The burning of solid fuels in the home is another major contributor to ill health globally. In 1992, the World Bank classified indoor air pollution as one of the four most critical environmental problems in developing countries (44). Indoor air pollution can weaken the body’s defenses and damage the lungs; these factors contribute to acute lower respiratory infections, chronic lung disease, lung cancer, asthma, low birth weight, blindness, and heart disease (45) (46). Nearly 100 developing countries rely on biomass fuels for some of their residential energy needs, according to a new World Resources Institute (WRI) estimate. In countries where use of smoky fuels is high, risks to health are likely to be high as well. Indeed, WHO recently estimated that indoor air pollution may be responsible for as many as 2.8 million deaths each year, making it one of the largest environmental risk factors of any kind (47).
In the short term, one way to reduce indoor air pollution is to improve household ventilation, but this strategy has obvious limitations and often worsens outdoor air quality. A more effective approach is to promote the use of improved stoves that remove the smoke from the house through a flue or chimney. In the past 20 years, hundreds of improved stove programs have been implemented throughout the developing world (48).
Although most of these programs had as their chief objective improved fuel efficiency rather than smoke removal, studies have shown that a well-designed, well-built, and well-maintained stove can reliably lower indoor air pollutants from cooking to levels 10 to 40 percent of those in kitchens with open fires (49). However, it is difficult to design and disseminate improved stoves that are affordable to the families who need them most. Furthermore, these improved stoves mainly serve to put the smoke outdoors, which can result in high levels of neighborhood air pollution.
Thus, improved stoves should be seen as an interim solution in the transition to less polluting and more efficient liquid fuels – such as kerosene and liquefied petroleum gas (LPG) – and electricity. This move up the energy ladder to fossil fuels for domestic uses typically occurs as incomes grow. But this transition to cleaner fuels may be impeded by the scale of poverty today and the number of people who rely on biomass fuels. Indeed, even in east Asia and the Pacific, a region that has experienced rapid economic growth, biomass fuels still account for 33 percent of energy supplies; use is expected to decrease by only 50 percent over the next 15 to 25 years (50).
National governments can help facilitate this transition to cleaner household fuels. Poor families can benefit from policies that reduce the upfront cash costs of new appliances (such as improved stoves or LPG bottles) or of obtaining electricity connections. Such policies can be implemented through programs that provide innovative credit; offer simple, low-cost service connection for electricity and LPG; and spread connection costs over a long period to reduce monthly outlay. In the electricity sector, the urban poor can benefit from “life-line” rates – charging consumers who use very little energy less than those who use more. Thailand, for instance, has adopted this approach. As a result, the urban poor pay less than wealthier households for lighting, and the country has near-universal electricity service, although many people still rely on biomass fuels for cooking (51).
The benefits of encouraging this energy transition extend beyond reductions in indoor air pollution. The time that would have been spent collecting fuelwood could instead be devoted to child care, agriculture, and income-generating activities. In addition, reduced use of wood fuels might also result in less deforestation, soil erosion, and accompanying losses in soil fertility (52).<–! Chapter 3 notes not entered –>