کارایی فنی سیستم های اقتصادی 15 کشور عضو اتحادیه اروپا بر اساس مصرف انرژی
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|8639||2013||9 صفحه PDF||سفارش دهید||5769 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Energy Policy, Volume 55, April 2013, Pages 426–434
In the present study, Data Envelopment Analysis is used to determine the Technical Efficiency index of EU-15 countries from 1980 to 2008, using cross-country comparison. Technical Efficiency index represents the capacity of an economy to produce a higher level of Gross Domestic Product for a given level of total energy input. The level of the Technical Efficiency index is determined from the energy mix (fossil fuels, non-fossil fuels, nuclear energy) of each country and depends on the maximization level of the production of the Gross Domestic Product of the economic system, without waste of energy resources. The current study is applied in the case of the EU15 countries. Its scope is to highlight the differentiations of country classifications before and after the integration of nuclear energy in the energy mix of each country. The main result is that the integration of nuclear energy as an additional input in the energy mixture affects negatively the Technical Efficiency of countries. Also, when an economy achieves a decrease of the energy consumption produced from fossil fuels, and a better exploitation of renewable energy sources, clearly improves its capacity to produce more output with the given levels of inputs.
The increasing share of renewable forms of energy in a country's energy mix is a necessary but not a sufficient condition for the sustainability of economic system. This is due to the increasing energy demand, which cannot be met only from renewable resources. The maintenance of high levels of energy efficiency (EE) is essential to ensure the satisfaction of the energy needs of a country. Based on the definition provided by the World Energy Council (WEC), EE encompasses all changes leading to a reduction in the energy used for a given energy service (heating, lighting,…) or level of activity. This reduction in the energy consumption is not necessarily associated to technological changes, since it can also result from a better management or improved economic conditions of the sector, e.g. overall gains of productivity (WEC, 2011). Depending on the research discipline, the concept of EE can be different. In economic terms, it encompasses all changes resulting in a decrease of the amount of energy used to produce one unit of economic activity (e.g. the energy used per unit of GDP or value added) or to meet the energy requirements for a given level of comfort. In this case, energy efficiency is associated with economic efficiency and includes technological, behavioral and economic change (WEC, 2011). In the present study the concept of Technical Efficiency index (ΤΕ), as defined by the Data Envelopment Analysis (DEA) method for constant returns to scale, is applied in the case of energy efficiency of EU-15 countries. The Data Envelopment Analysis (DEA), developed by Charnes et al., 1978, is an alternative non-parametric approach based on a model of linear programming for assessing efficiency and comparative analysis of Decision Making Units (DMUs), in cases of constant (Charnes et al., 1978 and Thanassoulis, 2001) or variable (Banker et al., 1984 and Thanassoulis, 2001) returns to scale. In the DEA model of Constant Returns to Scale (CRS) the output y change is proportional to the input x (Charnes et al., 1978). In the DEA model of Variable Returns to Scale the output y increases with the increase of input x, but either less (descending returns to scale), or more (increasing returns to scale) than the increase of x (Banker et al., 1984). The concept of TE is an output maximization linear programming problem for constant inputs (Charnes et al., 1978 and Thanassoulis, 2001). The concept of TE is in line with the concept of energy efficiency, since only the energy resources (fossil fuels, non-fossil fuels, nuclear energy (NE)) are considered to be the inputs of the economic system. However, the TE index gives more complex information, since it is not limited to the energy efficiency levels of a single resource or the total energy input. On the contrary, it incorporates the specificities of the composition of the energy mixture of each country. Moreover, the methodology of TE index determination allows the investigation of the effects of nuclear energy on efficiency levels, as the index is calculated before and after the integration of nuclear energy in the energy mix of countries. Nuclear power corresponds to 14% of the total energy consumption of European Union in 2006 (EEA, 2006). Nuclear energy is very cost effective (NEA, 2001) and emits much fewer greenhouse gases than the production of electricity from coal or other traditional power plants (NEA, 2001). However, nuclear energy has specific dangers. Though nuclear energy does not release greenhouse effect gases, it produces radioactive waste products. This radioactive waste must be stored for a long period of time in specific conditions (Ferguson, 2007 and Cochran et al., 2005). Also, no matter how sophisticated technology is used, several accidents in nuclear power plant occurred (for example, the 1979 Three Mile Island accident in Pennsylvania, the Chernobyl Disaster of 1986, in actual Ukraine, or even the recent Fukushima, Japan, accident of March 2011). The social, political, economic, psychological and health consequences of those accidents are significant. The present study is based on a cross section data analysis of EU-15 countries. The Technical Efficiency index (ΤΕ) is used as a measure of efficiency of DMUs (which are the economic systems of EU-15 countries) based on energy consumption and is determined by taking into account the composition of the energy mixture of each country. The total input entered in the DEA model is the weighted sum of different types of energy. The disaggregation of total energy consumption into three different forms (fossil, non fossil fuels and nuclear energy) is an essential prerequisite for the classification of the countries based on TE index, before and after the integration of nuclear energy. Consequently, the degree of efficiency of each country is determined by the major shifts towards an energy-intensive mix. The degree of contribution of nuclear energy on TE levels of energy consumption is estimated for the efficiency levels of EU-15 countries before and after the integration of nuclear energy.
نتیجه گیری انگلیسی
In this study, the method of transformation of inputs into outputs, and hence the degree of efficiency of EU-15 countries, is determined by the dependence of the economic activity (GDP growth) from the consumption of fossil or non-fossil fuels and nuclear energy. The present work identifies the differentiation of efficiency levels and therefore the changes in the classification of the countries according to TE index before and after the integration of nuclear energy. The target is to highlight the positive or negative contribution of different energy sources (fossil, non-fossil fuels, nuclear energy) on TE index levels. The effort of each country for a better energy composition is taken into consideration for the determination of the efficiency index. This effort is recorded through the progress of the indexes in each year. When a country with very high levels of fossil fuel consumption shows higher development levels of both GDP and the index of non-fossil fuels, compared to the development levels of the index of fossil fuels, then, this country may be more efficient than the case of a country where, even if it shows lower levels of fossil fuel consumption, the development level of this index (index of fossil fuel consumption) far exceeds the development level of the GDP. This implies the lower ability of this country to effectively get a higher GDP for certain levels of total energy input. The countries using nuclear energy with the highest efficiency levels are often those with the lowest per capita consumption of nuclear energy. In some cases, the combination of fossil fuels and non-fossil fuels determines the level of efficiency. The countries which invest mainly in renewable energy resources and less in nuclear energy ensure the comparative advantage of energy saving and energy conservation. Through the application of the most appropriate energy mix (through the substitution of fossil fuels with non-fossil fuels), higher levels of energy efficiency can be achieved.