**1. Introduction**

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192 New Developments in Renewable Energy

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With the rapid development of the global economy, more people are living in urban than rural areas, thereby contributing to a significant increase in demand for energy, especially in emerging countries [1] [2] [3] [4]. The realization that fossil fuel resources required for ener‐ gy generation are becoming scarce and that climate change is related to carbon emissions in‐ to the atmosphere has increased interest in energy conservation and environmental protection [5].

Among other recent issues, climate change, energy demand and fluctuations in international oil prices have become the focus of global attention. Renewable energy sources are now the fastest-growing sector of the energy mix and offer significant potential to address issues of energy security and sustainability [6]. All countries seeking to achieve the Kyoto Protocol target of reducing greenhouse gases, have renewable energy as the focus of their energy pol‐ icy, and some have even become the mainstream of energy development. The energy we currently use is subject to unrestricted exploitation, not only about to run out of the global stock of face time, energy conversion process produce tangible and intangible waste, that have a significant effect on the global environment. To ensure a stable energy supply, en‐ hance our energy supply security, reduce dependence on fossil fuels, and reduce green‐ house gas emissions, developing renewable energy sources has also become our current economic development and environmental resources for the biggest issue.

Thus, in face of the current trends, the demand for energy is rising. In addition to focusing on the power generation efficiency of power plants, we should also consider each unit of electricity efficiency to achieve an effective energy-saving effect in the pursuit of sustainable resource use. Therefore, we adopt a two-stage data envelopment analysis (DEA) [7] and in‐ corporate two sub-processes into a DEA efficiency model to evaluate the level of manage‐

ment performance within renewable energy in the OECD countries. We measure managerial efficiency in two phases: operating efficiency (OE) and the energy density efficiency (DE).

put and two output variables. Azadh, Ghaderi and Nasrollahi [15] measured the efficiency of wind power plants with the lowest possible costs using DEA, with data collected from 25 cities in Iran with 5 regions within each city using DEA with four input and two outputs.

Comparative Analysis of Endowments Effect Renewable Energy Efficiency Among OECD Countries

http://dx.doi.org/10.5772/52020

195

In this section, we propose several hypotheses. Considering Sahelian countries, energy ac‐ cess remained relatively low until recently, despite the abundance of renewable resources such as wind and solar energy. The abundance of renewable resources assumes that access to renewable technologies could increase and improve energy access in remote rural areas [16]. They are compatible with local conditions and resource endowment. Research on re‐ gional development specifically related to China's Western Development Program by the China Energy Strategic Research Group and Fan, Sun & Ren [17] discussed sustainable de‐ velopment issues for economically disadvantaged areas such as the ecological deterioration and sustainable livelihoods of rural households, and suggested reasonable approaches to address energy problems in these areas, such as the use of rich natural resources (endow‐ ment), development of renewable energy, and developing a moderate centralized energy supply that considers local energy endowment conditions. Shi [18] supported a similar type of energy development because a region's unique energy endowments reflect it is energy developmental differences. Chen and Zhu [19] specifically used resource endowment, zon‐ ing separation of wind power and solar power resources, the classification results for the preliminary study on China's energy and economic regionalization. Chen and Zhu argued that there is little evidence on whether the impact of economic development on the electrici‐ ty mix is affected by energy resource endowments [19]. Marcotullio and Schulz [20] provid‐ ed evidence of endowment's heterogeneity in energy mix transitions across countries.

British Petroleum discussed China and India's rapid increase in energy use because they represent approximately one-third of the global population, the expected depletion of oil re‐ sources in the near future, and the effect of human activities on global climate change. Bet‐ tencourt [2] indicated that as economies and populations continue to grow rapidly, energy and power consumption also increase at the same rate. The Empresa de Pesquisa Energética (EPE) indicated that because of population growth, urbanization and higher income, annual electricity consumption in the residential sector is growing steadily from 4.7% in 2003 up to 6.2% in 2009. The International Energy Agency (IEA) [6] and United Nations (UN) [4] stated that approximately 4.9 billion people (80 % of the global population) lived in developing countries as of 2001. The current annual population growth rate is approximately 1.5 % in developing countries. However, despite the lower living standards and lower per capita en‐ ergy use in developing countries, total energy use in developing countries is increasing fair‐ ly rapidly. Crane and Kinzig [4] indicated that many countries in the pursuit of economic development, the population increase rapidly as the same time, but also face a requirement to increase energy. There is a growing need to implement energy efficiency. Therefore, we

Therefore, we present the following hypotheses:

*H1a: Endowment and OE are positively causal related*

*H1b: Endowment and DE are positively causal related*

present the following hypotheses:

This method is different from those of previous studies that focused primarily on assessing OE [8] [9]. We divide the efficiency of energy plants into two components. Management per‐ formance is no longer constrained with production efficiency but constitutes a broader di‐ mension that covers operating activities and the efficiency of energy use. Compared to the traditional single-efficiency model, the sub-processes model is more suitable for evaluating the usage performance because of energy industry characteristics.

This evaluation model is useful for energy managers and current policy-makers. For manag‐ ers, it provides a more detailed performance evaluation process including two essential op‐ erational elements in the energy generation industry; for policy- makers, it offers a complete measurement of efficiency and is based on variable combinations of these two dimensions; policy-makers can identify the most suitable policy (e.g., a subsidy) and develop the most effective strategy.

Taiwan is an island, country that is extremely lacking in energy and is more than 98% de‐ pendent on imported energy. Taiwan is also influenced by political and geographical con‐ straints; therefore, the capacity to acquire energy is difficult compared to other countries. Thus, implementation of renewable energy and the abolition of nuclear power generation is a potential policy priority for Taiwan. Seeking the most cost-effective strategy, Taiwan's na‐ tional conditions, if we can use the experience of other countries, will become Taiwan's de‐ velopment of a great help. OECD countries including highly and lowly developed countries, especially developing countries, is from the energy consumption, low efficiency and serious pollution to the economic development mode shift to energy efficient, less polluting eco‐ nomic development mode. In this study, we discuss and compare 34 OECD countries' re‐ newable energy OE and DE by DEA. Finally, we present our conclusions and provide suggestions for renewable energy development in Taiwan. β
