(b) Measuring Methods: For the energy sector, the amount of normal waste can most
easily be measured by weight as it leaves the energy production facility. In the case of
mining waste, which normally is stored on-site, the amount can be estimated based on
the quantity of coal or lignite extracted. The estimation method should be revised
regularly to take into account new extraction methods and changes in the seam.
Where relevant, the amount of incineration waste generated may be estimated based
on the ash content of the coal or lignite. It is important for this indicator to be policy
relevant; therefore, the different types of waste should be reported separately to
highlight the main areas where action is needed.
The waste generated should be presented in absolute terms (tonnes), which gives an
indication of the scale of the problem, and in terms of waste generated per unit of
energy produced, which allows the effects of reduction measures to be assessed. In
this case, it is important that the waste for each process be divided by the energy
resulting from that process only. Under no circumstances should any attempt be made
to aggregate all wastes and all energy produced from the different processes, as this
will result in double and treble counting of some energy sources and will present a
false picture.
The energy produced can be expressed in specific units of fuel produced (i.e. tonnes
for coal, lignite and petroleum; cubic metres for gas; MWh for electricity), or in
energy units (terajoules [TJ], MWh or toe, based on gross calorific value).
(c) Limitations of the Indicator: Solid waste generation from energy use,
particularly waste from mining activities, is not always monitored at source and may
have to be estimated based on coefficients. In this case, the waste generated per unit
of energy produced will remain unchanged, unless the coefficients are changed. The
indicator does not distinguish between toxic and hazardous wastes, and those that are
more benign. It is often confused with the amount of solid waste disposed of, which is
measured by recording the weight or volume of waste disposed of at a disposal or
treatment site.
