Energy, the Environment and Health

About half of the world's households use solid fuels (biomass and coal) for cooking and heating in simple devices that produce large amounts of air pollution—pollution that is probably responsible for 4–5 percent of the global burden of disease. The chief ecosystem impacts relate to charcoal production and fuelwood harvesting.

At the workplace scale, solid-fuel fuel cycles create significant risks for workers and have the largest impacts on populations among energy systems. In communities, fuel use is the main cause of urban air pollution, though there is substantial variation among cities in the relative contributions of vehicles and stationary sources. Diesel-fuelled vehicles, which are more prominent in developing countries, pose a growing challenge for urban health. The chief ecosystem impacts result from large-scale hydropower projects in forests, although surface mining causes significant damage in some areas.

At the regional scale, fine particles and ozone are the most widespread health-damaging pollutants from energy use, and can extend hundreds of kilometres     from their sources. Similarly, nitrogen and sulphur emissions lead to acid deposition far from their sources. Such deposition is associated with damage to forests, soils, and lakes in various parts of the world. At the global scale, energy systems ac count for two-thirds of human-generated green- house gas increases. Thus energy use is the human activity most closely linked to potential climate change. Climate change is feared to have significant direct impacts on human health and on ecosystems.

There are important opportunities for 'no regrets' strategies that achieve benefits at more than one scale. For example, if green-house gas controls are targeted to reduce solid fuel use in households and other energy sys-tems with large health impacts (such as vehicle fleets), significant improvements can occur at the local, community, and global scales.