再生能源與經濟成長因果關係之實證分析

Abstract

全球在積極發展再生能源以降低碳排放量的同時，各國政府及學者們相當關注發展再生能源是否會影響一國的經濟發展。目前多數文獻僅分析再生能源與經濟成長間的因果關係，並未考慮一國之經濟規模是否會影響此結果。因此，本研究欲透過向量自我迴歸模型（Vector Autoregression, VAR）及縱橫平滑移轉迴歸模型（Panel Smooth Transition Regression Model, PSTR）建構縱橫向量自我迴歸模型（Panel Vector Autoregression Model, PVAR）及縱橫平滑移轉向量自我迴歸模型（Panel Smooth Transition Vector Autoregression Model, PST-VAR），用以評估再生能源使用率與經濟成長率在不考慮經濟規模及考慮經濟規模時的因果關係，以解決過往文獻較無關注的點。 實證上，採用217個國家，在1990-2019年的期間資料進行估計。實證結果顯示，在PVAR模型下，經濟成長率對再生能源使用率具有顯著的單向因果關係，且為負向影響；而在考慮門檻變數（人均GDP）的PST-VAR模型下，經濟成長率對再生能源使用率亦有顯著的單向因果關係，且當人均GDP超過15,129美元時，將由負向影響轉為正向影響。 本研究結果顯示，當一國經濟規模（人均 GDP）較小時，提高經濟成長的同時將有可能抑制再生能源之發展；然而，當一國經濟規模達一定水準時，將使該國經濟成長對再生能源有顯著之正向影響。由本研究結果推斷，當一國之經濟規模較小時，經濟成長動能主要依靠技術較成熟且較便宜的傳統能源，因此要使該國經濟成長，將有可能抑制再生能源的發展；而當一國經濟規模較大時，該國較有豐富的資金及純熟的科技來發展再生能源，因此當經濟成長的同時亦會帶動再生能源的發展。

This study constructs panel vector autoregression (PVAR) and panel smooth transition vector autoregression (PST-VAR) models, using the vector autoregression (VAR) model and the panel smooth transition regression (PSTR) models, to evaluate the causality between renewable energy and economic growth, both with and without considering economic scale. Empirically, the data from 217 countries during the period 1990-2019 are used for estimation.The empirical results show that, under the PVAR model, the economic growth rate has a unidirectional causality effect on renewable energy, and it has a negative impact. In the PST-VAR model that considers a threshold variable (GDP per capita), the economic growth rate has unidirectional causality effect on renewable energy, and when the per capita GDP exceeds US$15,129, the negative impact will turn into positive impact. This study demonstrates that when a country’s economic scale (GDP per capita) is less than a certain value, it may reduce the development of renewable energy while increasing economic growth; however, when a country’s economic scale reaches a certain level, it will increase the country’s economic growth. Significant positive impact on renewable energy. According to the results of this study, it is inferred that when a country’s economic scale doesn’t reach a certain level, the economic growth momentum mainly relies on traditional energy sources with relatively mature technology and cheap prices. Therefore, in order to make the country’s economy grow, it will be possible to reduce the development of renewable energy. While, when the country’s economic scale reaches a certain level, the country’s capital and technology will help to develop renewable energy. Therefore, when the economy grows, it will also drive the development of renewable energy.