Indonesia's Nitrogen Oxide Emissions Surge 50%, 29 Pollution Hotspots Detected
Nitrogen oxide (NOx) emissions in Indonesia have increased by more than 50 percent since 2010, driven by the expansion of transport, industry, power generation, and mining activities. A study by the Centre for Research on Energy and Clean Air (CREA) also identified 29 NOx emission hotspots across various regions of Indonesia, ranging from urban areas to industrial centres and nickel downstreaming hubs.
The rise in emissions has the potential to increase the formation of ground-level ozone and fine particulate matter (PM2.5) that can be inhaled by the public. CREA’s mapping shows that pollution sources are not only located in major cities but have also spread to industrial and mining areas outside urban centres.
In its report ‘Mapping the invisible: a satellite reveal of Indonesia’s NOx hotspots’, CREA mapped 29 NOx hotspots using satellite remote sensing. This figure is three times higher than the nine hotspots identified in a previous global study.
CREA analyst Katherine Hasan said NOx pollution in Indonesia is a problem involving multiple sectors. In addition to transport as mobile sources, there are stationary sources such as coal- and gas-fired power plants, industrial estates, and nickel downstreaming complexes.
‘The results of this mapping show that the distribution of nitrogen oxide emissions in Indonesia extends far beyond vehicle emissions and urban activity,’ Katherine said in a statement on Thursday (13/8/2026).
The report divides the 29 hotspots into four main groups: urban areas adjacent to power plants and industry, large industrial estates in small towns, nickel processing areas, and mining.
Nine hotspots are located in densely populated cities such as Greater Jakarta, Surabaya, and Medan. These areas have high vehicle activity and are close to fossil-fuel power plants.
Another nine hotspots are located around cement and paper factories in rural coastal areas and urban fringes in Java and Sumatra. North Jakarta and the Outer Bekasi area occupy the top two positions as NOx hotspots, followed by Suralaya in Banten in third place and West Karawang-Cikampek in sixth.
These four hotspots also contribute to an airshed with chronically high pollution levels in the Greater Jakarta metropolitan area. In addition, five hotspots stem from coal mining activities in Kalimantan, while six others are concentrated in coal-based nickel downstreaming areas in Sulawesi and North Maluku.
CREA noted that captive coal-fired power plant capacity to support coal-based nickel processing has increased more than sixfold since 2019, from 3 gigawatts to 16 gigawatts. This increase has pushed NOx emissions in Sulawesi and North Maluku to exceed emissions across the entire Greater Jakarta area.
‘This mapping shows that the burden of air pollution is no longer confined to urban areas. Communities in rural areas living around industrial and mining centres now bear severe health risks, with emission levels that often match or even exceed those of Indonesia’s largest cities,’ Katherine said.
Exposure to NOx can affect the respiratory and cardiovascular systems. In the atmosphere, the gas can also react to form ground-level ozone and fine particulate matter PM2.5, which risk worsening air quality.
Professor of Environmental Health at the University of Indonesia’s Faculty of Public Health and ISER UI researcher Budi Haryanto explained that exposure to NOx and PM2.5 can affect respiratory organs and the cardiovascular system, particularly among vulnerable groups such as children and the elderly living near high-emission areas.
‘To prevent a surge in the national health cost burden and protect the productivity of future generations, the government must tighten air quality standards in line with WHO and place health impacts as the primary consideration in every energy and industrial policy,’ he stressed.
The CREA report also notes that Indonesia’s annual ambient air quality standard for NOx remains five times more lenient than the World Health Organization (WHO) guidelines. This condition leaves the public potentially exposed to pollutant concentrations deemed unsafe by global health standards.
CREA’s analysis shows that some emission hotspots remain outside the reach of official monitoring stations. This situation is considered likely to leave health risks and environmental impacts on communities around emission sources inadequately monitored.
CREA urged the government to improve data transparency and environmental accountability through a publicly accessible air quality monitoring system. Such a system could integrate satellite data, emission reports, and industrial chimney measurement results.
The data could also be used as an early warning system when pollution spikes occur. CREA also encouraged the adoption of Best Available Technologies (BAT) in the main emission-contributing sectors.
Senior Advisor and Co-Founder of Nexus3 Foundation Yuyun Ismawati said air pollution is no longer solely an urban problem. According to her, the increase in industrial activity and nickel processing means attention to air quality needs to be extended to industrial and mining areas.
‘The struggle of residents in the Jakarta Air Pollution Lawsuit teaches that real change occurs when the public cares and takes action. Today, the problem of air pollution extends to various regions of Indonesia, from industrial areas in Java to nickel processing centres such as Weda Bay,’ Yuyun said.
Yuyun believes the government and industry need to open up emissions data so that the public can know the air conditions around their homes. According to her, reducing NOx emissions requires the involvement of government, industry, and the public.
‘Clean air is a basic human right that must be guaranteed by the Government, and together we can protect it,’ Yuyun said.