مصرف برق و رشد اقتصادی:یک سری تجربه زمانی برای 17 کشور آفریقایی
|تعداد صفحات مقاله انگلیسی
|9 صفحه PDF
نسخه انگلیسی مقاله همین الان قابل دانلود است.
هزینه ترجمه مقاله بر اساس تعداد کلمات مقاله انگلیسی محاسبه می شود.
این مقاله تقریباً شامل 6619 کلمه می باشد.
هزینه ترجمه مقاله توسط مترجمان با تجربه، طبق جدول زیر محاسبه می شود:
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Energy Policy, Volume 34, Issue 10, July 2006, Pages 1106–1114
While the availability of electricity by itself is not a panacea for the economic and social problems facing Africa, the supply of electricity is nevertheless believed to be a necessary requirement for Africa's economic and social development. This paper tests the long-run and causal relationship between electricity consumption per capita and real gross domestic product (GDP) per capita for 17 African countries for the period 1971–2001 using a newly developed cointegration test proposed by Pesaran et al. (2001) and using a modified version of the Granger causality test due to Toda and Yamamoto (1995). The advantage of using these two approaches is that they both avoid the pre-testing bias associated with conventional unit root and cointegration tests. The empirical evidence shows that there was a long-run relationship between electricity consumption per capita and real GDP per capita for only 9 countries and Granger causality for only 12 countries. For 6 countries there was a positive uni-directional causality running from real GDP per capita to electricity consumption per capita; an opposite causality for 3 countries and bi-directional causality for the remaining 3 countries. The result should, however, be interpreted with care as electricity consumption accounts for less than 4% of total energy consumption in Africa and only grid-supplied electricity is taken into account.
Despite the immense energy potential Africa possesses, energy consumption in general and electricity consumption in particular is very low (Karekezi and Kimani, 2002; Economic Commission for Africa (ECA), 2004).1 The average African is still using less energy than the average person used energy in England more than a century ago (Davidson and Sokona, 2002). The disparity in electricity consumption, let alone between Africa and the rest of the world even among African countries themselves, is glaring. Even more glaring is the wide disparity within African countries themselves. For instance, in Ghana 62% of the urban population has access to electricity while only 4% of the rural population has access to electricity (Saghir, 2002). Electrification rates range from as low as 3.7% in Uganda, 4.7% in Ethiopia and 5.0% in Malawi to as high as 45% in Ghana, 50% in the Ivory Coast and 66% in South Africa (International Energy Agency (International Energy Agency (IEA), 2002). Similarly, electricity power consumption per capita ranged from as high as 556 kWh in Zambia, 698 kWh in Gabon and 845 kWh in Zimbabwe to low as 22 kWh in Ethiopia, 47 kWh in the Democratic Republic of the Congo and 58 kWh in Tanzania (World Bank, 2003). The average per capita electricity consumption for Sub-Saharan Africa (excluding South Africa) was 112.8 kWh in 2000, representing a mere 5% of the world average.2 With only 23% of its population electrified compared to the world average of 73%, Africa has the lowest electrification rate of any major world region (IEA, 2002). More than 500 million Africans are still without access to electricity. To make matters still worse, while the world electricity per capita consumption has been rising steadily over the past three decades, Sub-Saharan Africa's per capital electricity consumption has been stagnant. In fact, the electricity per capital consumption of Sub-Saharan African countries (excluding South Africa) declined from 132.6 kWh in 1980 to 112.8 kWh in 2000 (World Bank, 2003). To aggravate the problem further, less than 10% of the Sub-Saharan Africa population has access to electricity, with electricity largely confined to the energy-intensive sub-sector of the commercial and industrial enterprises and to the high-income households, while the electrification of the rural and urban poor is ‘woefully inadequate’ or non-existent (Karekezi, 2002). The number of people without electricity in Africa has doubled in rural areas and tripled in urban areas in the last 30 years. Most of the people without access to electricity in 2030 will still be in Sub-Saharan Africa (650 million) and South Asia (680 million) (IEA, 2002), with the population of Sub-Saharan Africa without electricity increasing steadily until 2025. It is estimated that at the rate of connections of the past decade, it would take more than 40 years to electrify South Asia and almost twice as long for Sub-Saharan Africa (IEA, 2002). If the transition to modern fuels is usually complete by the time per capita income reaches US$1000–1500 (Toman and Jemelkova, 2003), Sub-Saharan Africa has a long way to go: “… access to electricity for the poor is a dream that is unlikely to be realised in the near future” (Karekezi and Kimani, 2002). The purpose of this paper is to investigate the long-run and causal relationship between electricity consumption and economic growth for 17 African countries using a newly developed cointegration test due to Pesaran et al. (2001) and using a modified version of the Granger causality test proposed by Toda and Yamamoto (1995). Cointegration is preferred over conventional methodology for two main reasons. In the first place, the relationship found using ordinary regression analysis of time series data could be spurious as the time series properties of the data are not taken into consideration. Granger and Newbold (1974) have shown that when using non-stationary data, standard statistical t- and F-tests are misleading. In a spurious regression, there is no relationship between the series under consideration. Tests of ordinary regression to time series data may often suggest a statistically significant relationship between variables, where none in fact exists. Cointegration provides a way of avoiding the misleading inference associated with a spurious regression (see Enders, 2004). Moreover, while the use of ordinary regression is useful in detecting correlation between two or more variables, it cannot detect whether there is a long-run or a casual relationship between or among the time series data under consideration; correlation does not imply causation. From a policy perspective, it is important to know the direction of causality, say, between energy consumption and economic development, so that energy conservation measures may or may not be taken depending on the direction of causality between energy consumption and economic growth. Despite the burgeoning literature on the study of causality between electricity consumption and economic growth, there are not many time series studies concerning African countries (see Jumbe, 2004). Apart from filling this gap, we focus on electricity for two other reasons. While 89% of Sub-Saharan people rely for their energy consumption on biomass, long-term time series data for biomass are only available since 1994 (IEA, 2002). Electricity seems to be the only sub-sector where long-term time series data are available from the World Bank, World Development Indicators (2004), and this is one of the factors that motivated this paper. More importantly however, we focus on electricity because of the pivotal role it plays in economic development and technological progress. While the availability of electricity is not by itself a panacea for the economic and social problems facing Africa, the supply of electricity is nevertheless believed to be a necessary requirement for Africa's economic and social development (IEA, 2002). Even at the individual level, research shows that electricity service appears to be one of the most important services for improving the welfare of the poor individual (IEA, 2002). At the national level, in this era of the digital economy, it is really difficult to envisage development without the use of electricity. Electricity and other modern energy sources are necessary requirements for economic and social development (IEA, 2002). “No country in the world has succeeded in shaking loose from subsistence economy without access to the services of modern energy provides” (World Bank, n.d.). Apart from the physical availability of energy, change in the quality of energy service is one of the most important drivers of economic productivity (see Toman and Jemelkova, 2003). The process of economic development necessarily involves a transition from low levels of energy consumption to higher levels where the linkages among energy, other factor inputs and economic activity change significantly as an economy moves through different stages of development (see Burney, 1995; Toman and Jemelkova, 2003). Furthermore, as the economy progresses, commercial fossil fuels and ultimately electricity becomes predominant (see Toman and Jemelkova, 2003). Thus, although currently Sub-Saharan African countries consume a mere fraction of the electricity consumed by industrial countries, rapid urbanization combined with economic growth is likely to accelerate the energy transition from traditional to commercial energy use (IEA, 2002). Statistical evidence also suggests that electricity consumption is strongly correlated with wealth and lack of electricity is strongly correlated to the number of people living below $2 per day (IEA, 2002). The elasticity of power system capacity to GDP in developing countries is about 1.4 (Munasinghe and Meir, 1993). Ferguson et al. (2000) also found that for developed countries, there is a strong correlation between increases in wealth over time and increases in energy consumption. Moreover, there is a stronger correlation between electricity use and wealth creation than there is between total energy use and wealth (Ferguson et al., 2000). The experience of developed countries also shows that the electricity supply sector played a crucial role in their economic development not only as a key input in their industrial development but also as a key factor in improving the quality of life of their people (Rosenberg, 1998). Further, increasing electricity use has been identified as an important source of productivity improvement in developed countries and it is the sector that is currently fuelling the ‘‘new digital economy’’ (Ebohon, 1996; Rosenberg, 1998). For developing countries it has also been found out that there is a significant correlation between export diversification and per capita electricity consumption and electricity production per worker in Africa (ECA, 2004). Countries with high per capita electricity consumption are expected to have lower energy costs and vice versa. Export diversification is positively associated with per capita electricity consumption and electricity production per worker, implying that countries that have more access to electricity tend to have a relatively lower cost of energy and are more diversified (ECA, 2004). The evidence suggests that good and reliable energy infrastructure is a prerequisite for export diversification and sustained growth, but the inability of many African countries to provide good and adequate energy services has been a major constraint for their export diversification and growth (ECA, 2004). It is now widely accepted that if Sub-Saharan African countries are to pursue sustained economic growth which is vital to their efforts of eradicating poverty and social development, the availability of financially feasible, reliable and efficient supply of electricity is crucial (Turkson and Wohlgemuth, 2001). Further, the expansion of electricity supply is important for Sub-Saharan Africa in order to minimize the consumption of traditional fuel (biomass) that has been responsible for the massive deforestation, desertification and the health problems associated with wood fuel and charcoal consumption (IEA, 2002). The ubiquitous electricity restructuring that is currently taking place in many African countries is part of the process of the recognition that electricity can play a pivotal role in Africa's social and economic development.3 Implicit in this restructuring process is the assumption that investment in electricity and the drive towards making the electricity sector more efficient can promote economic growth. Therefore, knowledge of the direction of causality between electricity consumption and economic growth is of prime importance if appropriate energy policies and energy conservation measures are to be devised. Central to the debate is whether electricity consumption stimulates, retards or is neutral to economic growth. Some argue that modern energy use is a prerequisite for economic, social and technological progress where it complements labour and capital in the production process (see, Ebohon, 1996; Templet, 1999). For the proponents of the above hypothesis, lack of energy is a limiting factor to economic growth and technological progress. They believe that electricity has been a major source of betterment of the standard of living of advanced countries and it has played a crucial role in the technological and scientific advancement of these countries (see, Rosenberg, 1998). Even in poor countries, it has been found out that the use of electricity is associated with improving the health and educational standards of the poor (IEA, 2002). Others however contend that the role of energy is minimal or is neutral to economic growth. This is because the cost of energy is very small as a proportion of GDP and thus energy consumption is not likely to have a significant impact on output growth. Moreover, they argue that as the economy grows, its production structure is likely to shift to the service sector that is less energy intensive relative to the industrial sector (see Ghali and El-Saka, 2004). This, however, may not be true for the electricity sector as the evidence from the US experience suggests that the US economy is becoming simultaneously less energy intensive but more electricity intensive (Rosenberg, 1998). The above contrasting hypotheses have motivated many researchers to seek the direction of causality between electricity consumption and economic development. The empirical evidence is mixed, reflecting the divergent hypotheses with causality ranging from bi- to uni-directional (see Fatai et al. 2004; Jumbe, 2004; Wolde-Rufael, 2004; Ghali and El-Saka, 2004). For instance, Yang (2000) found bi-directional causality between electricity consumption and economic growth for Taiwan as did Morimoto and Hope (2004) for Sri Lanka; Yoo (in press) for South Korea; Glauser and Lia (1997) for South Korea and Singapore and Jumbe (2004) for Malawi. Causality running from economic growth to electricity consumption was found for India by Ghosh (2002); for Australia by Narayan and Smyth (2005) and by Fatai et al. (2004) and for the USA by Thoma (2004). In contrast, uni-directional causality running from electricity consumption to economic growth was found by Shiu and Lam (2004) for China and by Wolde-Rufael (2004) for Shanghai. These conflicting evidences have major implications for energy policy. If there is a unidirectional causality running from electricity consumption to economic growth, reducing electricity consumption could lead to a fall in economic growth (see Asafu-Adjaye, 2000). In contrast, if there is a uni-directional causality running from economic growth to electricity consumption, it could imply that policies for reducing electricity consumption may be implemented with little or no adverse effect on economic growth. On the other hand, if there is no causality running in any direction between electricity consumption and income, reducing electricity consumption may not affect income and energy conservation policies may not affect economic growth (see Asafu-Adjaye, 2000; Jumbe, 2004; Yoo (in press)). In contrast, if there is a bi-directional causality, economic growth may demand more electricity while more electricity use may induce economic growth; electricity consumption and economic growth complement each other and energy conservation measures may negatively affect economic growth. The diversity of the empirical findings, together with the important role electricity consumption plays in economic development, not only necessitates further research but also new methodologies for testing the relationship between electricity consumption and economic growth. With this objective in mind, the rest of the paper is organized as follows. An outline of the methodology is presented in Section 2 followed by the empirical evidence presented in Section 3. Some concluding remarks are outlined in Section 4.
نتیجه گیری انگلیسی
In this paper, a recently developed cointegration and a modified version of the Granger causality tests were applied to investigate the long-run and causal relationship between real GDP per capita and electricity per capita consumption for 17 African countries for the period 1971–2001. Long run cointegrating relationship between the two series could be detected only for 9 countries, while causality for only 12 countries. This paper did not provide a definite stand on the existence or non-existence of the causal relationship between electricity consumption and economic growth, but our results show the following: (1) past values of economic growth have a predictive ability in determining present values of electricity consumption in some countries, (2) past values of electricity consumption have a predictive ability in determining the present values of economic growth; (3) there was feedback in some countries and (4) there was a lack of causal relationship for some countries. What the evidence may suggest is that there may be a number of factors at work that differ significantly across countries that account for the different directions of causality detected in this paper. Finding some of these factors that can help to explain this disparity may be another line of inquiry that can help us understand the relationship between electricity consumption and economic development. It is also important to note that the results of this study should be interpreted with care as electricity consumption not only accounts for a very small share of total energy consumed but is also confined to the urban and commercial and industrial but denied to the substantial majority of people in Africa. In addition, non−grid electricity consumption, which plays a significant role especially in small businesses and medium−sized enterprises development, is not taken here into consideration. The challenge of providing adequate and reliable energy cannot be divorced from the other challenges Sub−Saharan African is facing. Poverty and poor access to modern energy are intractably linked and cannot be divorced from the many challenges Africa must tackle. Africa's energy problem is partly a result of the continent's macroeconomic mismanagement. Without improving the management of the economy and reducing the role of the state that has been blamed for Africa's economic ills, it is difficult to envisage how the energy challenges facing African countries can be addressed. The twin problems of low accessibility and lack of financial resources cannot be solved without drastic and fundamental changes to Africa's energy policy. Scarcity of energy supply is not the fundamental problem Sub−Saharan Africa is facing but its management is. It is encouraging to see that Africa is trying to make strides in restructuring its power sector industry with the view to making this sector efficient and accessible. However, without making the environment conducive to attracting the huge financial requirement needed to address the energy problem, African will remain without modern electricity for many years to come. It was beyond the scope of the paper to investigate the impact of the current wave of electricity restructuring that is sweeping Africa, but it would be interesting to see if these policy changes have made any impact on the accessibility and efficiency of the electricity sector in Africa. Unless the infrastructure necessary for modern supply of electricity and other forms of modern energy is firmly laid down, the talk about making electricity a driving force in Africa's economic development and an instrument for alleviating poverty and deprivation is naïve at best and a deliberate deception at worst.