Page 30 - Module_6_en

Module Each of these cases is obviously a caricature; most scenario exercises will include some combination
6 of these, and certain cases are of less interest than others. The lack of both existing relevant

policies and a preconceived vision in cases g and h make it highly unlikely that either would be
undertaken in isolation. However, they might be used as extensions to cases d and e, respectively,

whereby new policies are identified in the process of testing existing ones. Given their inclusion
of preconceived visions, cases a, b, e, and f lend themselves to backcasting exercises, but they can
9-12 December, 2013 also be addressed in forward-looking exercises when the targets are not used to limit the set of

scenarios to be considered. With the latter, they are not significantly different from the equivalent
cases without preconceived visions (i.e., c, d, g, and h respectively). Finally, cases b, d, f, and h, by
exploring policies that do not “determine” the scenario, can be pursued without a full scenario

development process if scenarios already exist within which these policies can be adequately
assessed.

Several concrete examples of where scenario exercises have been used, and how they can be seen to
fit within this schema, are provided below.

? Testing policies to limit pollutant emissions from the power sector in the United States 2

The Energy Information Administration (EIA) in the United States analysed the potential costs and
impacts of various existing policies that sought to limit emissions of four pollutants from electricity
generators, sulphur dioxide (SO ), nitrogen oxides (NOx), carbon dioxide (CO ) and mercury
2
2
(Hg), in four different scenarios. Since there were existing policies and clear targets, but other
basic conditions were held fixed (e.g., overall economic growth), this serves best as an example
of case b above. The analysis showed emissions could be significantly limited for all pollutants, if a
substantial effort was made by industry, and this helped to illustrate the nature and scale of the
effort depending on the scenario. It also indicated that the increase in energy costs and other
economic impacts of the policies under investigation would decline over time.

? Identifying policies to achieve a 60 per cent reduction in carbon emissions by 2050 in the United
Kingdom
The UK Department of Trade and Industry has used the Royal Commission on Environmental

Pollution’s target of a 60 per cent reduction in carbon emissions by 2050 as a desired vision of the
future, and has used scenarios to help identify possible paths to meet this target. Since the policies
were not clearly specified beforehand, but a target did exist and key scenario conditions were held
fixed, this is best seen as an example of case f but also a and e, inasmuch as some particular policies
were tested. This work yielded a number of new policy initiatives and measures to achieve this

2. Note that a similar approach was used by the OECD in their second Environmental Outlook (OECD 2008)

28 Scenario Development and Analysis