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Berkeley, CA & Boston, MA – A study by researchers at the University of California, Berkeley, and the Harvard School of Public Health, finds that promoting cleaner, more efficient technologies for producing charcoal in Africa can save millions of lives and have significant climate change and development benefits. The findings appear in the April 1, 2005 issue of the journal Science.
The African continent depends on wood and charcoal for cooking and heating homes. In 2000, nearly 470 million tons of wood were consumed in homes in sub-Saharan Africa in the form of firewood and charcoal, more wood per capita than any other region in the world. More than 1.6 million people, primarily women and children, die prematurely each year worldwide (400,000 in sub-Saharan Africa) from respiratory diseases caused by the pollution from such fires. The study finds that smoke from wood fires used for cooking will cause about 10 million premature deaths among women and children by 2030 in Africa and release about 7 billion tons of carbon in the form of greenhouse gases to the environment by 2050, about six percent of the total expected greenhouse gases from the continent.
The authors assessed multiple strategies to reduce mortality as well as greenhouse gas emissions from household fuel sources. They gathered a large database of current fuel use in African nations. Using this as a baseline, they defined multiple scenarios for future fuel use by varying the mix of wood, charcoal and petroleum-based fuels used in households and improving the sustainability of wood harvesting and charcoal production techniques.
Robert Bailis, graduate student at the Energy and Resources Group at UC Berkeley and the lead author of the paper said, "If the rapid urbanization continues – and all signs indicate that it will – then the trend is going to be toward greater charcoal use in Africa. It's the most affordable source of household energy. But whichever path Africa takes, we are saying there are multiple consequences, including preventable deaths and pollution emissions. Decisions made now or in the near future are going to have large effects on health and environmental outcomes in the distant future."
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The results of the study show that the best situation in Africa would be to transition from biomass fuels to petroleum-based fossil fuels such as kerosene and liquid propane gas, which can prevent between 1.3 and 3.7 million premature deaths, depending on the speed of transition. They argue, however, that current economic conditions and energy infrastructure in Africa make petroleum-based fossil fuels an unlikely option. "If you switch everyone off the dirtiest fuels to burning clean fossil fuels, you get the biggest health benefit," acknowledged Daniel Kammen, the Class of 1935 Distinguished Chair of Energy at UC Berkeley and a co-author of the paper. He continued, "But the economic cost to most African nations – collectively the poorest region of the globe – of that switch is impossible."
Charcoal burns cleaner and produces less indoor pollution than wood, but the current inefficient production method in Africa is one of the most polluting for the global environment and potentially destructive to African forests. Their analysis shows that charcoal can provide comparable health benefits of between 1 and 2.8 million avoided deaths. Majid Ezzati, Assistant Professor of International Health at the Harvard School of Public Health and a co-author of the paper added "It's a lot easier to disseminate charcoal in large scale than fossil fuels, because there is a well developed market and you don't need expensive infrastructure like refineries and processing. So, even though fossil fuels are in fact better for health and better for climate, they are more expensive and a lot harder to get out."
However, scenarios that envision large shifts to charcoal without improvements in harvesting and production lead to severe increases in greenhouse gas emissions, with over 15 billion tons of carbon released into the atmosphere by 2050. "Most charcoal is produced in Africa by one or two guys going out in the woods, almost always without a permit and on somebody else's land, cutting down a tree or two, chopping it up, lighting it, covering it with dirt, and then hovering around it for 2-4 days while it becomes charcoal," Kammen said. "It's no surprise it's not generally a high-efficiency operation." The authors found that by creating the technological and policy tools for transitioning to higher efficiency charcoal production technologies and sustainable harvesting, like those used today in Brazil and Thailand, greenhouse gas emissions can be reduced by 45-66 percent.
The researchers conclude that helping African nations make the transition to clean charcoal without drastically increasing pollution and decimating tropical forests would be an excellent way to achieve several of the United Nation's "millennium development goals," among them reducing child mortality, and ensuring gender equity and environmental sustainability, and to invest in development of the African continent as promised at the 2005 World Economic Forum and the recent G-8 summit. Ezzati said, "This study shows that choosing energy technologies with an eye toward improving health and quality of life in one of the world's most impoverished areas offers us opportunity to significantly reduce premature deaths, especially among women and children."
The research was supported by the United States Environmental Protection Agency Office of Atmospheric Programs, the Energy Foundation, the University of California Class of 1935 Chair, and the National Institute on Aging.
Harvard School of Public Health is dedicated to advancing the public's health through learning, discovery, and communication. More than 300 faculty members are engaged in teaching and training the 800-plus student body in a broad spectrum of disciplines crucial to the health and well being of individuals and populations around the world. Programs and projects range from the molecular biology of AIDS vaccines to the epidemiology of cancer; from risk analysis to violence prevention; from maternal and children's health to quality of care measurement; from health care management to international health and human rights. For more information on the school visit: www.hsph.harvard.edu
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