A 2006 report from the World Health Organization (WHO) called Fuel for Life: Household Energy and Health, estimated that levels of particulate matter with diameter below 10 micrometers ("PM10") in homes that use solid fuels for cooking can reach 300-3,000 micrograms per cubic meter (averaged over a 24-hour period), with peaks approaching 10,000 micrograms per cubic meter during cooking. WHO recommends a maximum 24-hour average of only 50 micrograms per cubic meter. For comparison, in 2008, the highest 24-hour average for PM10 in the South Coast air basin was 126 micrograms per cubic meter (via the California Air Resources Board's air quality data website). Adler reports on a large study in Guatemala (led by UC Berkeley Professor Kirk Smith), where a group of researchers are measuring pollutant levels and monitoring villagers' health. Although new stoves with chimneys reduced interior carbon monoxide (CO) levels significantly, children's actual exposure to pollutants like CO and smoke might not show the same reduction because they are exposed to pollutants while outside their home. This result is another example of how field conditions (a child going about his or her daily routine) do not match laboratory conditions (a measurement device in the kitchen). In addition, the article points out, performance improvements seen in the laboratory are rarely duplicated in the field because of differences in fuels, operator behavior, and so forth. The article compares and contrasts large-scale clean-stove programs in India and China. In the early 80s, both nations began distributing cleaner stoves. But while 150 million are still in use in China, almost none are still in use in India. One of the keys for China's success was to have several manufacturers design stoves to be produced on a large-scale in regional factories. In India, in contrast, stoves were made by local artisans and had poor performance and durability. (Note that the centralized model is being promoted by the Aprovecho Research Center, as my previous post explained.) Hopefully India has learned some lessons from their first program, because the nation is trying again, with a goal of distributing 150 million stoves over 10 years. To help create better designs, they have instituted a multi-million dollar "innovation prize." The article doesn't say how many prizes will be given out. Since previous designs have been incompatible with local fuels and uses, it would make sense to give out many prizes in different parts of the country to encourage locally-appropriate designs: in the rice-growing south, a prize for stoves that run on bio-gas from rice straw gasifiers; a prize for the best dung-fired stove; and so on. India is also including a research component in the program to learn more about the health impacts of the different components of the biofuel smoke (i.e., among carbon monoxide, fine particulate matter, polycyclic aromatic hydrocarbons, etc., which is the one that has the largest impact on health?). Ideally, they'll also include technical support for stove adopters, like regular visits to see how the stoves are working on the local fuels, help when something breaks, and so on. Distribution is critical: you can have the greatest, most robust, easiest to use stove, but if you can't get it to the people who need it, the exercise is pointless. In the past, nations have tried subsidy approaches — having the government pay 25% of the price, for example — but these can leave the poorest behind, those who can't scrape together $10 or $20 at a time. A better alternative might be small loans — microfinance — that spread out the payments over a year. Experts estimate that 600–800 million homes worldwide need improved cook stoves, so designers, policy-makers, and microfinance groups have plenty of opportunities to find the right design and distribution method. I've obviously left out a lot of details, so if you're interested in cookstoves, read the whole thing. |
