Climate & Environment
The Problem
Cooking over open fires or inefficient stoves typically entails burning fuels (such as wood, charcoal, coal, and kerosene) that release harmful, climate-warming emissions. These emissions of short-lived climate pollutants—such black carbon and methane (CH4), as well as other greenhouse gases, such as carbon monoxide (CO) and carbon dioxide—occur because of the incomplete combustion of kerosene and solid fuels during this form of cooking.
Black carbon, commonly known as soot, refers to tiny carbon particles that form during this incomplete combustion, and is by far the most significant short-lived climate pollutant emitted during cooking. Black carbon particles absorb sunlight, thereby warming the atmosphere, and are estimated to be second only to CO2 in their warming impact on the climate.1 Black carbon remains in the atmosphere only for a short period of time, then it falls back to Earth with precipitation, where it darkens the surface of snow and ice and reduces the reflecting power of these surfaces, which causes the melting of sea ice and glaciers. Globally, emissions from household energy contribute to over 50% of global black carbon emissions. In many Asian and African countries, household cooking can account for as much as 60%-80% of black carbon emissions.2
With nearly 2.4 billion people relying on firewood and charcoal (woodfuel) for cooking, woodfuel is by far the most commonly used solid fuel.3 The CO2 emissions from cooking with wood and charcoal are caused by unsustainably harvested woodfuel (harvested at a rate that exceeds regrowth). which leads to forest degradation that reduces the ability of trees and shrubs to absorb emitted carbon from the air (carbon sequestration). Around 30% of the woodfuel harvested globally is unsustainable, resulting in climate-damaging emissions equivalent to 2% of global emissions.4 Forest degradation also causes losses in erosion control, biodiversity, and flood protection.
Clean Cooking Solutions
Many of today’s more modern stoves are highly efficient and can reduce fuel use by 30%-60%, resulting in fewer emissions of greenhouse gas and black carbon.5 Recent evidence also demonstrates that the most advanced (efficient and low-emission) cookstoves and fuels can reduce black carbon emissions by 50%-90%.6 Well-managed woodlots produce sustainable woodfuel, reducing CO2 emissions. The Intergovernmental Panel on Climate Change (2018) acknowledges that reducing black carbon, methane, and other short-lived climate pollutants would not only have substantial co-benefits on health and air pollution, but can in the short-term, contribute significantly to limiting global warming to 2 degrees celsius, a long-term international goal for avoiding the most dangerous impacts of climate change.
Mitigating climate change and environmental degradation requires an inclusive industry that makes clean cooking accessible to the three billion people who live without it.
Sources:
1 Ramanathan and Carmichael 2008
2 Bond et al. 2013
3 FAO 2017
4 Bailis et al. 2015
5 Garland et al. 2017
6 Garland et al. 2017