| 摘要 |
��
It would be very natural that the patterns of energy consumption in both household and industry sectors change with either changes of industrial structures or changes of energy and environmental policies. According to the statistical data on energy consumption, the phenomenon of interfuel substitution in energy demand of industry sector has been visualized. For example, consumption share of petroleum has been declined. On the other hand, the trends of demand shares of electricity and natural gas have been increased gradually.
Furthermore, considering the security of stable energy supply and substitution of energy demand into environmental-friendly energy sources related to the United Nations Framework Convention on Climate Change(UNFCCC), the need for empirical researches on the interfuel substitution has getting more important to provide fundamental data in establishing energy and environmental policies.
Thus, this study analyzes the interfuel substitution in Korean manufacturing sector by considering petroleum, electricity, natural gas and coal.
The empirical model used in this study is static and dynamic linear logit models, instead of translog model, which have been widely used in many studies on the interfuel substitution because translog model has some shortcomings.
The linear logit model also contains time lag of input variable rather than that of a dependent variable for the explicit analysis of dynamic effect. Finally, static and dynamic logit models have been estimated using non-linear iterative two-step procedure based on the Zellner's seemingly unrelated regression method.
For the period of 1981-2001, using the data of consumption level and price of each energy source, we calculated and used the actual cost share of each energy source for the empirical tests. According to the empirical results, firstly, the own-price elasticities of energy sources are all negative and statistically significant.
Especially, the long-run elasticity of natural gas is -0.424, which is the largest among four sources, petroleum, -0.052, and both of price elasticities of electricity and coal are -0.024, which is relatively inelastic compared with those of other soures. Secondly, cross-price elasticities of fuels are all positive and statistically significant but the case of electricity and coal, which has a negative sign implying a complementary relation between them.
Lastly, the rate of dynamic adjustment to the change of energy prices is 0.026 suggesting that the speed of dynamic adjustment to the long-run equilibrium is very rapid.
The implication of the empirical results is summarized as follows: First, the fact of inelastic own-price elasticity of petroleum implies that the dependency of Korean manufacturing sector on petroleum will be persistent even in a sharp fluctuation of petroleum price. However, the substitution relationship between natural gas and petroleum is relatively largest compared with those of other sources.
Thus, it would be one of concerns in establishing environmental- friendly energy policies.
Lastly, according to the results of the trends of own-price elasticities as well as cross-price elasticities between interfuels, substitution into other fuels, especially into oil and coal, by the increase in the price of natural gas has been increased rapidly after 1997. This result contains very important implication on CO2 emission issue.
There are some limitations in the study. First, the period of analysis is not enough long to conduct some diverse tests. Especially, the data of gas are available only from 1989. Second, this study uses only static and dynamic logit models.
Thus, there is no empirical comparison between translog model and logit model.
The purpose of this study is to analyze the interfuel substitution in Korean manufacturing sector. However, we can also assess the effects of changes of energy and environmental policies such as deregulation of energy industry sector or the change of patterns of energy consumption related to UNFCCC on interfuel substitution.
These studies will remain for future researches.
83 pages. 30 refs., 10 figs., 17 tabs.
, Language: Korean |
