WASHINGTON, DC, April 22, 2021 — At the Leaders Summit on Climate hosted by President Biden, the U.S. government pledged to help countries achieve their climate ambitions through expanding access to clean cooking.
“Providing clean energy to households is critical to achieving global climate and sustainable development goals,” said Helena Molin Valdés, Head of the Climate and Clean Air Coalition Secretariat. “Smoke from fireplaces, cook stoves, and lighting is responsible for more than half of human-made black carbon emissions and millions of premature deaths from household air pollution. The Climate and Clean Air Coalition partners welcome the U.S. government’s re-engagement in the issue and look forward to cooperating to put in place solutions that improve lives and protect the planet.”The United Nations Foundation’s Clean Cooking Alliance
Would it be helpful to add climate metrics to the health-based ISO 19867? Currently, Scoring Tier 5 for emissions of PM2.5 and CO means that safety is assured in average households. As the score decreases from Tier 5 to Tier 0 the estimated amounts of ill health from breathing smoke and gas increase.
During ISO 19867 testing under an emissions hood, the fuel use, thermal efficiency and emissions of CO2, CO, and PM2.5 are measured and the data is used to determine a ranking on the voluntary tiers of performance. ARC multiplies lab data by a factor of three to estimate in field emissions. Usually in cook stoves, the CO2 has by far the largest effect on climate change. However, PM (black to white in color), CO, methane (CH4), non-methane hydrocarbons (NMHC), and nitrous oxide (N2O) also have varying amounts of climate forcing potentials. Currently, CO2, PM2.5, and CO are measured as a part of ISO 19867. ARC also determines the amount of black carbon in every test (using a filter) of PM2.5. Adding methane and non-methane hydrocarbons to the measured gases is not difficult. In fact, Sam is working on adding them to the LEMS right now.
The effects of inhaling particulate matter have been widely studied in humans and animals. They include asthma, cardiovascular disease, and premature death. Particles can also have an extremely strong effect on the atmosphere by absorbing and/or scattering the sun’s incoming radiation, depending on their color. The black particles have an approximate warming potential by weight of 680 times that of CO2 (Roden and Bond, 2006; Bond and Sun, 2005).
When we studied the global warming impact of five cook stoves burning biomass, CO2 was shown to be the major component, as seen above. At the time (2008), estimates of the various warming potentials were:
CO2….1 (IPCC, 2007)
CO….1.9 (IPCC, 2007)
CH4….25 (IPCC, 2007)
NMHC….12 (Edwards and Smith, 2002)
N2O….298 (IPCC, 2007)
PM – Black….680 (Roden and Bond, 2006; Bond and Sun, 2005)
PM – White….-50 (Estimate – Bond, 2007)
Warming potential, 100-year, CO2 equivalents
- When biomass is harvested sustainably, the CO2 emissions from biomass-burning are considered to be greenhouse-neutral.
- Although N2O is a strong climate-forcing constituent, emissions from the wood- and charcoal-burning stoves were very low, contributing less than 1% to the overall warming potentials.
- The data suggests that there are biomass stoves that can be designed to (1) reduce the fuel used to cook, (2) reduce health-damaging emissions and (3) address climate change. The considerable differences in climate-changing emissions from the stoves in this study should be noted. Large-scale use of cleaner burning stoves might well reduce global warming effects, especially when the biomass is harvested in a “carbon neutral” manner. (N. MacCarty, D. Ogle, D. Still, T. Bond, C. Roden, Energy for Sustainable Development, 2008)