انتشار گازهای گلخانه ای، مصرف انرژی و رشد اقتصادی:یک تحلیل هم انباشتگی پانل از دیدگاه بخش صنعت کانادا

This paper investigates the long-run and the causal relationship between greenhouse gas emissions, energy consumption and economic growth for Canadian industrial sectors over the period 1990–2007. The empirical findings suggest that in the long-run equilibrium, energy consumption has a positive and statistically significant impact on greenhouse gas emissions whereas a non-linear relationship is found between greenhouse gas emissions and economic growth, consistent with the environmental Kuznets curve. The short-run dynamics conveys that there is a unidirectional Granger causality running from energy consumption to greenhouse gas emissions; from economic growth to greenhouse gas emissions and a weak unidirectional causality running from greenhouse gas emissions to energy consumption; from economic growth to energy consumption. In the long-run however, there seems to be a weak one way causality flowing from energy consumption and economic growth to greenhouse gas emissions.

There is widespread agreement among energy economists and policy analysts in Canada and elsewhere that the ever-increasing energy demand is the major contributing factor to anthropogenic greenhouse gas emissions. Energy is essential to all economic activities, however, the increasing attention given to global warming and climate change has renewed spur to research interest in the relationship between environmental pollutants, energy consumption, and economic growth. Nowadays, mitigation assessment of greenhouse gas emissions has become an integral part of the national and international climate policy agenda. Since the mid-1990s, the Canadian industrial sector has experienced spectacular economic growth. Between 1990 and 2007, industrial energy consumption increased by 28.10%, from 2709.96 petajoules (PJ) to 3471.59 PJ. Accordingly, industrial energy-related greenhouse gas emissions rose by 24.13%, from 135.76 megatonnes of carbon dioxide equivalent (Mt CO2e) to 168.52 Mt CO2e. Over the same period, output grew by an average annual rate of 2.32%. In 2007, the industrial sector accounted for about 32% of Canada's total greenhouse gas emissions. In the Regulatory Framework for Air Emissions (2007), the Canadian government has designed a concrete and ambitious plan to reduce emissions of greenhouse gases in a number of heavy polluting industries. Under this legislation, the targeted sectors are requested to improve their emission-intensity by 6% each year from 2007 to 2010. This yields a reduction of greenhouse gas emissions per unit of production by 18% from 2006 levels in 2010. And then every year thereafter, a 2% annual reduction in emission-intensity is required. This mechanism contributes substantially to the government's commitment to reduce national absolute greenhouse gas emissions by 20% from 2006 levels by 2020. However, to curb the greenhouse gas emissions and to ensure the sustainability of the economic development, it is important to better understand the link between greenhouse gas emissions, energy consumption, and economic growth. In the literature, there have been three streams of research to explore the relationship between these variables. The first stream of research focuses on the relationship between economic growth and environmental pollutants and suggests an inverted U-shaped relationship between environmental degradation and per capita income/output. This relation is known as the Environmental Kuznets Curve1 (EKC). Several studies examined the linkage between economic growth and environmental pollutants. Recent studies include Coondoo and Dinda, 2002, Dinda, 2004, Dinda and Coondoo, 2006, Akbostanci et al., 2009 and Lee and Lee, 2009 among others. These empirical studies have been subject to specification bias due to omission of relevant variables. The second stream of research investigates the relationship between energy consumption and economic growth. As emphasized by Apergis and Payne (2009b), 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. Over the past few decades, the relationship between energy consumption and economic growth has been extensively investigated. Representative studies in this regards are Ghali and El-Sakka, 2004, Lee, 2005, Lee and Chang, 2008, Lee et al., 2008, Payne, 2009, Soytas and Sari, 2009, Apergis and Payne, 2009b, Apergis and Payne, 2010b and Chandran et al., 2010, to mention only a few. The last stream of research combines the two previous by examining dynamically the relationship between emissions, energy consumption, and economic growth, see for instance Soytas et al., 2007, Ang, 2007, Halicioglu, 2009, Apergis and Payne, 2009a, Apergis and Payne, 2010a and Ozturk and Acaravci, 2010 for comprehensive reviews. Most of these empirical studies focus on using aggregate level data to investigate the relationship between emissions, energy consumption and economic growth. Furthermore, some of these studies make use of time series data which is known to yield unreliable and inconsistent results due to the low power of the unit root and cointegration tests. The use of panel data may increase the sample size allowing for more accurate and reliable statistical tests. Therefore, there are very few empirical work on the topics that have made an attempt to gain statistical power through the pooling of information across units, alas, they have neglected to account for the presence of cross-section dependencies2 of the data. As has been documented in the literature, failure to adequately account for the presence of cross-section dependence in panel data study could lead to serious bias problem, see for instance O'Connell, 1998, Andrews, 2005, Pesaran, 2006 and Bai and Ng, 2010. This paper contributes to the literature by extending the long-run and the causal relationship between greenhouse gas emissions, energy consumption and economic growth to a panel of Canadian industries over the period 1990–2007. Our analysis covers the industries targeted by the proposed industrial regulations. These industries are responsible for about 56% of the total industrial greenhouse gas emitted in 2007. The aim of the paper is more specifically to determine the nature of the long-run equilibrium and the causal relationship between greenhouse gas emissions, energy consumption and economic growth by taking into consideration the hypothesis of cross-section dependence. To the best of our knowledge, there has never been an attempt to investigate the relationship between these variables within a trivariate framework by employing disaggregate level panel data and considering the presence of cross-section dependence. This study try to fulfil this gap. In this respect, we argue that the examination of the relationship between emissions, energy consumption and economic growth carried out in this paper may be of uttermost importance for policy-makers and decision-makers to better understand the energy–environment–growth dynamics in order to develop effective energy policies that will palliate the impacts of human activities, and thereby contribute to reduce emissions of greenhouse gases while preserving economic growth. The remainder of the paper is organized as follows. The next section gives a brief review of the existing literature. Section 3 describes the data used in the empirical study. The econometrical methodology and results are provided in Section 4. Section 5 concludes the paper.

The key focus of this study was to examine the long-run equilibrium and the existence and direction of a causal relationship between greenhouse gas emissions, energy consumption and economic growth in the context of 21 highly-polluting industries for the period 1990–2007. We began by investigating the long-run equilibrium relationship by means of the FMOLS technique proposed by Pedroni (2000). The FMOLS estimates indicate that for the panel of industries, there is a strong evidence of a long-run relationship between greenhouse gas emissions and energy consumption. Result indicates a 1% increase in energy consumption increases greenhouse gas emissions by 0.82%. Furthermore, a statistically significant non-linear relationship between greenhouse gas emissions and economic growth is found for the panel of Canadian industries. Within industries, almost all industries indicate that energy consumption has statistically significant impact on greenhouse gas emissions, however, results with respect to the relationship between economic growth and greenhouse gas emissions are not conclusive. The long-run equilibrium results presented in this paper is of great interest to both policy-makers and stakeholders since it addresses the industry-specific effects, i.e. it shows clearly in which industry energy consumption and/or economic growth is tied to greenhouse gas emissions. Next, we applied a panel vector error correction model to explore the causal relationship between the variables. The study established a short-run unidirectional Granger causality running from energy consumption and economic growth to greenhouse gas emissions. The short-run Granger causality running from economic growth to greenhouse gas emissions indicate that in the short-run industrial production have greater impact on industrial emissions. These findings suggest to improve the environmental quality, Canada needs to implement policies measures that may induce industries to adopt new technologies that help reduce air pollution. The study also finds a weak short-run unidirectional Granger causality running from economic growth and greenhouse gas emissions to energy consumption. Moreover, the absence of a short-run causality flowing from energy consumption to economic growth has major implications for energy policy in Canadian industrial sector. This result implies that policy measures promoting energy efficiency can be implemented without jeopardizing economic growth. And finally, the long-run dynamics conveys that there is a weak unidirectional causality running from energy consumption and economic growth to greenhouse gas emissions.