Global energy-related emissions were unchanged at 33.3 gigatonnes (Gt) in 2019 after two years of growth, according to the International Energy Agency (IEA).
This was largely due to power sector emissions dropping by 170 million tonnes (Mt), or 1.2% from 2018 levels.
Milder weather in several countries and slower economic growth in some emerging markets also contributed.
The IEA said the expanding role of renewables — mainly wind and solar PV — was a key reason for the decline in power sector emissions, alongside the move from coal to gas and higher nuclear power generation.
However, preventing further growth in global emissions was only achieved by significant decreases in developed countries offsetting continued growth elsewhere, the IEA noted.
Its director general Fatih Birol said the figures were proof that ambitious policies and investments could help to limit emissions.
“This welcome halt in emission growth is grounds for optimism that we can tackle the climate challenge this decade,” he added.
“It is evidence that clean energy transitions are underway.”
Energy-related CO2 emissions in advanced economies fell by 3.41% to 11.3Gt and increased by 1.85% to 22Gt in the rest of the world, according to IEA data.
Wind accounted for the biggest share of the increase in renewables, with its output rising by 12% from 2018 levels, the IEA added.
“We now need to work hard to make sure that 2019 is remembered as a definitive peak in global emissions, not just another pause in growth," Birol added.
The sharpest fall in total energy-related CO2 emissions was achieved in the US — down 140 million tonnes, or 2.9%.
There, coal-fired power generation decreased by 15% due to stronger competition from natural gas, with benchmark gas prices down by 45% from 2018 on average.
Gas, therefore, increased its share in US electricity generation to a record-high 37%, while overall electricity demand declined due to a milder summer and winter, the IEA explained.
In the European Union, including the UK, energy-related emissions were down by 160 million tonnes or 5%. Coal was surpassed in generation by natural gas for the first time, while wind power nearly caught up.
Emissions in the EU’s power sector fell by 120Mt of CO2, or 12%. Output from coal-fired plants in the EU were down by more than 25%, while gas-fired output increased by nearly 15%.
In Japan, energy-related emissions were cut by 45 million tonnes or around 4%. This was the country’s fastest pace of decline since 2009, as it increased output from restarted nuclear reactors, the IEA explained.
However, in the rest of the world, energy-related emissions were up by nearly 400 million tonnes, with almost 80% of the increase coming from Asian countries where coal-fired generation continued to rise.
Coal demand continued to increase in Asia, accounting for more than half of the continent’s energy use. It was responsible for about 10Gt of emissions — just under a third of the global total in 2019.
China’s emissions rose in 2019, but this increase was limited by slower economic growth and higher output from low-carbon sources of electricity, the IEA stated.
Renewables continued to expand in China, and 2019 was also the first full year of operation for seven large-scale nuclear reactors in the country.
Meanwhile, coal-fired electricity generation in India fell for the first time since 1973 due to strong renewables growth and stable electricity demand.
Emissions from India’s power sector declined slightly, but those savings were offset by continued growth in fossil-fuel demand in other sectors of the economy, such as transport.
Emissions also grew in south-east Asia, where there was robust demand for coal.