Whereas energy consumption in developed countries has continued to grow and currently accounts for 70 per cent of the world energy demand, two-thirds of future growth is expected to take place in developing countries (IEA 2002a). Much of this growth will be to satisfy basic energy needs. Roughly 54 per cent of the population in developing countries still lack access to modern, high quality energy sources and fuels, relying on traditional fuels such as wood, dung and agricultural residues for cooking and heating (UN Statistics Division 2005). At least 1 600 million people lack access to electricity in their homes (Smith and others 2004). If the anticipated growth in energy demand is met with our current energy mix, the risks range from adverse effects on ecosystem and
human health, through severe economic hardship as prices continue to increase, to implications for national and human security.
The challenge today is therefore to increase energy efficiency, and meet the rising demand by urgently promoting forms of energy that reduce or eliminate harmful emissions, without compromising energy needs – particularly those of the poor. Improved access to energy services is among the necessary ingredients of economic growth, including the eradication of extreme poverty and hunger as called for in the Millennium Development Goals (Table 1).
Modern energy services can help meet the basic human needs of nutrition, warmth, and lighting as well as reduce the burden of timeconsuming domestic labour – all of which also contribute to improvements in areas such as education and public health.Energy services also contribute to industrial
growth, enhanced productivity and access to global markets and trade. Access to modern fuels and electricity are particularly important to promote gender equality as women and young girls disproportionately shoulder the burden of lack of modern energy services for household use (UNDP 2005).
Many of the impacts of air pollution are global (Box 1). Pollution can travel great
distances and cause damage to human health and flora and fauna; acid rain; eutrophication of fresh water; and global and regional climate change. In some cases, the people who are worst affected by the negative impacts of energy-related emissions are the poorest, who have contributed the least towards them. To steer the world to safer patterns of production and use, decisive national and global policies are needed. These must be aimed at expanding access to energy services for the poor (including the use of cleaner fossil fuel and biomass technologies); controlling the growth in per capita energy demand through improved efficiency; and encouraging the use and further development of more sustainable energy technologies.
The energy and air pollution link
Emissions from fossil fuel and biomass burning account for most energy-related air pollution in most parts of the world. Energyrelated emissions are released through the entire spectrum of energy activities, from upstream emissions during fossil fuel extraction and production to end-use emissions from fossil fuels burned for transport, heating, cooking and the like. A wide range of gaseous and particulate compounds have adverse impacts and can be considered air pollutants – including particulate matter (PM), tropospheric (surface) ozone (O3), nitrogen dioxide (NO2) and nitric oxide (NO) (together known as nitrogen oxides or NOx), sulphur dioxide (SO2), carbon monoxide (CO), harmful levels of carbon dioxide (CO2), organic compounds and metals. Particulates are further defined by their diameter – smaller particulates of diameters less than ten micrometres (µm) (called PM10) and 2.5 µm (PM2.5) can penetrate deeper into the human lung and do more health damage.
These compounds have a range of harmful local, regional and global impacts. Climate change, often described as one of the biggest global challenges facing humankind today, has received considerable global attention from policy makers, scientists and the media. Whilst not the focus of this section, which deals with energy-related indoor, outdoor and transboundary air pollution, the fundamental energy sector transformation needed to reduce carbon dioxide and other greenhouse emissions overlaps in many ways with the measures needed to address air pollution problems. Globally, indoor air pollution levels from
solid fuel use are higher than outdoor air pollution. For example, typical levels of PM10 in homes using biomass energy range from 300 to 3 000 micrograms per cubic metre (µg/m3) (WHO 2002a), whereas even the most polluted cities rarely exceed 150 µg/m3 (Box 2). For comparison, the US Environmental Protection Agency’s (US EPA) annual air pollution guideline for PM10 is
50 µg/m3, and the EU guideline is 40 µg/m3.
The WHO, in a large-scale risk assessment that combined the results of many studies, compared the global burden of illness and premature death from major risk factors, including outdoor air pollution,
tobacco smoking, unsafe water and sanitation and others. The results indicated that indoor air pollution from solid fuel use is
the tenth major health risk in the world in terms of potentially preventable lost life-years (Figure 2), and may be responsible for
0.8–2.4 million premature deaths each year worldwide (Smith and others 2004).
In developing countries, indoor smoke from
solid fuels is estimated to be the fourth leading high mortality health risk (WHO 2002b). Urban air pollution, meanwhile, isestimated to be responsible for approximately 800 000 premature deaths every year (Cohen and others 2004). Despite these high figures, the negative impacts of these air pollutants have received little attention in many parts of the world for a variety of reasons, including insufficient information on the status of the damaging pollutants and their impacts, the costs to the economy of corrective action, and the fact that the affected populations are primarily the poor. Several dangerous pollutants such as ozone, benzene and small particulates are not monitored regularly in many countries. For instance, PM10 and ozone levels are measured regularly only in a few cities in the developing world (Molina and others 2004, Cohen and others 2004). Although a wide variety of technologies are available for monitoring air pollutants, economic and skill-related problems limit their use in many regions.