ESTIMATION OF ENERGY REQUIREMENTS OF MORNING DEW EVAPORATION FROM LEAF SURFACES1

ABSTRACT: Evapotranspiration from vegetation is generally computed without consideration for early morning energy loss involved in drying wet leaf surfaces. In humid areas where dew formation is frequent, estimation of energy requirements for evaporating dew should be of interest. In this study, sensible heat flux (H) was computed from wind and temperature profile measurements over the study site. A leaf wetness sensor was used to measure the duration of evaporation from an exposed leaf surface, and net radiation was measured with a radiometer. The energy flux during the period of wet leaf surface evaporation was integrated over time. A cattail lysimeter situated at the site indicated the time when evapotranspiration started after wet leaves were dry. The energy requirements to dry an exposed wet leaf surface was estimated using energy balance methods. The mean value based on 44 days of observations from mid February to early May of 1993 indicates that the energy required to evaporate dew from openly exposed wet leaves was 5 percent of the total daily evapotranspiration of cattails with a coefficient of variation of 0.72. The mean time required to evaporate dew from exposed leaf surfaces from the onset of positive net radiation was 78 minutes. The mean dew evaporation in a morning from an exposed leaf surface was 0.16 mm with a maximum value of 0.41 mm. The energy required to dry wet leaves is a factor that should be considered when modeling evapotranspiration at hourly or shorter time intervals. Also, physical evapotranspiration models need to account for energy requirements for drying dew and rainfall wetted leaves.     

REGULATORY REQUIREMENTS AFFECTING AQUIFER THERMAL ENERGY STORAGE1

ABSTRACT: Thermal energy storage involves the capture and storage of thermal energy (either heat or chill) during one time period for use at a later period. Storage of thermal energy in aquifers on a seasonal basis is one promising application of the technology that has been implemented in several foreign countries and is currently undergoing field testing in the U.S. Potential developers of aquifer thermal energy storage projects will face a number of regulatory requirements at the federal, state, and local level of government. These can include meeting: (1) surface land and ground water use restrictions, (2) regulations relating to withdrawal of ground water, and (3) requirements for reinjecting thermally altered ground waters. Separate permits for ground water withdrawal and reinjection may be required. The permit process is likely to involve opportunities for public comment and may involve contested proceedings.     

我国能源开发面临的问题与对策

分析了我国能源开发的现状,指出现行能源结构给能源开发和消费带来的三个主要问题:能源开发利用程度低、环境污染严重、现行能源战略不能满足社会可持续发展的需要.在此基础上,提出了调整现行能源结构、发展洁净煤技术、加大我国西部天然气开发的投入、发展核能和加大可再生能源的开发利用等发展战略.     

Achieving energy security in South Asia

South Asia is experiencing unprecedented energy scarcity due to population growth, inadequate infrastructure, lack of investment, and other factors. However, energy security is one of the basic requirements of economic growth, and as its extension, for social harmony. This article identifies challenges to energy security in South Asia and proposes solutions on tackling the challenges.     

Practical Minimum Energy Requirements for Chemical Product Manufacturing: A Management Decision Tool for Achieving Sustainable Products

Practical Minimum Energy requirements comprise a management decision tool designed to assist companies in adopting strategies for more sustainable products through improved energy efficiency. This tool allows managers to gauge the potential for reducing the energy intensity of chemical processes as well as the environmental impacts associated with energy consumption, such as greenhouse gas emissions. © 2001 John Wiley & Sons, Inc.     

Applying exergy analysis to rainwater harvesting systems to assess resource efficiency

In our continued effort in reducing resource consumption, greener technologies such as rainwater harvesting could be very useful in diminishing our dependence on desalinated or treated water and the associated energy requirements. This paper applies exergy analysis and exergetic efficiency to evaluate the performance of eight different scenarios of urban rainwater harvesting systems in the Mediterranean-climate Metropolitan Area of Barcelona where water is a scarce resource. A life cycle approach is taken, where the production, use, and end-of-life stages of these rainwater harvesting systems are quantified in terms of energy and material requirements in order to produce 1 m³ of rainwater per year for laundry purposes. The results show that the highest exergy input is associated with the energy uses, namely the transport of the materials to construct the rainwater harvesting systems. The scenario with the highest exergetic efficiency considers a 24 household building with a 21 m³ rainwater storage tank installed below roof. Exergy requirements could be minimized by material substitution, minimizing weight or distance traveled.     

风电场水土流失防治法律制度的失灵与矫正

可再生能源的法制保障和法治水平关系其持续健康发展。风力发电（以下简称风电）虽然提供了可再生能源,但在建设时期容易造成水土流失、植被破坏等生态环境影响。《中华人民共和国可再生能源法》宣示了保护环境的立法目的,但缺乏配套的法律制度。《中华人民共和国能源法（征求意见稿）》侧重能源开发利用,但缺乏环境规制治理保障能源安全的法律制度。《中华人民共和国水土保持法》颁布实施的时间较早,防治水土流失的相关法律制度已不适应风能的开发利用。本文通过典型案例,发现风电场环境治理存在环境影响评价制度治理低效化、水土保持设施“三同时”制度法律监管不足、水土保持与环境影响评价“并联审批”设计缺陷等法律制度失灵症状,大量水土流失造成的生态环境损害尚未得到法律救济,为此提出了防治水土流失的法律矫正措施。     

Immersion frying for the thermal drying of sewage sludge: an economic assessment

This paper presents an economic study of a novel thermal fry-drying technology which transforms sewage sludge and recycled cooking oil (RCO) into a solid fuel. The process is shown to have significant potential advantage in terms of capital costs (by factors of several times) and comparable operating costs. Three potential variants of the process have been simulated and costed in terms of both capital and operating requirements for a commercial scale of operation. The differences are in the energy recovery systems, which include a simple condensation of the evaporated water and two different heat pump configurations. Simple condensation provides the simplest process, but the energy efficiency gain of an open heat pump offset this, making it economically somewhat more attractive. In terms of operating costs, current sludge dryers are dominated by maintenance and energy requirements, while for fry-drying these are comparatively small. Fry-drying running costs are dominated by provision of makeup waste oil. Cost reduction could focus on cheaper waste oil, e.g. from grease trap waste.     

WATER CONSTRAINTS ON EMERGING ENERGY PRODUCTION1

ABSTRACT: A comprehensive nationwide recognizance-level assessment of water needs for energy development over the 1985 to 2000 time frame and options for overcoming any actual or potential water supply problems are summarized. Water requirements for energy production and other uses are totaled for each geographic region of the United States and compared with available stream flow to identify regions with potentially inadequate water supplies to meet expanding energy needs. Water quality impacts and water-related institutional factors affecting energy development are also considered. It is concluded that, if proper planning measures are not initiated, water demands for energy production will not be satisfied by the year 2000, particularly in those areas with known fossil energy resources. No unmanageable water quality problems are foreseen, and water-related institutional factors will primarily delay rather than exclud energy development.     

WELMM, A SYSTEMS APPROACH TO ENERGY RESOURCES

In assessing energy resources it is interesting to consider their systems aspects and interrelationships with other natural and/or human resources. This is the purpose of the WELMM approach (Water, Energy, Land, Materials, Manpower) which analyzes resources requirements through the use of various Data Bases. Present applications focus on the comparison of various energy options and assessment of various long term strategies. The method can also be used for Integrated Resources Management.     

Potential use of oil shale for direct production of power in Jordan

Up until the present, Jordan has relied almost exclusively on imported petroleum for its primary energy requirements. Encouraged by emerging technologies and recent fossil fuel discoveries, Jordanians are seriously examining exploitation of their own indigenous energy resources to meet projected mid- and long-term power requirements. The most prominent of the known resources is oil shale. This report addresses the oil shale-for-power-production option in Jordan. Under consideration are 20 MW and 50 MW demonstration units and a 400 MW commercial-scale plant. The report focuses on three areas: (i) the engineering feasibility of using Jordan's oil shale in a circulating fluidized bed combustion (CFBC) boiler; (ii) environmental aspects of the proposed oil shale-for-power plants(s); and (iii) the economic feasibility of the proposed plant(s). The results could be useful for other low- to middle-income countries considering oil shale as an option for power production.     

袋式除尘技术的应用及发展

论述了袋式除尘技术在节能减排中的作用;介绍了我国袋式除尘技术目前的应用水平及存在的问题;提出了袋式除尘技术和产业的发展方向。     

电驱动道路车辆动力锂离子电池组和电池系统性能试验条件和要求

本文是电驱动道路车辆动力锂离子电池的试验和要求标题下的电池组和电池系统性能试验部分。结合国标转化过程和实验室能力验证经历,在能量、容量、功率、内阻、能效和损耗等性能试验方法和要求作了具体的描述和解释。供实验室和相关产品的供需方双参考。     

CQC 3114-2015标准与CQC 3114-2009标准的主要差异

面对计算机行业的飞速发展,产品生产企业在不断创新技术的同时,也需要持续了解国家对产品节能认证及测试的最新标准,已满足产品节能的新要求。本文简述新旧版计算机节能认证技术规范的主要差异,运用实例比对阐述标准的使用,帮助企业更好的理解新版标准的实施。     

Energy use in Denmark

This paper reviews the evolution of energy use in Denmark since the early 1970s, in order to shed light on the future path of energy use in Denmark, with particular emphasis on the role of energy efficiency. Improvements in end-use energy efficiency reduced primary energy requirements in Denmark by 22% between 1972 and 1988. This change accounts for two-thirds of the decline in the ratio of energy use to gross domestic product that occurred during this time: the rest of the decline was caused by changes in the mix of goods and services produced and consumed by the Danes. Total energy savings achieved between 1972 and 1988 in Denmark ranked among the highest measured in any major OECD country. Overall, most of the energy savings in Denmark were brought about through improvements in technology. Short-term changes in consumer behaviour were significant in reducing energy needs for space heating and transport. An important stimulus for improved efficiency was higher energy prices, led in no small part by significant taxes imposed on small consumers of heating oil, electricity and motor fuels.     

Feeding fossil fuels to the soil: An analysis of energy embedded and technological learning in the fertilizer industry

In this paper, we assess energy demand due to fertilizer consumption in the period 1961–2001. Based on historical trends of gross energy requirements, we calculated that in 2001, global energy embedded in fertilizer consumption amounted to 3660 PJ, which represents about 1% of the global energy demand. Total energy demand has increased at an average rate of 3.8% p.a. Drivers behind the trend are rising fertilizer consumption and a shift towards more energy intensive fertilizers. Our results show that despite significant energy efficiency improvements in fertilizer manufacture (with exception of phosphate fertilizer in the last 20 years) improvements in energy efficiency have not been sufficient to offset growing energy demand due to rising fertilizer consumption. Furthermore, we found that specific energy consumption of ammonia and urea developed in close concordance with the learning curve model, showing progress ratios of 71% for ammonia production and 88% for urea. This suggests an alternative approach for including technological change in energy intensive industries in middle and long-term models dealing with energy consumption and CO₂ emissions, while few learning curves exist for energy efficiency of end use technologies.     

Quantitative evaluation of the chilled-ammonia process for CO2 capture using thermodynamic analysis and process simulation

There is strong world-wide interest in developing new and improved processes for post-combustion capture of CO₂, often using chemical absorption. Developers of new processes make positive claims for their proposals in terms of low energy consumption, but these are usually difficult to validate. This paper demonstrates that rigorous application of thermodynamic analysis and process simulation provides a powerful way to quantitatively estimate the energy requirements of CO₂-capture processes by applying the methodology to the analysis and evaluation of the chilled-ammonia process.     

WATER AND ENERGY IN THE WESTERN COAL LANDS1

ABSTRACT: Problems of water quality and quantity are critical to development of the energy resources of the Western U. S. Based on a number of independent measures, the Upper Colorado River Basin will experience severe water availability problems in a few decades if projected energy and agricultural development occurs. Given the impending collision between the competing interests of various Western water users, water resource management and conservation deserves the utmost attention. Substantial opportunities for conservation exist in energy and agricultural development. Selection of both conversion and cooling technologies and careful siting decisions can sharply reduce the water requirements of energy development. Agricultural water conservation strategies include improving irrigation and cultivation practices, removing phreatophytes, removing marginal lands from production, and changing crop patterns. In order to accomplish significant conservation, however, there must be changes in those aspects of Western water law that remove conservation incentives from the water use system.     

An interval type-2 fuzzy stochastic approach for regional-scale electric power system under parameter uncertainty

In this study, an interval type-2 fuzzy stochastic linear programming method (IT2FSLP) is developed to support regional-scale electric power system (REM) planning. The IT2FSLP-REM model is based on an integration of interval type-2 fuzzy sets boundary programming and stochastic linear programming techniques enable it to have robust abilities to the deal with uncertainties expressed as type-2 fuzzy intervals and probabilistic distributions within a general optimization framework. Moreover, it can reflect dynamic decisions for energy supply and energy conversion processes, as well as provide capacity expansion options with multiple periods. The developed model is applied to a case of planning regional-scale energy and environmental systems to demonstrate its applicability. Based on a two-step solution algorithm, reasonable solutions have been obtained, which reflect tradeoffs among economic cost, environmental requirements, and energy-supply security. Thus, the lower and upper solutions of IT2FSLP-REM would then help energy authorities adjust or justify allocation patterns of regional energy resources and services.     

稠油热采系统综合能耗监测方法及评价

针对目前稠油热采系统节能措施和节能产品对某一环节单个节能产品的节能效果进行检测、评价的现状,提出了将稠油热采系统作为一个整体,采取组合节能措施及产品,给出了稠油热采系统的能耗监测流程、监测要求、程序与方法、数据分析评价方法等。形成了稠油热采系统综合能耗监测数据分析及效果评价方法。