مصرف انرژی و رشد اقتصادی در امریکا مرکزی: شواهد از هم انباشتگی پانل و مدل اصلاح خطا

This study examines the relationship between energy consumption and economic growth for six Central American countries over the period 1980–2004 within a multivariate framework. Given the relatively short span of the time series data, a panel cointegration and error correction model is employed to infer the causal relationship. Based on the heterogeneous panel cointegration test by Pedroni (Pedroni, P., 1999. Critical values for cointegration tests in heterogeneous panels with multiple regressors. Oxford Bulletin of Economics and Statistics 61, 653–670; Pedroni, P., 2004. Panel cointegration: asymptotic and finite sample properties of pooled time series tests with an application to the PPP hypothesis: new results. Econometric Theory 20, 597–627), cointegration is present between real GDP, energy consumption, the labor force, and real gross fixed capital formation with the respective coefficients positive and statistically significant. The Granger-causality results indicate the presence of both short-run and long-run causality from energy consumption to economic growth which supports the growth hypothesis.

Since the initial study by Kraft and Kraft (1978) on the U.S. economy, the causal relationship between energy consumption and economic growth has been undertaken for a broad range of countries.1 An investigation of the energy consumption–growth nexus not only provides insights with respect to the role of energy consumption in economic development, but also provides a basis for discussion of energy and environmental policies. For instance, if energy consumption is a vital component in economic growth either directly or as a complement to other factors of production, energy conservation policies which reduce energy consumption may have an adverse impact on a country's growth prospects. Alternatively, if energy consumption is largely dependent on economic growth, energy conservation policies oriented towards the reduction in energy consumption may not have an adverse impact on a country's growth prospects. Indeed, as one might expect, the empirical literature on the energy consumption–growth nexus have yielded mixed results. As pointed out by Yu and Choi (1985), Ferguson et al. (2000), and Toman and Jemelkova (2003), the absence of any clear consensus on the relationship between energy consumption and growth can be attributed to the heterogeneity in climate conditions, varying energy consumption patterns, the structure and stages of economic development within a country, the alternative econometric methodologies employed, the presence of omitted variable bias along with varying time horizons of the studies conducted. The purpose of this study is to extend the empirical literature on the causal relationship between energy consumption and economic growth in the case of Central America. Historically, the economic base of the Central American region was largely dependent on agricultural exports, but more recently, the economic base of the region has diversified towards manufacturing and tourism. Though Central America is by no means the poorest region in the world, there is still a great deal of variation in real GDP per capita between countries. For example, real GDP per capita data (for 2004) ranges from a low of $817 per capita in Nicaragua to a high of $4330 per capita in Costa Rica.2 There is also variation in energy production and consumption in the region with roughly three-fourths of its total energy consumption imported.3 With respect to petroleum production, only Belize and Guatemala are oil producers but only on a small scale with limited refining capacity located in Costa Rica, El Salvador, and Nicaragua. Moreover, the Panama Canal as a transit center for oil shipments has declined over the years due to the canal's inability to service ultra-large crude oil tankers. However, this may very well change as the Panamanian government recently approved an expansion of the canal to accommodate larger tankers and as a consequence may also accommodate the transport of liquefied natural gas and coal.4 Indeed, the region relies upon petroleum imports to meet its consumption needs which ranges from 6,750 barrels per day in Belize to 88,030 barrels per day in Panama. Though Guatemala has proven natural gas reserves, there is no natural gas production or consumption in Central America. Likewise, there is no coal production in the region with the relatively small amount of coal consumption, primarily in Guatemala, Honduras, and Nicaragua, coming from coal imports. With respect to renewable energy sources, Central America is becoming an important producer of ethanol with a majority of ethanol exported to the U.S. Hydropower has been the dominate source for electricity production in the region. However, many of the newer power plants are utilizing thermal power rather than hydropower. In an attempt to integrate the energy infrastructure of the region, in December 2001 all seven Central American countries agreed to the Plan Puebla–Panama. In particular, the plan focuses on the integration of electricity markets and transmission grids, increasing the security of the region's energy supply, reducing electricity costs, and attracting foreign investment. In recent years, electricity production and consumption has increased substantially, approximately 80% higher than a decade ago which can be attributed to the region's economic expansion and electrification of previously underserved rural areas.5 Though the attempts by the Central American governments for greater integration of the region's energy sector will improve energy provision and efficiency, the region's efficiency in energy usage, measured by real GDP per unit of energy use still exhibits variation across countries with a low of 4.19 in Nicaragua to a high of 10.0 in Panama.6 On the environmental front, five of the seven Central American countries (Costa Rica, El Salvador, Guatemala, Honduras, and Panama with Belize and Nicaragua excluded) ratified and accepted the Kyoto Protocol to the United Nations Framework Convention on Climate Change. However, the evolution of the region's economic base towards manufacturing and tourism and the corresponding reliance on imported petroleum has resulted in problems with pollution and greenhouse emissions. Indeed, total carbon dioxide emissions from the consumption of fossil fuels vary substantially across countries from 0.9 million metric tons in Belize to 14.0 million metric tons in Panama. Adjusting for population and the size of the economy, carbon dioxide emissions measured in metric tons per capita ranges from 0.742 in Nicaragua to 2.80 in Belize while carbon dioxide emissions in kilograms per real GDP ranges from 0.348 in Costa Rica to 1.12 in Honduras. This overview of the region's level of economic development, composition of energy production and usage, and the environmental impact of energy consumption serves as a point of reference to examine the causal relationship between energy consumption and economic growth in the case of Central America. Section 2 briefly overviews the hypotheses related to the causal relationship between energy consumption and economic growth along with a summary of the previous studies on Central American countries. Section 3 discusses the data, methodology, and empirical results. Concluding remarks are given in Section 4.

In order to design effective energy and environmental policies, policymakers need to understand the relationship between energy consumption and economic growth. In the case of Central America, the data reveals that real GDP per capita varies across countries in the region along with variation in energy production and usage across countries as well. The region does not produce natural gas or coal with imported petroleum and hydroelectric power fulfilling the region's energy needs. Given the region's energy composition and level of economic development, this study employs a panel data set for six Central American countries (Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama) over the period 1980–2004 to explore the causal relationship between energy consumption and economic growth taking into account two other factors of production: capital formation and the labor force. Pedroni, 1999 and Pedroni, 2004 heterogeneous panel cointegration test reveals there is a long-run equilibrium relationship between real GDP, energy consumption, the labor force, and real gross fixed capital formation. This long-run relationship suggests that a 1% increase in energy consumption increases real GDP by 0.28%; a 1% increase in capital increases real GDP by 0.18%; and a 1% increase in the labor force increases real GDP by 0.61%. Furthermore, the estimation of a panel vector error correction model indicates the presence of both short-run and long-run Granger-causality from energy consumption to economic growth lending support for the growth hypothesis. The positive impact of energy consumption on economic growth suggests that energy consumption plays an important role in the growth process both directly and indirectly as a complement to labor and capital. Over thirty years ago Sprout (1977, p.291), commenting on the interaction between energy consumption and economic growth in Central America, stated “As yet there appears to be little awareness within the region of the role of fuel and power in economic growth, nor do governments show much sense of urgency in reassessing their energy supply and demand situation in a comprehensive and long-term manner”. Indeed, policymakers have demonstrated the importance of integrating the region's energy sector to enhance the operation of energy markets and the promotion of renewable energy sources (i.e. ethanol production). In light of the recent changes in the economic base of the region towards manufacturing and tourism, the results of this study reiterate the importance of energy consumption in the development of these industries and the region's growth prospects. However, policymakers need to continue to improve energy efficiency usage and reduce the long-run environmental consequences of the region's historic dependence on imported petroleum and its consumption.