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The societal dimensions of domestic coal combustion : People's perceptions and indoor aerosol monitoringMdluli, Thulie Nomsa 23 October 2008 (has links)
Air pollution is one of many issues that have a direct impact upon the economy and
the well-being of society in South Africa. Domestic coal combustion contributes significantly
to the air pollution problem in the country. Both qualitative and
quantitative methods of data collection have been employed in this study. A
questionnaire survey was conducted in 100 households in Doornkop (Soweto) and
100 households in KwaGuqa (Witbank). The observations were carried out
simultaneously while the questionnaire surveys were being administered in both
study areas. Interviews were also held with Eskom (the Electricity Supply
Commission of South Africa) officials. Finally, the indoor concentrations and
elemental composition of respirable particulate matter (PM7) were measured in three
different types of households: electrified without coal burning, electrified with coal
burning, and un-electrified with coal burning.
The results show that township households, whether electrified or not, continue to
burn coal. In both study areas, 80 % of electrified households burn coal for space
heating and cooking. Although the major obstacles preventing people from
discontinuing domestic coal combustion are poverty and the ready availability and
social acceptability of coal, the social value of a fire inside township households
cannot be underrated. Previously developed coal-supply networks still exist in the
townships and makes coal utilisation very convenient. The findings also point to use
of multiple fuels in the communities studied. The key fuels used for domestic energy
supply are coal, electricity and paraffin. Emergent patterns of domestic coal
combustion, driven in part by various societal dimensions, are also observed. Further,
despite the previously observed increase in respiratory ailments in winter, township
residents do not think that such increases are linked to domestic coal combustion.
The study, as shown here, is in line with theories of the energy ladder which posits
that as people’s financial situations improve, their energy-use patterns change.
Indoor aerosol concentrations followed the same trends in all selected households
with morning and evening peaks. These peaks are directly related to the making of
coal fires. The highest aerosol levels, reaching a maximum of 2344.89 μg.m-3, are
recorded in the un-electrified coal-burning household. Aerosol concentrations are
slightly lower, averaging 1854.07 μg.m-3, in the electrified coal-burning household,
implying a slight decrease in the amount of coal burnt. The lowest aerosol
concentrations, averaging 478.74 μg.m-3, are recorded in the electrified household
with no coal-burning. Elemental analysis reveals that the biggest contributor to
respirable particles in KwaGuqa is soil dust followed by coal smoke, and then
emissions from neighbouring steel smelters, whilst traffic emissions are the lowest
contributor. Most importantly, it is people’s activities that determine the type and
levels of respirable aerosols that they are exposed to as compared to the fuel-use
patterns and types of fuels used in their household.
In conclusion, electrification might phase out domestic coal combustion in the long
term but only if the economic status of coal users improves. Alternatively, there is an
opportunity to reduce emissions by introducing a low-smoke solid fuel, however,
households will only use it if it is priced competitively and its heating and ignition
properties are similar to, or better than, those of coal.
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