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861.
European Union (EU) climate/energy targets and policies are poised for the first full climate policy cycle – from adoption and implementation of the policy package for 2020, to reform for 2030. A dynamic approach to the ways in which EU policies affect policy development is developed by applying theories of domestic implementation, policy feedback and integration. Implementation experiences in Poland – the ‘least climate ambitious’ EU member state – affected Polish preferences for reformed EU policies. Existing EU policies, their ‘fit’ with Poland’s energy interests and change in anticipation of future EU policies explain much of the variation in preferences. Second, policy feedback from Poland significantly affected the EU 2030 climate and energy framework. As yet, the EU has succeeded only partly in gathering momentum through a ‘snowball’ effect whereby positive policy feedback from implementation generates further steps.  相似文献   
862.
There is a growing ‘energy democracy’ (ED) movement which regards the transition to renewable energy as an opportunity for socio-economic transformation, as well as technological innovation. The literature on ED tends to associate greater democratic control of energy systems with increased community control over the means of energy generation and distribution. Nonetheless, this literature often assumes rather than demonstrates that the forms of governance it promotes are more democratic than the status quo. This analysis contributes to the emerging field of ED by assessing the complex and varied ways in which communities in Scotland practise energy governance. By focusing on three key governance processes (decision-making, accountability and dispute resolution), the importance of local contexts for the establishment and negotiation of democratic practices is demonstrated. This local specificity, however, also raises further questions regarding the universal applicability of the ED concept.  相似文献   
863.
Sustainability and sustainable development are prominent themes in international policy-making, corporate PR, news-media and academic scholarship. Its definitions are contested, however sustainability is associated with a three-pillar focus on economic development, environmental conservation and social justice, most recently espoused in the adoption of the UN Sustainable Development Goals in 2015. In spite of its common usage, there is little research about how sustainability is represented and refracted in public discourse in different national contexts. We examine British national press coverage of sustainability and sustainable development in 2015 in a cross-market sample of national newspapers. Our findings show that key international policy events and environmental and social justice frames are peripheral, while neoliberalism and neoliberal environmentalism vis-à-vis the promotion of technocratic solutions, corporate social responsibility and “sustainable” consumerism are the predominant frames through which the British news-media reports sustainability. This holds regardless of newspaper quality and ideological orientation.  相似文献   
864.
Global climate change and the implementation of energy technologies are among the most pressing issues facing society and the environment today. Related educational content spans the science disciplines. Through an analysis of introductory-level university textbooks from four major US publishers in Biology, Chemistry, and Physics, this study presents trends in terminology and content. As the defining terms, “global warming” and “climate change” are used nearly equally. However, the first location of a working definition for climate change appears earlier. Energy technologies, climate change, and related environmental issues are found, on average, on ≤4% of textbook pages, and variation is large among individual textbooks. Discipline-based trends exist, especially for the energy technologies presented. Addressed separately as a non-renewable, non-fossil fuel, nuclear energy is found on ≤1% of textbook pages and unfavorably represented. The discussion within these science disciplines has implications on introductory-level education, public perception of science, and informed citizenship.  相似文献   
865.
近年来,电动汽车因其在行驶过程中无任何尾气排放,被各国政府视为推动交通部门清洁、低碳发展的重要途径,主要发达国家纷纷推出了各自的电动汽车发展战略。但是,由于电力属于二次能源,其上游电力生产阶段的能源消费是否清洁将对电动汽车的减排效果产生重要影响。考虑到目前中国绝大部分电力源于煤炭,电动汽车是否真正有益于减排还有待进一步验证。目前一些专家和学者基于传统的过程生命周期评价方法对电动汽车的能源消费、温室气体排放做了一些研究,但研究结果差异较大。为了对电动汽车的减排效果进行更精确的研究,本文采用混合生命周期方法对电动汽车的能源消费、温室气体排放进行了计算。同时,在考虑电动汽车的燃料生命周期、车辆制造生命周期的基础上,将相关配套充电设施建设生命周期纳入到电动汽车的全生命周期系统边界内,以使对电动汽车全生命周期的研究结果更加完整、精确。研究结果显示,纯电动汽车并非是"零排放"的,在燃料周期,虽然纯电动汽车的单位里程能源消费强度较小,约为传统汽油车的94.6%,但以煤为主的高碳电力结构导致目前纯电动汽车燃料周期的单位里程温室气体排放强度约为传统汽油车的1.12倍;车辆周期内,纯电动汽车的能源消费和温室气体排放量也略高于传统汽油车;此外,配套充电设施的建设也将增加纯电动汽车全生命周期的能源消费和温室气体排放量。综合燃料、车辆及充电设备的全生命周期,在当前的电源结构及技术条件下,电动汽车虽然具有较高的能源效率和较好的石油替代效果,但其全生命周期内的煤炭消费较高,导致其温室气体排放量高于传统汽油车,在当前的情况下大规模发展电动汽车并不利于温室气体减排。  相似文献   
866.
为减少旅游业能源消耗,实现旅游低碳绿色发展,探讨如何提高旅游业能源效率,基于包含非期望产出的方向性距离函数,首先构建了适应旅游业的Biennial Malmquist-Luenberger(BML)效率指数,以中国30个省市2005~2013年旅游业为实证对象,测度了其能源效率,9 a来旅游业能源效率变化源泉可被分解为全要素生产率、资本对能源替代效应、劳动对能源替代效应、能源结构效应和产出结构效应5项影响因素。研究发现:(1)中国旅游业能源效率整体上处于较低水平,旅游业能源效率可以扩张提升的比例较大。(2)整体上全要素生产率、资本对能源替代效应、劳动对能源替代效应和能源结构效应的提升能促进旅游业能源效率提高。(3)近3 a来劳动和资本投入的能源替代效应对旅游业能源效率变化的作用超过了全要素生产率。(4)区域层面上,东部地区旅游业能源效率高于中西部地区,主要由地区间旅游业对资本投入使用和能源消耗结构的差异造成。(5)整个样本期间,中国17个省市旅游业能源效率呈现下降趋势,背后的因素各有不同,旅游业资本替代效应是湖北省、福建省和浙江省等多数省市旅游业能源效率下降的主要因素,全要素生产率是安徽省、海南省、贵州省和甘肃省旅游业能源效率下降的主要原因。因此,合理利用投入的资源要素对旅游业低能耗发展至关重要,尤其是要发挥好资本对能源的替代效应,高效的资本配置能极大提高旅游能源效率。  相似文献   
867.
Abstract

Water is a key resource for all life. Recent droughts have also exemplified the importance for manufacturers to understand their impact on water resources. While most manufacturers typically know the amount of water they use in their facilities, they have little knowledge about the indirect effects they have on water resources. In this paper, the indirect impact from the automakers’ electricity use and work force on water resources is examined. Water withdrawal and consumption from electricity use by hypothetical but representative facilities around the world is quantified and analysed. Water withdrawal by the workers is also quantified and analysed. The results indicate that the water withdrawal and consumption by the workforce and caused by the use of electricity is larger than the direct water use and consumption in the facilities themselves.  相似文献   
868.
Abstract

Machine tool, which is the basis energy consumed device in manufacturing system, its energy consumption model and energy efficiency evaluation are the prerequisites for energy saving in manufacturing. Considering the multi-energy-sources features,analysed the mathematical model of a CNC continuous generating grinding machine tool from the view of energy constitute. The energy sources of a CNC continuous generating grinding machine tool are classified into gear grinding system, grinding wheel dressing system and auxiliary system. Based on the power balance equations of energy flow, the energy flow system of a CNC continuous generating grinding machine tool is established. And then the energy consumption mathematical model of a CNC continuous generating grinding machine tool is set up by combining the power balance equations with the operating features of three kinds of energy sources. The case study shows that the proposed energy consumption model can provide fundamental support for energy consumption forecasting, energy efficiency analysis and energy-saving optimisation during the machine tool operation process.  相似文献   
869.
Abstract

Energy management in small to medium enterprises (SMEs) remains undeveloped due to competing priorities and a lack of specialist knowledge. However considerable savings can be demonstrated where companies take the time to investigate their energy use. Savings of over 20% can be achieved through changes to operational and behavioural practice. Additional benefits, such as improved production tracking and improved maintenance, can been seen which add to the value in undertaking an energy monitoring and targeting (M&T) plan. The method described involves the application of a series of ‘virtuous’ cycles of engagement and energy savings that can be applied from the highest factory level right down to a specific machine. The analysis of overall energy use from utility bills and the visualisation of typical machine power profiles aid in understanding the drivers of energy consumption and in engaging management in energy efficiency. The monitoring of specific machines in production highlights the significant consumption of electricity during non-productive times. The development of energy performance indicators is described for product variations which can be useful in tendering for business and selecting optimum production pathways. The approach is illustrated with data from a case study of a precision engineering SME based in Limerick, Ireland.  相似文献   
870.
The objective of this research is to investigate the reduction in fuel consumption and emission in spark ignition engine using blended bioethanol-gasoline and novel radiator-tube heater. Different percentages of ethanol – 0, 5, 10, 15, 20, 25 and 30% – are employed. The blended fuel is then pre-heated by sending it into a tube-heater-installed upper tank radiator which has different shape. The results show a significant reduction in fuel consumption and emission in engine. The best economical fuel consumption occurs in the tube-heater with a fin pipe of 10 mm space at 2.153 × 10?3 cc per cycle or 5.632%. However, the most economical fuel consumption occurs when 25% of bioethanol is added to fuel at 3.175?×?10?3 per cycle. This decreases fuel consumption by 8.306%. The highest decrease in fuel consumption occurs when fuel blended with 25% of bioethanol and tube-heater of 10 mm 6.236?×?10?3 cc per cycle or 16.313% is combined. In terms of emission reduction, the tube-heater with a space of 20 mm between fins (Tube 20) using a fuel mixture of 25% ethanol and 75% gasoline produced the lowest CO emissions.  相似文献   
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