基于能值理论的区域水资源复合系统生态经济评价

从水资源复合系统的功能与特点出发,提出了采用能值(Emergy)理论与方法对区域水资源复合系统进行生态经济评价的新思路。论述了能值理论与方法的基本原理,绘制了区域水资源复合系统的能值系统图,编制了系统的能值分析表,构建了区域水资源复合系统的能值指标体系,并以我国东南沿海某县域为例进行了应用研究。实例表明,基于能值理论的区域水资源复合系统生态经济评价方法具有可行性和应用前景。     

基于能值的煤炭矿区生态效率评价

生态效率评价的难点是如何对每类环境和资源代价所包括的子指标进行统一单位的定量化换算,能值研究方法以太阳能为共同的基础参照标准,突破不同质量的能量之间统一评价的难题,解决了生态效率评价中定量化换算问题。运用能值理论,构建了基于能值的矿区生态效率指标体系（EEEIS）,并对2000-2009年徐州矿区的复合生态系统进行了能值评估和生态效率指标的计算。结果表明徐州矿区2000-2009年：经济增长速度基本快于生态消耗的速度,从资源依赖性经济走向资源效率型经济,生态效率稳步提升,水资源、煤炭资源利用集约化发展;矿区经济增长健康程度处于不断进步的状态。     

基于能值水生态足迹模型的黄河流域水资源利用评价

为辨析黄河流域突出的水资源问题,科学分析流域水资源利用状况,将能值理论和水生态足迹法相结合,构建能值水生态足迹模型,计算和分析了黄河流域2011—2018年的能值水生态足迹、能值水生态承载力和水生态盈亏状况.结果表明:2011—2018年黄河流域能值水生态足迹呈平稳上升趋势,能值水生态承载力呈先下降后上升趋势,但历年能...     

木质成型颗粒的能量和能值分析

文章对一个年产万吨的木质成型颗粒生产系统的可持续性进行了评价。利用能量和能值方法进行分析的结果表明:木质成型颗粒的总能量需求为0.088 J/J,能对减少化石能源消耗发挥重要作用,其中能量投入从高到低依次为电力、运输燃料和厂房设备;成型颗粒的能值转换率为6.15E+04 sej/J,其中的能值投入从高到低依次为木屑原料、电力和劳务;成型颗粒的可持续性综合指标ESI为17.26,与作为参考的蔗渣生物油和沼气系统相比,具有良好的可持续性。     

基于能值的土壤源热泵空调系统的可持续性评价

土壤源热泵空调系统的可持续发展能力需要从经济、社会和环境效益几个方面作定量分析.本文以武汉某办公楼的暖通空调工程为例,将土壤源热泵和空气源热泵、风冷冷水机组+燃油锅炉等3种常用的冷热源方案进行了可持续发展能力的比较评价.结果表明,与风冷冷水机组+燃油锅炉系统和空气源热泵系统等2种系统相比,土壤源热泵系统的能值产出率并没有优势,经济竞争力较差,但它给环境的压力最小,其能值可持续指数较高,可维持较长时间内的可持续发展.     

Transition to renewable energy systems with hydrogen as an energy carrier

Unlike the present energy system based on fossil fuels, an energy system based on renewable energy sources with hydrogen and electricity as energy carriers would be sustainable. However, the renewable energy sources in general have less emergy than the fossil fuels, and their carriers have lower net emergy. Because of that they would not be able to support continuous economic growth, and would eventually result in some kind of a steady-state economy. An early transition to renewable energy sources may prove to be beneficial in the long term, i.e., it may result in a steady state at a higher level than in the case of a transition that starts later. Once the economy starts declining it will not be able to afford transition to a more expensive energy system, and transition would only accelerate the decline. Similarly, if a transition is too fast it may weaken and drain economy too much and may result in a lower steady state. If a transition is too slow, global economy may be weakened by the problems related to utilization of fossil fuels (such as global warming and its consequences) before transition is completed and the result again would be a lower steady state. Therefore, there must be an optimal transition rate; however, its determination would require very complex models and constant monitoring and adjustment of parameters.     

燃煤电厂节能调度能值分析方法

节能调度是我国电力行业节能减排的一项主要措施,单一的供电煤耗指标不能全面反映燃煤电厂的节能减排。选取燃煤电厂的供电煤耗、SO₂排放、NO_x排放、等效可用系数、网损、水资源消耗量作为节能调度指标,采用能值分析方法,进行综合指标排序从而确定优先调度顺序。通过计算数据比较,提出的评价方法能较合理地反映燃煤电厂的节能减排情况,为节能调度提供参考。     

铜工业发展循环经济的能值指标体系研究

近年来,中国铜消费量大幅度增长,铜资源较为短缺,铜工业生态经济系统遭到严重破坏,如何衡量和评价铜工业的经济与环境协调程度,成为学界和研究者普遍关注的问题。定量评价循环经济的发展水平是循环经济的一个基础理论课题。基于能值理论,运用能值分析方法,从能值流量来源、能值经济社会、资源综合利用、环境压力及综合指数5个方面构建铜工业循环经济发展的能值评价指标体系,为正确认识铜工业生态经济系统的重要性和铜工业战略决策的科学化提供借鉴。     

多联产系统的能值评估

为了扩展能值分析方法的应用范围,根据能值分析的基本思想,并以能量守恒和能值守恒为依据,提出了能反映多联产系统特点的能值评价指标,该能值评价指标将多联产系统的成本结构、排放影响和节约的资源置于同样重要位置考虑.以煤基燃料-电力多联产系统（甲醇-电力,氢-电力）为案例进行了能值分析.结果表明：该能值评价指标能全面度量多联产系统及其可持续性;多联产系统的连接模式、技术配置等因素均影响着多联产系统的可持续性;合适的燃料-电力比例的多联产系统的可持续性与单产系统相比有明显改善.图4表3参11     

The evolution of urban water systems: societal needs,institutional complexities,and resource costs

ABSTRACT

Urban water systems provide critical services to meet the supply, sanitation, and drainage needs of urban societies. Evolving needs have resulted in increasingly expansive infrastructure, raising questions about the sustainability of such large infrastructure investments. In this study, we demonstrate the historical interplay between growing urban water needs, the services developed to meet them, and their total resource cost. We hypothesize that needs evolve hierarchically, with predictable outcomes in the form of service progression. To test this hypothesis, we use a suite of metrics at the US national scale indicative of our proposed hierarchy levels. At the city scale, we assess the cost implications of this progression of services. We use the emergy framework to quantitatively reconstruct the historical resource requirements of supply, sanitation, and drainage services and show how evolving needs lead to mounting resource costs. Lastly, we discuss implications of continually increasing complexity for meeting future water needs.