Acoustic fan could ease indoor air pollution
March - April, 2009 | Volume 8, Issue 2
Photo courtesy NIEHS
Cookstoves like this one used
by a Guatemalan woman can
be made less polluting by use
of a fan.
Scientists are devising new models for the elemental stove used by half the world's population for cooking or heating but which is a large contributor to indoor air pollution (IAP) and disease estimated to take 1.6 million lives a year.
When people use the cookstoves, they usually are burning biomass - dung, wood, soft coal or rice husks - all of which produce toxic carbon emissions, increasing the risks of low birth weight, asthma and cardiovascular disease, among others.
"People will burn whatever is readily available," said William Behn, of the State Department's East Asia bureau at a meeting of NIH staff concerned with international health.
It is a known problem at the individual level, but recently the amount of soot crossing national borders and pollution by new technology makes necessary the development of alternate heating sources, Behn said.
Behn and State Department science fellows Steve Garrett and Phil Hopke said that adding a fan to the stoves would reduce emissions and cooking time.
Garrett demonstrated a small thermoacoustic engine that would turn heat from the stove into energy to run a fan by using rapidly vibrating sound waves generated by an inert gas in the device.
"It is robust, inexpensive and low maintenance," said Garrett, noting that to make a difference there might need to be as many as one billion units that are easy to use, efficient, able to be mass produced and distributed.
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