Page 289 - Materials Chemistry, Second Edition

13.4 Sensitivity analysis 287

FIG. 13.2 The sustainability rankings of the five electricity generation systems.

It is apparent that the electricity generation system based on ocean energy was recognized as
the most sustainable. In a similar way, the sustainability rankings of these other four alternative
electricity generation systems can also be determined, and the results are presented in Fig. 13.2.
It is worth pointing out that the ideal solutions with respect to the evaluation criteria may be
different in the ranking process when the number of the alternatives changes.
The ranking of ocean-energy-based electricity generation system as the most sustainable is
reasonable, because this scenario performs the best in all the four environmental criteria.
Meanwhile, it has very good public acceptability. The weights of global warming potential
(EN 1 ), acidification potential (EN 2 ), abiotic depletion potential (EN 3 ), and public acceptability
(S 1 ) are also very high; this is also the reason why the ocean-energy-based electricity gener-
ation system was recognized as the most sustainable.

13.4 Sensitivity analysis

In order to test the influences of the weights of the evaluation criteria on the sustainability
ranking of the five electricity generation systems, the following nine scenarios were studied,
and they are:
Scenario 0: using the weights determined by the interval best-worst method;
Scenario 1 (all the eight criteria play an equally important role): 0.1250 was set as the
weight for all the eight criteria; and
Scenarios 2–9 (a dominant criterion and seven equally important criteria): 0.3700 was set as
the weight of the dominant criterion and 0.0900 was set as the weights of the other seven
criteria. For instance, 0.3700 was set as the weight of EC 1 in scenario 2 and 0.0900 was set as
the weights of the other seven criteria.
The most sustainable electricity generation system determined under the conditions in the
above-mentioned ten scenarios is presented in Table 13.11. It is apparent that ocean-energy-
based electricity generation system was recognized as the most sustainable in all the ten sce-
narios. It means that the ocean-energy-based electricity generation system has a dominant
advantage compared with the other four electricity generation systems.

TABLE 13.11 The most sustainable electricity generation system in sensitivity analysis.
Scenarios 0 1 2 3 4 5 6 7 8 9
The most Ocean Ocean Ocean Ocean Ocean Ocean Ocean Ocean Ocean Ocean
sustainable