A strategy to ease indoor pollution
Improving efficiency of woodburning stoves will help Africans breathe easier

By Robert Sanders, Public Affairs

11 September 2002 | At the recent World Summit on Sustainable Development in Johannesburg, a Berkeley professor joined the Environmental Protec-tion Agency in announcing a major international effort to help reduce indoor pollution from cooking fires, a major cause of respiratory illness in the developing world.

The goal is to provide simple, cheap stoves that burn more efficiently, with less smoke and fumes, thus reducing the incidence of acute and chronic respiratory infections, says Daniel Kammen, a professor in the Energy and Resources Group and in the Gold-man School of Public Policy, and director of the campus’s Renewable and Appropriate Energy Laboratory. Such respiratory infections, which commonly lead to pneumonia, are the leading cause of mortality from infectious diseases, with an estimated 3.5 to 4 million deaths worldwide each year, according to World Health Or-ganization data from 2000.

The program also will reduce greenhouse-gas emissions and ease the burden and cost of obtaining fuel, a major expense in much of the developing world.

The international partnership, supported not only by the United States and numerous developing countries but by Canada, Mexico, and Italy, was one of the major initiatives launched by the United States at the 10-day summit. In practice, the initiative will try to stimulate the production of cheap, efficient, vented stoves locally, and attempt to replace low-quality fuels with fuels that burn more efficiently, such as sustainably harvested wood and, in some cases, charcoal.

“This initiative is dirt cheap,” Kammen says. “We are talking about stoves that in the field cost a buck apiece. If you start getting 10, 20, 30 million dollars from developed countries, plus whatever AID missions and local governments do, that can be a large amount.

“You have to look at this in terms of public-health budgets in developing countries,” he continues. “In Kenya, the public-health budget for respiratory health last year was perhaps $40,000 — and they are doing a reasonable job of promoting these stoves already. Kenya is considered a success case. So several tens of millions of dollars can have a huge impact.”

For the past 10 years, Kammen has worked in Kenya, Uganda, and Central America to develop, test, and distribute stoves to poor families who otherwise could not afford them, even at $1 each. With the advice of Kammen and others, more than 1 million improved stoves have been built and sold locally in Kenya by a network of entrepreneurs in the informal sector.

To document the effectiveness of these stoves, he embarked five years ago (with colleague Majid Ezzati, now a fellow at Resources for the Future in Washington, D.C.) on a before-and-after study of nearly 80 households encompassing 400 to 500 people in central Kenya. After measuring pollution levels in each household, they offered them a free manufactured stove — a simple, ventilated clay bowl about 18 inches in diameter, sufficient to support a pot and burning either wood or charcoal. Most households had only the simplest stove — a triangle of three rocks.

After the households started using the more efficient wood-burning stoves, exposure levels dropped 40 percent. When they used charcoal, exposure dropped 90 percent compared to traditional woodburning stoves. The results indicate that this practice, if maintained, would result in a 20- to 45-percent reduction in lower respiratory infections in children alone.

Study results were published in The Lancet, Environmental Health Perspectives, and Energy Policy.

Countries including China and India have done a great deal on their own to distribute cleaner- burning stoves, but much remains to be done when more than half of all households worldwide cook or heat their homes with wood, agricultural waste, or dung.

“What is different today, compared with the Rio summit 10 years ago, is that over the last 10 years our knowledge of the public-health and energy issues involved in using clean-burning stoves has changed dramatically,” Kammen says. “Ten years ago we probably would not have known precisely how to focus the efforts of such a program, or how to utilize local markets to do this cost-effectively. Today we can do that.”