276 Energy and transport for thefuture
as Usual’. The figure illustrates the large transitions that have occurred
in energy sources in the past and those that will have to take place in the
future.
The following sections address how increased energy conservation
and efficiency can be achieved and what developments can be realised in
new renewable energy sources; these are the technical means through
which the necessary reductions in carbon dioxide emissions will be
achieved in the energy sector.World Energy Council scenarios
The World Energy Council (WEC) is an international non-governmental
organisation with representation from all parts of the energy industry and
from over ninety countries. The Council has developed four energy scen-
arios for the period to 2020, each representing different assumptions in
terms of economic development, energy efficiencies, technology transfer
and the financing ofdevelopment round the world.The WEC emphasises
that they have been developed to illustrate future possibilities and they
should not be considered as predictions.
All four cases assume that there will be significant environmental and
economic pressures to achieve major improvements in energy efficiency
compared to historic performance, although to different degrees within
the various economic groupings of countries. One of them, scenario
C, assumes very strong pressure to reduce the emissions of greenhouse
gases in order to combat global warming. Table 11.1 presents the detailed
assumptions underlying the four scenarios.
Table 11.1 refers to the ‘energy intensity’ (see box on page 272),
which is a measure of energy efficiency. When averaged over the world,
over the past fifty years it has been falling by about one per cent per year. A
more demanding rate of reduction in energy intensity than this is assumed
for all the scenarios; for case C, the ecologically driven scenario, the rate
assumedis considered very demanding indeed. The main difference
between the modified reference case B1 and the reference case B is that,
in B1, the rate of reduction of energy intensity assumed for the economies
in transition is less than in case B and for the developing countries is
only half that in case B.
With somewhat less detail, scenarios A, B and C have been extended
to the year 2100 (Figure 11.4). Global energydemand can be expected to
continue to increase, but by that time the availability of fossil fuels will
be more limited and new renewables will contribute substantially to the
energy mix for all scenarios. Some of the characteristics of the scenarios
out to 2100 are listed in Table 11.2 – similar details of the scenarios for
2020 are in Figure 11.6.