Research in Chile, Colombia, and Brazil reveals the impact of residential cooking emissions and proposes alternatives to drive the energy transition and improve quality of life.

The recent study on the energy transition in the residential sector, carried out in Chile, Colombia, and Brazil, has revealed findings that call for action. This study highlights existing challenges in these countries, such as leaks from cooktops even when switched off, and levels of indoor pollution that exceed international air quality standards.

Methane (CH₄) has become a crucial focus in the fight against climate change due to its high global warming potential—28 times greater than that of carbon dioxide (CO₂). Although its atmospheric lifetime is relatively short, its impact on warming is significant. According to the latest IPCC report (AR6, 2023), increases in methane concentration account for an estimated 35% of the anthropogenic greenhouse gas (GHG)–driven warming, making it the second-largest driver of human-caused climate change after CO₂. This makes methane a short-lived climate pollutant with immediate impact. Reducing methane emissions is critical to limiting near-term warming because, if swiftly reduced, atmospheric concentrations would decline over decades rather than centuries—key to meeting the Paris Agreement goal of limiting global temperature rise.

Indoor pollution, especially linked to the use of natural gas stoves and cookers, poses a significant health risk due to emissions of methane (CH₄) and other pollutants that degrade air quality. Studies indicate that people spend up to 90% of their lives indoors—about 60% of that time at home (Vardoulakis et al., 2019)—amplifying exposure to these hazards. At elevated concentrations, methane can displace oxygen in enclosed spaces, causing symptoms such as asphyxia, nausea, vomiting, and vision problems. The presence of other compounds—carbon dioxide (CO₂), carbon monoxide (CO), nitrogen dioxide (NO₂), and benzene (C₆H₆)—further aggravates risks, from eye irritation, headaches, and dizziness to severe respiratory complications. These effects underscore the importance of mitigating indoor pollution sources to protect health.

In Chile, the residential sector is responsible for 22% of national CO₂e emissions. Measurements carried out in Santiago and Temuco indicate that emissions from the use of natural gas cookers in homes account for: 7% of residential carbon dioxide emissions, 1.56% of total residential fugitive and non-fugitive methane emissions, and 0.77% of carbon emissions in the residential sector.

In Colombia, the residential sector accounts for 19% of energy consumption. The measurements reveal that: natural gas cooking devices emit even when switched off; methane emissions during burner ignition and shutdown are significant; and methane emission rates in the residential sector may be substantially underestimated in national inventories, since the emission factor obtained in this analysis is considerably higher than the reference values used by the IPCC and by UPME in the country.

In Brazil, the 2020 summary of the National Energy Balance highlights diverse energy sources used in households nationwide, with electricity predominant at 46% of total household installations. However, reliance on other fuels—firewood (26.6%), liquefied petroleum gas (LPG) (24.4%), and natural gas (NG) (1.5%)—varies significantly by region (EPE, 2020). This picture is complemented by data showing substantial variability in emission concentrations, seemingly related to the type, quality, age, and maintenance of stoves studied. Although exact causes of the variations cannot yet be determined, research continues into factors such as gas type, stove age, stove/cooktop type, and dwelling type (apartment or house).

Furthermore, nitrogen oxides (NOx) concentrations—especially nitrogen dioxide (NO₂)—remain close to the World Health Organization (WHO) guideline, fluctuating around 106 ppb, slightly above the 100 ppb recommendation. Overall, values are below the health-effect limit (NIOSH 2,000 ppm), except in a few cases in cycle 2. Although in the constant shutdown event (St_OFF) NO₂ values sometimes exceed the WHO guideline (106 ppb for 1 hour), note that this limit applies to outdoor ambient conditions, not indoors. Even where values are higher, they remain below the health-effect limit (1 ppm, per NIOSH REL ST) under standard operating conditions. NO concentrations remain below the health-effect limit (25 ppm, per NIOSH REL TWA) under standard operating conditions.

The study also reveals that the methane emission factor obtained from measurements using natural gas (NG) is significantly higher than estimates at both national level and by the IPCC. With an average of 14.58 g/TJ excluding outliers and 48.92 g/TJ including all data, the emission factor found is 49 times higher than the national value and 9.8 times higher than the IPCC value. All these data underscore the importance of continuing to monitor these emissions, especially indoors, where pollutant concentrations can have more direct health effects. This highlights the need to review national policies and emission estimates and to implement stricter measures to reduce methane—a potent greenhouse gas.

All three countries have policies aiming for a just residential energy transition. However, the data presented stress the importance of concrete measures to ensure effective implementation.

Today, Chile is driving the energy transition toward 100% zero-emission power by 2050 with specific policies and programmes such as the Energy Policy 2050, the 2020 Residential Energy Transition Strategy, and the Electricity Subsidy Bill.

Colombia proposes accelerating the residential energy transition with a robust National Strategy and a stronger push for electrification; regulation for micro-grids and distributed generation; a carbon tax applicable to gas; and an information system to promote efficient appliances.

Brazil is advancing the energy transition and climate mitigation through key policies and programmes, including the National Climate Change Policy; energy efficiency and “fuels of the future” laws; the “My House, My Life” programme for rooftop PV; and the National Zero Methane Programme promoting biogas use.

There are opportunities to adopt instruments that support a just residential energy transition. Colombia proposes a programme to swap wood-burning stoves for electric resistance cookers which, in emissions terms, would avoid 11,810 tonnes of CO₂e associated with CO₂ and 428 tonnes of CO₂e associated with CH₄—achieving a 48.7% reduction relative to the LPG stove baseline.

Chile, for its part, proposes replacing pellet heaters with air conditioners, which would mean savings of over USD 3 million; health benefits valued at more than USD 20 million; and avoidance of approximately 367 tonnes of PM₂.₅ and 286 kton of CO₂e.

Assessing cooking technologies: natural gas stoves, with 42.1% efficiency, generate 0.215 kg of CO₂e per unit of useful energy, whereas induction stoves, with 79.7% efficiency, produce only 0.145 kg of CO₂e—achieving a 32.6% emission reduction with nearly double the effectiveness, considering current electricity emission factors.

The shift to electric technologies in homes emerges as a promising alternative to improve people’s quality of life. These solutions reduce dependence on fossil fuels while improving indoor air quality, directly benefiting family health. Their high energy efficiency optimizes resource use. Moreover, by generating fewer greenhouse gas emissions, these technologies play a key role in combating climate change. Adopting them is a step toward a cleaner, healthier, more sustainable future—with tangible benefits for people and the environment.

Based on the research findings, natural gas cookers—while not the primary source—contribute significantly to emissions of carbon dioxide, methane, and nitrogen oxides in the residential sectors of Chile, Colombia, and Brazil, with a particularly high impact from methane. Emission factors used in national greenhouse gas inventories in these countries appear to underestimate actual contributions, especially for methane and nitrogen oxides.

Additionally, high NOx concentrations in poorly ventilated homes and during prolonged gas cooking pose risks to residents’ health, underlining the urgent need to improve kitchen ventilation. Experts recommend keeping windows open or using exhaust hoods while cooking, as well as opting for electric cooking and heating devices—cleaner, more efficient alternatives to protect health and indoor air quality.

Chile, Colombia, and Brazil already have efforts in place such as energy efficiency laws and transition strategies—but they are not enough. The study urges intensifying action, including implementing carbon taxes in the residential sector, public awareness campaigns, phasing out fossil fuel subsidies, incorporating the health and air-quality externality costs of firewood and fossil fuels, and including residential consumption within carbon tax schemes, among other measures.

The study provides relevant data for the scientific community and offers a roadmap for decision-makers and the public sector, highlighting specific public policy instruments by country. It also shows how immediate actions can positively influence the health, well-being, and environmental future of millions of people in Latin America. All data and analyses are available in the project’s repository.

About the project

The project “RESIDENTIAL-LEVEL ENERGY TRANSITION: Electrification of stoves and cooktops in Latin America” is an initiative led by the Global Methane Hub. It has been implemented in Chile, Colombia, and Brazil since March 2024 by a consortium made up of the Latin American Future Foundation (FFLA), EBP Chile, EBP Brazil, Stanford University, University of São Paulo, Universidad Mayor (Chile), and Universidad de los Andes (Colombia).

To learn more about this research and progress updates, visit our website: https://proyectogmh.ffla.net/

Toward a sustainable energy transition!

References

Intergovernmental Panel on Climate Change. (2023). Sixth Assessment Report. Retrieved from https://www.ipcc.ch/report/ar6/syr/

Vardoulakis, S., Giagloglou, E., Steinle, S., Davis, A., Sleeuwenhoek, A., Galea, K. S., Dixon, K., & Crawford, J. O. (2020). Indoor exposure to selected air pollutants in the home environment: A systematic review. International Journal of Environmental Research and Public Health, 17(23), 8972. https://doi.org/10.3390/ijerph17238972