Perhaps as many as 400 million of these stoves, fueled by wood or crop residue, are used daily for cooking and heating by more than 2 billion people worldwide, according to the study's lead authors, Tami Bond, Ph.D., and doctoral candidate Chris Roden of the University of Illinois, Urbana-Champaign. In a field test in Honduras, the researchers found that cook stoves there, which are similar to those used in other developing nations, produce two times more smoke particles than expected, based on previous laboratory studies. These dark, sooty particles, which are darker than those produced by grassland or forest fires, have a climate warming effect because they absorb solar energy and heat the atmosphere, according to Roden.
In earlier work, Bond estimated that burning firewood -- the principal fuel for cook stoves in the developing world -- produces 800,000 metric tons of soot worldwide each year. In comparison, diesel cars and trucks generate about 890,000 metric tons of soot annually. These two sources each account for about 10 percent of the soot emitted into the world's atmosphere each year, she said.
In addition to its environmental effects, smoke from cook stove fires is a major cause of respiratory problems, eye infections and tuberculosis, according to the researchers.
"Emissions from wood cook stoves affect the health of users -- especially of women and children -- neighborhood air quality, and global climate. Reducing these emissions, through the use of cleaner burning stoves and fuels, should have far-reaching benefits," Bond said.
In the past, scientists have relied on laboratory measures of pollutants from cooking fires because field tests have been difficult to conduct, in part, because of limited access to remote locations and a lack of power to operate the scientific equipment, according to Roden. To get a more accurate measure of the environmental impact of these stoves, Roden and Bond developed a portable battery-operated sampling cart, which includes sensors for measuring carbon dioxide and carbon monoxide, particle soot absorption, particle color and concentration, which they took to Honduras for field tests.
Honduras is typical of Central American countries, where more than 80 percent of families cook their meals over open wood fires, according to Trees, Water & People, an American nonprofit agency which, along with the Honduran Association for Development, helped facilitate this study. In most cases, these families can't afford or don't have access to electricity, gas or alternative fuel sources.
"We expected field measurements to be different from lab measurements, and we suspected the amount of black carbon from these stoves would be higher than open burning, but we were surprised by how much," Roden said.
Trees, Water & People and other nonprofit agencies are distributing new low-cost, wood-burning cook stoves in Honduras and other Latin American countries that appear to be less polluting and more fuel efficient, according to the researchers. However, further analysis is needed.
"Designing and distributing improved cook stoves may be an effective method of mitigating global climate change, and can improve the health of the users," Roden said. "However, the cook stoves must be well designed and properly tested. They must be built with local traditions and practices in mind and must be easy to use, or they may become expensive doorstops."
Michael Bernstein | EurekAlert!
Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel
Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
19.02.2018 | Information Technology
19.02.2018 | Ecology, The Environment and Conservation
19.02.2018 | Life Sciences