Finally, it should be pointed out that, although modernization
and changes in efficiency in the use of energy – e.g., whether two
types of energy such as heat and electricity are produced from
one fuel sources (known as cogeneration or distributed generation)
– would affect CO2 emissions in those 12 major nuclear generating
countries, this paper does not take into account these factors in the
analysis. In addition, this study does not consider the so-called pollution
haven hypothesis for developing countries; that is, developed
(rich) countries that generally have high demand for environmental
quality tend to specialize in products that can be produced
cleanly, letting developing countries (e.g., China) produce more
pollution-intensive goods, thereby deteriorating environmental
quality. All these issues are beyond the scope of this study but
should be addressed in future research.