This indicator shows the trend in greenhouse gas emissions in Slovenia and the main sources of emissions. Emissions are expressed in Gg CO₂ equivalent which takes into the contributions of individual gases according to their account global-warming potential.

Greenhouse gas emissions monitored within the emission inventory include carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), F-gasses (such as hydrofluorocarbons (HFC), perfluorocarbons (PFC) and sulphur hexafluoride (SF₆). Greenhouse gas emissions are calculated in accordance with the IPCC methodology, which enables international comparability of data. Emissions are being calculated for transport, energy, industrial processes and the use of products, fuels in industry, fuels in households and commercial use, agriculture and waste. Land use, land use change and forestry (LULUCF) represents a special category.

In 2023, Slovenia’s total greenhouse gas (GHG) emissions excluding Land Use, Land-Use Change and Forestry (LULUCF) amounted to 14,804 kt CO₂ eq, which is 21.4% below the 1990 baseline and 4.8% lower than in 2022. Including LULUCF, net emissions were 10,513 kt CO₂ eq in 2023. Slovenia’s target is to achieve climate neutrality by 2050, meaning that emissions will be balanced by sinks—i.e., net emissions (including LULUCF) will be zero.

Among all GHGs, carbon dioxide (CO₂) had the largest share in Slovenia in 2023, accounting for 81.1% of total emissions, primarily from fuel combustion and industrial processes. This was followed by methane (CH₄) with 12.4%, mostly arising from agriculture and waste management, and nitrous oxide (N₂O) with 4.3%, also mainly from agriculture. Although quantitatively small, fluorinated gases (F gases)—including HFCs, PFCs, and SF₆—due to the high global-warming potential.

The burning of fossil fuels causes the most emissions, especially in the energy sector (electricity and heat production) and transport (primarily road transport), which together contribute nearly 60% of national emissions.

In the past, the energy sector was the largest emitter, but emissions started to decline after 2014 due to the shutdown of the Trbovlje thermal power plant, the launch of Unit 6 at the Šoštanj Thermal Power Station (TEŠ), and increased biomass use. As a result, energy-related emissions in 2023 were 48.1% lower than in 1990.

Emissions from transport (99% of which are road transport) rose by 200% from 1986 to 2008. They dropped sharply in 2009 due to the economic crisis, later partially recovered, but never surpassed the 2008 peak. During the COVID-19 pandemic in 2020, transport emissions dropped by 18.7%, but have since rebounded. In 2023, they were 96% higher than in 1990 and 21.9% higher than in 2005, the baseline year for non ETS sectors.

Fuel use in manufacturing industries and construction decreased significantly: in 2023 emissions were 51% below 1990 levels. The shift from solid fuels to natural gas, along with large disruptions like the financial crisis and the pandemic, were key factors.

In fuel used in other sectors, primarily buildings, emissions fluctuate with winter temperatures and the use of biomass. Despite annual swings, the longer-term trend is a clear decline: emissions in 2023 were 33.9% lower than in 1990 and 53.6% lower than in 2005. Contributing factors include milder winters, better insulation, and increased use of wood and heat pumps.

Fugitive fuel emissions accounted for only 2% of total emissions and were down 40.4% from 1990 and 41.3% from 2005.

Industrial processes and product use saw reductions after 2008 due to slowed production during the financial crisis. However, emissions have plateaued recently, driven up by F gases from refrigeration, air conditioning, and heat pumps. In 2023, this sector’s emissions comprised 63.7% CO₂, 29.5% HFCs, 5.1% N₂O, 1.7% SF₆, and 0.1% PFCs. Cement production alone accounted for 43.1% of emissions in this sector in 2023. These emissions were 26.5% lower than in 1990 and 27.9% lower than in 2005.

In agriculture, 2023 emissions reached 1,632 kt CO₂ eq, or 11.0% of total emissions. Agriculture is the main source of CH₄ and N₂O, contributing 63.4% of methane emissions and 66.6% of N₂O emissions nationally. Within the sector, CH₄ makes up 71.6% of emissions, N₂O 25.9%, and CO₂ just 2.5%. Compared to 1990, emissions in agriculture dropped 17.7% by 2023, and by 7.4% compared to 2005. The decline is attributed to fewer pigs, improved manure management, increased dairy farming intensity, and better nitrogen fertilizer control. Enteric fermentation contributes 59.8%, agricultural soils 22.4%, manure-related methane and N₂O 15.2%, and lime and urea-related CO₂ 2.5%.

Waste sector emissions are the second-largest source of methane (17.4% of national CH₄ emissions). In this sector, methane comprises 85.2% of GHGs, N₂O 10.4%, and CO₂ 4.5%. In 2023, waste emissions stemmed from solid waste (45.7%), wastewater (45.1%), composting (4.7%), and incineration (4.5%). Total waste emissions in 2023 were 51.0% lower than in 1990 and 54.5% lower than in 2005. Since 2005, emissions from solid waste disposal sites dropped by 68.4%, due to the reduction of deposited biodegradable waste and better landfill gas capture. Wastewater emissions were 51.4% lower than in 1990, due to improved biogas capture and reduced industrial activity.

Forests covered over 58% of Slovenia in 2023 and are a significant GHG sink. Total net LULUCF sinks were –4,291 kt CO₂ eq, which is 1.6% less than in 1990. Peak sinks occurred in 2007. Afterward, natural disasters and increased sanitary logging (50% more between 2014 and 2018) turned the LULUCF sector into a net source. In the past five years, conditions improved. In 2023, removals were again higher than the reference value of –3,270 kt CO₂ eq (valid for 2021–2025). After 2026, this reference will no longer apply, and the sector’s full contribution will be accounted for.

To achieve EU GHG targets, differentiation between ETS and non ETS emissions is crucial. ETS covers major electricity and heat producers and energy-intensive industry, whose emissions decline due to annual reductions in available allowances. In 2023, Slovenia’s ETS emissions fell by 5.7% compared to 2022.

Slovenia has a national target for non ETS emissions, which are influenced by domestic policies. These emissions must not exceed levels set in Commission Implementing Decision 2023/1319. For 2023, the cap was 10,814 kt CO₂ eq. Slovenia’s actual non ETS emissions (excluding LULUCF and domestic aviation) amounted to 10,221 kt CO₂ eq, which is 5.5% below the cap. Including LULUCF, total emissions were 11.5% below the cap.

For more detailed data on non-ETS emissions see indicator PO01 in the “Climate Mirror”.

Climate policy

Back in 1992, when few were aware of the impact of GHG emissions on the climate, the United Nations Framework Convention on Climate Change (UNFCCC) was adopted in Rio de Janeiro and ratified by Slovenia in 1995. One of its key commitments is regular reporting on emission levels, measures for their reduction, monitoring of climate change, and actions to mitigate its effects. In July 2002, Slovenia also ratified the Kyoto Protocol, committing to an 8% reduction in GHG emissions during the first commitment period (2008–2012), compared to the base year 1986. Slovenia exceeded this target by 3%, primarily by using the maximum allowable carbon sinks.

During the period 2013–2020, there was no global agreement in place. However, the EU, some other European countries, and Australia agreed to jointly achieve a 20% reduction in emissions compared to 1990 levels. Slovenia met its target within this EU framework.

A major milestone in climate action came in 2015, when the United Nations Climate Change Conference in Paris adopted the Paris Agreement—the first universal and legally binding global climate accord. Its key goal is to limit global temperature rise to well below 2°C above pre-industrial levels by reducing GHG emissions and reliance on fossil fuels. Each signatory country submitted its own nationally determined contributions (NDCs), reflecting national circumstances and plans for achieving the common goal.

The EU aims to reduce net GHG emissions by 55% by 2030 compared to 1990. As of 2022, emissions had already been reduced by 32%. Net emissions include emissions from international aviation and the land use, land-use change, and forestry (LULUCF) sector.

The EU’s initial 2030 goal was to reduce GHG emissions from sectors not included in the Emissions Trading System (ETS) by 30% compared to 2005. This reduction is to be achieved through burden-sharing among Member States, with national targets primarily based on each country’s level of economic development.

Slovenia's GDP per capita is slightly below the EU average, which is reflected in its comparatively lower target. Initially, Slovenia committed to a 15% reduction in non-ETS emissions by 2030 compared to 2005, and to achieving climate neutrality by 2050. The main document outlining the 2030 target was Slovenia’s National Energy and Climate Plan (NECP), adopted by the Government in February 2020. In this document, Slovenia set itself a more ambitious national target—at least a 20% reduction in non-ETS emissions and an indicative target of a 36% reduction in total GHG emissions by 2030, compared to 2005. Climate neutrality by mid-century is addressed in the Long-Term Climate Strategy (LTS or ReDPS50).

In early July 2021, the European Commission adopted the European Climate Law, which further tightened the 2030 GHG reduction target to at least 55% compared to 1990. To support implementation, the Commission introduced the "Fit for 55" legislative package, which amends existing legislation to align with the updated targets. This includes revisions in GHG reduction for both ETS and non-ETS sectors, as well as measures for improving energy efficiency and increasing the use of renewable energy sources.

Following the EU's revised goal, Slovenia’s target was also tightened—to reduce non-ETS emissions by at least 27% by 2030 compared to 2005. In line with this target, the Slovenian Government adopted a revised National Energy and Climate Plan at the end of December 2024 and submitted it to the European Commission.