 2022, increased again and amounted to 10%. With this, it was 0.7 percentage points behind the non-binding 2023 target from the National Energy and Climate Plan (NECP).

Slovenia’s import dependence has been lower in recent years, amounting to 48% in 2023. Further increases in energy efficiency, the use of renewable sources, and the diversification of supply sources are essential. Slovenia is completely import-dependent for liquid fuels and natural gas. With regard to natural gas, Slovenia is import-dependent on two countries, Austria and Algeria. In the past, gas reaching Austria mostly came from Russia, but in recent years the supply structure has become more diversified due to the war and sanctions.