Study on Energy and Environmental Efficiency for Coal-fired Power Units: A Non-parameter Approach

The analysis of the economic efficiency of agriculture has been the subject of numerous studies. An economically efficient agricultural sector is not always environmentally efficient. Agriculture is a large emitter of greenhouse gases. The Intergovernmental Panel on Climate Change states that food production and agriculture are responsible for 21–37% of total global CO2 emissions. Due to the comprehensive assessment of the agricultural efficiency, it is worthwhile to apply to its measurement an integrated approach based on economic, energy and environmental aspects. These aspects were the main reasons for undertaking this research. The purpose of the study was to determine the economic, energy and environmental efficiency of agriculture in the EU Member States in 2019. The environmental analyses relate to the period 1990–2019. A total of 26 member states of the European Union (excluding Malta and Luxembourg) were selected for research. The sources of materials were Eurostat and the European Environmental Agency. This study was based on the Data Envelopment Analysis method, and used the DEA model focused on minimizing inputs. The research also adopts energy productivity and greenhouse gas emission efficiency indicators. The DEA model features the following variables: one effect (value of agricultural production) and four inputs (land, labour, use of fertilizers and use of energy). It was found that seven out of the 26 studied EU countries have efficient agriculture. The efficient agriculture group included The Netherlands, Denmark, Greece, Cyprus, the United Kingdom, Italy and Ireland. Based on the DEA method, benchmarks have been defined for countries with inefficient agriculture. On the basis of these benchmarks for inefficient agricultural sectors, it was possible to determine how they could improve efficiency to achieve the same results with fewer inputs. This issue is particularly important in the context of sustainable agricultural development. In the next stage of the research, the analysis of economic and energy efficiency was combined with the analysis of GHG emission efficiency in agriculture. Four groups of countries have been distinguished: eco-efficiency leaders, eco-efficiency followers, environmental slackers, eco-efficiency laggards. The leaders of the classification were The Netherlands, Italy, Greece, Cyprus and Portugal.

Dynamic and network slack-based measure analysis of China’s regional energy and air pollution reduction efficiencies

Study of energy strategy by evaluating energy–environmental​ efficiency

Energy and environmental efficiency evaluation based on a novel data envelopment analysis: An application in petrochemical industries

Energy, environmental, and economic efficiency in fossil fuel exporting countries: A modified data envelopment analysis approach

Prior to Mexico's entry to the North American Free Trade Agreement (NAFTA), predictions of the consequent impact on the environment in that country ranged from the dire to very optimistic. This article investigates NAFTA's outcomes in terms of energy use and the emission of atmospheric pollutants. Specifically, has entry into NAFTA led to a convergence or divergence in indicators of emissions, environmental efficiency, and emissions‐specific technology in Mexico, the United States, and Canada? A battery of tests is applied to these indicators for energy use and carbon, sulfur, and NOx emissions in the three countries. The results show that the extreme predictions of the outcomes of NAFTA have not materialized. Rather, trends that were already present before the introduction of NAFTA continue and, in some cases, improve post‐NAFTA, but not yet in a dramatic way. There is strong evidence of convergence across the three countries toward a lower intensity of energy use and emissions per unit of GDP. Although intensity is rising initially for some variables in Mexico, it eventually begins to fall post‐NAFTA. Per capita emissions of sulfur and NOx also show convergence, but this is not the case for energy and carbon, and the latter variables also drift moderately upwards. The state of technology in energy efficiency and sulfur abatement is improving in all countries, although there is little, if any, sign of convergence and NAFTA has no effect on the rate of technology diffusion. However, total energy use and carbon emissions increase both pre‐ and post‐NAFTA and total NOx emissions increase in Mexico. Only total sulfur emissions are stable and falling in all three NAFTA partners.

According to the characteristics of mechanical equipment remanufacturing system, the dynamic performance of energy consumption and emission is explored, the equipment energy efficiency and emission analysis model is established firstly, and then energy and ecological efficiency analysis method of the remanufacturing system is put forward, at last, the energy and ecological efficiency of WD615.87 automotive diesel engine remanufacturing system as an example is analyzed, the way of energy efficiency improvementnt and environmental friendly mechanism of remanufacturing process is put forward.

The article is devoted to consideration of issues related to assessing the energy efficiency of a coal mining enterprise. Coal mining enterprises are characterized by a large volume of energy intensive ore mining operations. The article presents possible ways of energy saving in the mining industry. During the research, a system of energy efficiency indicators for coal mining enterprises is presented. Materials and methods. The article proposes a system of indicators for coal enterprises based on existing methods and approaches to assessing energy efficiency. Energy consumption dependence graphs, benchmarking, and pinch analysis are considered as a starting point. Results. The study presents a system of energy efficiency indicators for coal mining enterprises. The proposed system has several levels. The existing methods and approaches for assessing this important indicator for industrial enterprises in the coal industry as a whole are considered. The author’s approach to formalizing the system of energy efficiency indicators for coal mining enterprises is proposed. The significance of energy audit as a key assessment measure is indicated and its stages are highlighted. The influencing factors determining energy costs and their reduction for a coal mining enterprise are systematized, barriers preventing the practical implementation of energy saving measures are analyzed. Discussion. The proposed metrics system provides a comprehensive framework for assessing the energy efficiency of coal mining enterprises at various levels. Its flexibility allows it to be applied to the analysis of individual equipment units, production processes, and overall enterprise performance. Its multi-level approach provides a detailed understanding of energy consumption, which allows for informed decision-making to optimize operations. At the equipment level, the metrics system evaluates the energy consumption and efficiency of individual machines and devices. At the production process level, the metrics system analyzes the energy consumption and efficiency of various stages of coal mining. At the enterprise level, the metrics system provides a comprehensive assessment of overall energy efficiency. It takes into account energy consumption at all levels and allows enterprises to compare their performance with each other and with industry benchmarks. Conclusion. Energy efficiency assessment of a coal mining enterprise allows to understand how and where energy is used, where its use can be improved, and how to reduce its costs. To conduct an energy efficiency assessment, the article proposes a system of indicators, highlighting the features of an energy audit. The main advantage of the proposed system of indicators is that it covers a wide range of energy consumption indicators, which are carefully selected and located at different levels of detail. In general, a balanced approach to the level of detail and generalization in the system of indicators provides flexibility in adapting indicators to specific research questions and helps to interpret the results in the context of structural differences between energy systems. Resume. Overall, the proposed metrics system offers a comprehensive approach to analyzing the energy efficiency of coal mining enterprises, covering all levels of operations. Its use allows enterprises to improve energy efficiency, reduce operating costs, and contribute to a more sustainable coal mining industry. Suggestions for practical applications and directions for future research. The use and implementation of the developed system at a coal mining company allows it to improve energy efficiency, reduce operating costs and contribute to a more sustainable coal mining industry.

The rapid economy expansion in China has substantially increased energy consumption. Under the stringent environmental policy and the requirement of green economy development, the accurate assessment and analysis of energy efficiency is an increasingly significant issue for energy development policy making in China. This study uses the weighted slacks-based model (weighted SBM) considering the energy substitutability to evaluate the regional energy efficiency (EE) in 29 Chinese provinces, from 1991 to 2015, and explores the sustainable evolution characteristics of EE by comparative and convergence analyses from different perspectives. The empirical results show that EE has significant geographic differences. On the one hand, EE increases from the west to the east of China, and its volatility has a rising trend over the period 1991–2015. Only the EE in the eastern area had a stable rising trend, and the EE differences are difficult to reduce in the short term. On the other hand, the economic zones in the south of China, such as Central Bohai, Pearl River Delta, and Yangtze River Delta, have higher EE. We also find a significant EE improvement occurred during the Eleventh and the Twelfth Five-Year plans. By means of the convergence analysis of energy efficiency across different areas and economic zones over different time intervals, it is shown that EE in the southeast coast provinces have a better catching-up effect and adjustment rate toward the efficient frontier, while the western inland provinces are less effective over the period 1991–2005. Further, we empirically find that the industry policies including industry transfer policy promote EE globally, but the regional differences and fluctuations in EE remain serious. Certain policy implications are discussed with regard to sustainable regional development and an effective industry transfer policy.

Recent Developments and Future Directions at Energy Policy

Emissions from vessels are a major environmental concern because of their impacts on the deterioration of the environment, especially global warming of the atmosphere. Therefore, the International Maritime Organization (IMO) concerns significant care to environmental protection through the reduction of exhaust emission and improvement of energy efficiency through technical and operational measures. Among the suggested measures from IMO, the alternative fuel such as natural gas has the priority to be used instead of fossil fuels. The present paper calculates the effect of using natural gas in a dual-fuel engine from environmental and energy efficiency perspectives. As a case study, a container ship has been investigated. The results of the analysis show that the percent of CO2, NOx, and SOx emission reduction corresponding to using a dual-fuel engine operated by natural gas instead of a diesel engine operated by heavy fuel oil is about 30.4%, 85.3%, and 97%, respectively. Moreover, it found that NOx and SOx emission rates of the dual-fuel engine comply with the IMO 2016 and 2020 limits, respectively. Furthermore, the Energy Efficiency Design Index value in the case of using dual-fuel engine is lower than the value by using diesel engine by about 30%, and this value will be 77.18%, 86.84%, and 99.27% of the required value for the first, second, and third phases, respectively, as recommended by IMO.

Highlights on energy efficiency improvements: a case of a small brewery

Energy efficiency analysis has focused predominantly on reducing energy at its point of use by individual components, processes, or products. Efforts to address the energy embodied in materials through strategies and technologies that reduce raw material production - while maintaining the function and use of materials - offer a complementary and expansive approach to traditional energy efficiency analysis. The U.S. Department of Energy (DOE) energy analysis community currently lacks analytical tools that are appropriate for 1) estimating on a product and economy-wide basis energy efficiency potential achieved through material efficiency strategies and 2) evaluating how these new strategies may complement existing energy efficiency efforts. The goal of this report is to describe a standardized analysis framework that would enable calculation of embodied and direct energy and the estimation of energy reduction potential achieved through changes in material use. The proposed framework meets this functionality by spanning the entire U.S. economy, including international trade flows; capturing material and energy use in products and services from raw material extraction to retirement; maintaining material and energy balances; and adjusting dynamically to absolute and relative changes in materials and energy use. The framework is composed of two main elements: a dynamic hybrid input-output (IO) model and a material energy identity. The hybrid IO model defines recipes for material and energy flows in physical (e.g., British thermal units [Btus] and tons) and monetary units, and allows for dynamic adjustments to the amount of materials and energy used. The second element of the analytical framework, the material energy identity, acts as a way of identifying and organizing energy and material efficiency strategies, which are then implemented and analyzed in the hybrid IO model. The report also provides a simple example application of the proposed framework, which illustrates the concept of reducing energy use through changes to material efficiency.

China has made huge economic achievements based on industry. Heterogeneity, resulting from the industrial structure, energy endowment, and infrastructure among regions, has always been neglected on industrial performance evaluation. This paper focuses on provincial industrial heterogeneity to make a study. Firstly, meta-frontier slack-based measure is employed to rate industrial energy and environment efficiency of China. Besides, spatial evolution characteristics of efficiencies are described by global Moran's I and local Moran's I index. Taking the spatial correlation effect of efficiency into consideration, factors driving Chinese industrial energy and environment efficiency are analyzed and distinguished by quantitative regression and spatial Durbin model. It finds that (1) technical inefficiency and managerial inefficiency mainly attribute to the inefficiency of industrial energy and environment. (2) Chinese industrial energy and environment efficiency presents a stable spatial agglomeration as "high aggregation, low aggregation." It is necessary and indispensable for provinces and regions to cooperate to enhance efficiency. (3) Each province has a distinct driving mechanism of efficiency. The improvement policy of efficiency should be diversified for different provinces.

Overview of hygienization pretreatment for pasteurization and methane potential enhancement of biowaste: Challenges, state of the art and alternative technologies