基于可能性与可用性的CCHP系统热力学分析

介绍了理想冷热电三联供(CCHP)系统的热力学原理，指出其巨大的节能潜力。通过与热电冷分产系统比较，分析了一种以燃气动力装置驱动的CCHP系统的经济性。讨论了CCHP系统的可能性与可用性。     

基于热气机分布式冷热电三联供效益分析

以上海地区一幢典型五层住宅建筑热、电、冷负荷需求为计算基础,分别计算了基于热气机的冷热电三联供系统和传统冷热电分供系统的一次能耗率、全年净收益以及投资回收期,验证了三联供系统的节能性和经济性。分析表明热气机余热利用率和能源价格是影响该三联供系统节能效益和经济效益的主要因素。     

冷热电联供系统能耗与CO2排放特性分析

建立了微型燃气轮机冷热电联供系统数学优化模型。基于上海某办公楼典型日负荷结构,以总运行费用最低为优化目标,采用模式搜索法对数学优化模型进行求解计算,分析了微型燃气轮机发电效率及空燃比对联供系统能耗与CO2排放特性的影响。研究结果表明微型燃气轮机发电效率及空燃比对联供系统能耗与CO2排放的影响趋势是一致的,可以通过调节微型燃气轮机发电效率及空燃比来充分发挥联供系统节能性和环保性的优势。     

燃气内燃机与燃气轮机冷热电联产系统的比较

介绍了美国建筑燃气内燃机与燃气轮机冷热电联产系统的应用现状。从变工况下的热电效率和火用效率两个方面比较了MW级燃气内燃机和燃气轮机冷热电联产系统的技术性能,分析了两者在不同冷热电需求下的一次能耗。对1～3MW建筑冷热电联产系统,燃气内燃机具有明显的节能和经济效益,而燃气轮机联合循环适用于规模更大的系统。     

热电冷联产系统节能性的(火用)分析

利用分析的方法,定义了等效发电效率,对常用热电冷联产系统形式的节能性进行了分析。认为相对于全国平均供电煤耗而言,热电冷联产系统的节能是有条件的,应选取合理的方式,优化设计和运行方案;相对于当前有些热电厂夏季负荷不足的情况,热电冷联产是节能的,在不同的情况下节能率在7.8%~39%之间。建议利用现有的热电联产条件,发展热电冷联产系统,提高现有热电厂的设备利用率和运行经济性。     

北京南站冷热电三联供系统探讨

介绍了北京南站冷热电三联供系统设计,包括方案选择、负荷计算、系统配置、运行策略、节能分析等。认为使用燃气内燃机比燃气轮机更具优势,建议在电力并网前提下采用以电定热原则确定系统设备容量配置。     

浅谈分布式区域冷热电联供系统

建筑节能已成为我国节能技术领域的重要议题。冷热电三联供技术是充分利用低品位热能的一种有效手段,该系统能源综合利用率高,一般均可达到70%以上。本文阐述了分布式区域冷热电联供系统的原理和特点,提出一种基于热气机的天然气能源岛系统。并指出充分推动分布式区域冷热电联供技术的应用,对于能源节约、环境保护、能源安全以及资本有效运作具有十分重要的意义。     

Evaluation of a turbine driven CCHP system for large office buildings under different operating strategies

Combined cooling, heating, and power (CCHP) systems use waste heat from on-site electricity generation to meet the thermal demand of the facility. This paper models a CCHP system for a large office building and examines its primary energy consumption (PEC), operational costs, and carbon dioxide emissions (CDE) with respect to a reference building using conventional technologies. The prime mover used in this investigation is a load share turbine, and the CCHP system is evaluated under three different operation strategies: following the electric demand of the facility, following the thermal demand of the facility, and following a seasonal strategy. For the various strategies, the percentages of total carbon dioxide emissions by source are presented. This paper explores the use of carbon credits to show how the reduction in carbon dioxide emissions that is possible from the CCHP system could translate into economic benefits. In addition, the capital costs available for the CCHP system are determined using the simple payback period. Results indicate that for the evaluated office building located in Chicago the CCHP operation reduces the operational cost, PEC, and CDE from the reference building by an average of 2.6%, 12.1%, and 40.6%, respectively, for all the different operational strategies.     

天然气型冷热电联供系统应用分析

阐述了天然气驱动的冷热电联供(CCHP)系统的形式和特点,比较分析了使用天然气的冷热电联供系统与常规冷热电分供系统的一次能源利用率,指出联供系统可提高能源利用率,节约一次能源20％～30％。燃气内燃机型冷热电联供系统的回收期比燃气轮机型冷热电联供系统的回收期短,但能源利用率较低。文章从经济性角度 (回收期)分析了天然气和电力价格对冷热电联供系统推广应用的影响。     

热电冷联产系统节能效益分析

分别以热电冷联产系统的燃料节约量、当量热力系数及热电冷联产系统的供电煤耗作为评价标准,对热电冷联产系统的节能效益进行了分析与研究,并提出了临界供电煤耗概念,作为判断在热电冷联产系统中节能的条件。     

Analysis and optimization of CCHP systems based on energy, economical, and environmental considerations

Analysis of combined cooling, heating, and power (CCHP) systems is frequently based on reduction of operating cost without measuring the actual energy use and emissions reduction. CCHP systems can be optimized based on different optimization criterion such as: energy savings, operation cost reduction or minimum environmental impact. In this study, CCHP systems operated following the electric load (FEL) and the thermal load (FTL) strategies are evaluated and optimized based on: primary energy consumption (PEC), operation cost, and carbon dioxide emissions (CDE). This study also includes the analysis and evaluation of an optimized operational strategy in which a CCHP system follows a hybrid electric-thermal load (HETS) during its operation. Results show that CCHP systems operating using any of the optimization criteria have better performance than CCHP systems operating without any optimization criteria. For the evaluated city, the optimum PEC and cost reduction are 7.5% and 4.4%, respectively, for CCHP-FTL, while the optimum CDE reduction is 14.8% for CCHP-FEL. Results also show that the HETS is a good alternative for CCHP systems operation since it gives good reduction of PEC, cost, and CDE. This optimized operation strategy provides a good balance among all the variables considered in this paper.     

燃气轮机冷热电联供系统优化与节能经济性研究

以满足冷、热、电负荷需求时能源运行成本最低为优化目标,建立了联供系统经济最优化模型。结合实际应用场合负荷需求验证了联供系统的节能性和经济性。指出联供系统最优化运行模式与电气价格比有关,当电气价格比较低时,分供系统运行更经济。分析了各性能参数对系统经济性的影响,结果表明燃气轮机发电效率、吸收式制冷机的制冷系数及烟气余热回收效率对联供系统的经济性影响较大。     

Energy efficiency and economic feasibility analysis of cogeneration system driven by gas engine

A cogeneration system driven by gas engine is proposed and studied. The cogeneration system can provide electricity generation and cooling/heating for buildings. The cogeneration system has a large potential for energy saving and economical benefits. Primary energy rate (PER) and comparative primary energy saving are used to evaluate and compare the performances of the cogeneration system and conventional separate system. The comparative primary energy saving of the cogeneration system is more than 37% compared to conventional separate system at the required energy flows. The total annual income, the total annual saving and payback period of the cogeneration system are used to analyze its economy. The calculation result of economic analysis shows that the cogeneration system has a good economic benefits.     

初探冷热电三联供系统在A级数据中心的应用

冷热电三联供(CCHP)系统是一种建立在能量梯级利用概念基础上,将供热(采暖和供热水)、制冷及发电过程有机结合在一起的总能系统。本文按照数据中心的用能特点,探讨了三联供系统在数据中心中应用的可行性。     

热电冷联产与分产能耗比较分析

将热电冷联产与分产能耗比较分解为供热、供电、供冷三种煤耗差进行分析，建立了以分产为基准的三种煤耗差计算公式，探讨了煤耗差随热、冷负荷的变化情况，给出了目前一般情况下联产的节能条件、判据及措施。     

三联供系统的研究

冷热电三联供系统作为分布式能源的一种，具有高能效、低排放等诸多特点，随着其技术的日渐成熟，该技术也越来越多地受到业主的关注。本文意在通过介绍三联供系统的意义、特点、系统型式等方面内容，并对这种新能源利用进行探讨，为设计和研究应用该系统的人员提供方向。     

冷热电联供系统成本分摊法研究

根据以微型燃气轮机为动力源的冷热电联供系统的工作流程,建立了其热力学模型.通过对其能量利用过程的分析,引入可用(火用)和折合炯的概念.在综合考虑冷热电联供系统中制冷量和供热量占系统总可用能比例的基础上,建立了以折合(火用)概念为基础的冷热电分摊模型.该模型克服了现有其他方法存在的缺陷,较其他方法更合理、实用.     

天然气三联供技术在城市综合体中应用分析

天然气冷-热-电三联供技术是一种建立在能源梯级利用基础上,制冷、供热和发电过程一体化综合应用的多联产系统。在城市综合体项目中应用天然气冷-热-电三联供技术,不但通过发电自用减缓城市供电压力,还能够充分利用余热资源为建筑提供采暖、制冷和生活热水,减少常规能源的消耗,具有良好的经济、环境和社会效益。在能源环境危机日益突出的当代社会,天然气三联供技术将会得到广泛的应用。     

数据中心冷热电联供系统全工况热力性能分析

建立了夏热冬冷地区某数据中心天然气冷热电联供系统全工况数学模型。得到了燃气轮机和双效溴化锂机组的全工况性能规律,计算了系统夏季典型日冷热电输出及一次能源利用率、相对节能率,并比较了设备容量配置对系统性能的影响。结果表明,数据中心总冷负荷相对常规建筑较大,联供系统夏季典型日的热力性能总体较高。在研究范围内,增大溴冷机组容量或减小电制冷机组容量,有利于提高系统的总体一次能源利用率和相对节能率。本研究为数据中心冷热电联供系统的设计和运行优化提供依据。     

Real heat recovery with air handling units

More and more air handling units are equipped with heat recovery systems, with the aim of decreasing the energy use in buildings for heating and cooling. The efficiency of the heat recovery system is often used to calculate the energy saving. However, air-handling units do not always function as planned. In particular, parasitic shortcuts and leakage may decrease dramatically the efficiency of ventilation and heat recovery. In addition, these units need electrical energy for fans, which may be more precious than saved heat. Measurements, using tracer gas dilution technique have detected various malfunctions in several units.This paper addresses real energy recovery with air handling units from a theoretical point of view and presents results of measurements on 13 units. In the best three cases, the real, global heat recovery efficiency was between 60 and 70% for units having a 80% nominal efficiency. In the three worst cases, the global efficiency was less than 10%. For these cases, the heat recovery system uses more energy than it saves.