مصرف انرژی و رشد اقتصادی: شواهدی از 11 کشور جنوب صحرای آفریقا

The paper examines the causal relationship between energy consumption and economic growth for eleven countries in sub-Saharan Africa. Using the autoregressive distributed lag (ARDL) bounds test, the study finds that energy consumption is cointegrated with economic growth in Cameroon, Cote D'Ivoire, Gambia, Ghana, Senegal, Sudan and Zimbabwe. Moreover, this test suggests that energy consumption has a significant positive long run impact on economic growth in Ghana, Kenya, Senegal and Sudan. Granger causality test based on vector error correction model (VECM) shows bi-directional relationship between energy consumption and economic growth for Gambia, Ghana and Senegal. However, Granger causality test shows that economic growth Granger causes energy consumption in Sudan and Zimbabwe. The neutrality hypothesis is confirmed in respect of Cameroon and Cote D'Ivoire. The same result of no causality was found for Nigeria, Kenya and Togo. The result shows that each country should formulate appropriate energy conservation policies taking into cognizance of her peculiar condition.

Several studies taking advantage of the advances in time series analysis, have examined the causal relationship between energy consumption and economic growth with either income or employment used as a proxy for the latter1. However, to date empirical findings have been mixed or conflicting. While some studies found a unidirectional causality running from gross national product (GNP; others reported bidirectional relationship. Few others have reported evidence of neutrality of energy consumption and economic growth2. However, the general observation from literature is that most studies on the causal relationship between energy consumption and economic growth have been focused on the advanced economies and other industrialized economies. Not many studies have been reported in the case of Sub-Saharan Africa. Moreover, none of the known existing studies have used the Autoregressive Distributed Lags (ARDL) bounds test in examining the casual relationship between energy consumption and economic growth.3 Hence, the objective of the paper is to investigate the cointegration and causality relationships between energy consumption and income using ARDL bounds test and the Granger causality (GC) test based on vector error correction model (VECM). The knowledge of causation between energy consumption and economic has significant policy implications. For example, if a unidirectional Granger causality running from income to energy is obtained, it could imply that energy conservation policies might be implemented with little adverse or no effects on economic growth. In contrast, if unidirectional causality runs from energy consumption into income, reduction in energy consumption could precipitate a fall in income or employment. However, the finding of no causality in either direction otherwise called ‘neutrality hypothesis' could imply that energy conservation policies do not affect economic growth. The paper is organized as follows. Section 2 provides the methodology adopted in the work. Section 3 presents the empirical results. Section 4 provides the concluding remarks.

The paper examines the causality between energy consumption and economic growth for eleven sub-Saharan African countries, using ARDL bound tests and Granger causality test within the context of VECM framework. The ARDL result shows that energy consumption is cointegrated with economic growth in seven of the countries included Cameroon, Cote D'Ivoire, Gambia, Ghana, Senegal, Sudan and Zimbabwe. In addition, in few of the countries, the result suggests that energy consumption has a significant long run impact on economic growth, e.g. Ghana, Senegal and Sudan. Granger Causality test within the VECM framework shows bidirectional relationship between energy consumption and economic growth for Gambia, Ghana and Senegal. However, the Granger causality test shows that economic growth Granger cause energy consumption in the case of Sudan and Zimbabwe. In the case of Cameroon and Cote D'Ivoire, the Granger causality test shows no causality between energy consumption and economic growth.17 The Granger causality test within the VAR framework for countries where cointegration was not found shows unidirectional causality running from economic growth to energy consumption for Congo. However no causality in either direction was found in Nigeria, Kenya and Togo. What are the policy implications of these findings? One, in countries where bidirectional Granger causality or feedback between energy consumption and income was found, energy conservation policies aimed at reducing energy must be designed in such a way that they affect consumer demand without adversely affecting economic growth. Such a policy could be through an appropriate mix of energy taxes and subsidies that will help ensure efficient energy use so as to enhance economic growth. However, the bidirectional causality found in some of these selected countries calls for caution in the use of single equation regressions of income on energy for making econometric forecasts. In countries where evidence shows unidirectional Granger causality running from income to energy, it is possible to implement energy conservation policies with little adverse or no effects on economic growth. However, in those countries where causality runs from energy consumption to income, reducing energy consumption could lead to fall in income or employment. Finally, the results clearly show that African countries cannot adopt the same energy conservation policies. Each country needs to articulate appropriate energy conservation policies taking into consideration her peculiar characteristics. Finally, it is important to note that the reasons advanced for the different directions of causality in our work are only suggestive. Hence, ascertaining and finding those factors that can help to explain the disparity is no doubt another line of inquiry that will help us understand better the relationship between energy consumption and economic growth.