基于TRNSYS的太阳能耦合燃料电池热电联产系统的模拟研究

文章建立了太阳能耦合燃料电池热电联产系统的TRNSYS模型。采用镇江地区的天气数据(太阳直射辐射强度和环境温度),模拟了该系统在各典型日的火用效率。得出热电联产系统的集热量、发电量及火用效率均随着太阳辐射强度的增强而提高的结论。基于此,将热电联产系统的生命周期成本设为优化目标,采用Hooke-Jeeves算法对关键运行参数进行优化。结果表明:当集热器面积为15 m²,单电池片数为60个,蓄热水箱容积为5 m²,太阳能电池板面积为5 m²时,可以获得最小的生命周期成本49.1万元,比常规模型降低11.7%;优化后的热电联产系统在典型日的火用效率为50%~57%,较常规热电联产系统提升50.0%~85.7%。     

溴化锂吸收式制冷在热电厂中的应用

通过分析从热电联产(CHP)向热电冷联产(BCH P)发展的趋势,以及在提高能源利用效率、减轻环境污染和温室效应方面的优势.从公司事业部安装的溴化锂吸收式空调系统的实践出发,分析在热电企业中,利用现有管网的优势,根据需要利用溴化锂吸收式空调改造成为热电冷联产,以提高热电企业经济效益的可行性.     

热电冷联产经济效益分析

以热电冷联产系统的供电煤耗,燃料节约量,当量热力系统作为评价标准,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。     

考虑减排措施的蒸汽动力系统结构优选

建立了五种典型的蒸汽动力系统结构,分别是燃烧后带减排措施的普通煤粉炉(带脱硫脱硝系统)热电联产系统(PC+ FGD+ DeNOx系统)、循环流化床锅炉(加石灰石)热电联产系统(CFB系统)、水煤浆锅炉(洗煤)热电联产系统(CWS系统)、燃气-蒸汽联合循环系统(NGCC系统)、整体煤气化联合循环系统(IGCC系统),建立...     

热电冷联产的节能分析

随着节能的不断深入发展 ,在热电联产的基础上发展了一种新的形式———热电冷联产联供。本文从火用的角度出发 ,比较了热电冷联产和热电联产电动制冷两种方式的能源利用率 ,指出热电冷联产节能的条件。     

上海力顺燃机科技有限公司

正燃气轮机热电(冷)联产诚信专业桌越创新上海力顺燃机科技有限公司是上海力顺集团成员公司,专业从事燃气轮机应用的销售、设备成套、工程承接、技术服务。作为美国SOLAR公司工业燃气轮机的中国代理,十几年来,力顺燃机公司与索拉公司携手致力于在中国大陆推广燃气轮机热电联产这种高效、节能、环保和经济效益显著的能源利用方式。截止目前为止,公司已经在国内销售Solar燃气轮机发电机组51台应用于热电(冷)联产,积累了丰富的燃气轮机热电(冷)联产项目的设计和工程服务经验。     

天然气热电冷联产的技术方案分析

天然气热电冷联产(CCHP)由于其较高的能源利用率，在全世界范围内得到了迅速的发展和广泛的利用。目前国内外相关设备已经比较成熟，因而热、电、冷相关技术参数的匹配便成为该总能系统中的技术关键，并在很大程度上影响到系统的经济效益。介绍了天然气热电冷联产系统的基本概念及发展应用情况，然后以国内某工厂CCHP系统的设计为实例，对“以热定电”和“以电定热”两种技术方案进行了参数计算和方案比较，并确定了“以电定热”的推荐方案。     

固体蓄热器蓄热过程分析与优化研究

固体蓄热器无论作为热电联产机组(CHP)的配置系统还是作为清洁电力的消纳系统都起到一定的"削峰填谷"作用.为了提高固体蓄热器的蓄热效率及蓄热容量,首先对工程常用蓄热体结构的蓄热过程提出了 一种热物理参数非定值分析方法,并通过实验验证了该数值分析方法的可靠性.对现有蓄热体结构提出截面和功率分布的优化方式,通过建立数值分析...     

意大利热电联产现状:能源政策、法规及市场自由化的影响

热电联产在意大利的应用比较普遍，但中小型热电机组的发展则比较缓慢。介绍了意大利的能源政策、法规及市场自由化对热电联产的影响，还介绍了意大利环境方面法规，意大利在热电(冷)联产方面的激励措施等。     

浅议热电冷联产

文章论述了热电冷联产节能原理,压缩制冷吸收制冷的比较,热电冷联产的市场前景。     

Dispatch strategy and model for hybrid photovoltaic and trigeneration power systems

The advent of small scale combined heat and power (CHP) systems has provided the opportunity for in-house power backup of residential-scale photovoltaic (PV) arrays. These hybrid systems enjoy a symbiotic relationship between components, but have large thermal energy wastes when operated to provide 100% of the electric load. In a novel hybrid system is proposed here of PV-trigeneration. In order to reduce waste from excess heat, an absorption chiller has been proposed to utilize the CHP-produced thermal energy for cooling of PV-CHP system. This complexity has brought forth entirely new levels of system dynamics and interaction that require numerical simulation in order to optimize system design. This paper introduces a dispatch strategy for such a system that accounts for electric, domestic hot water, space heating, and space cooling load categories. The dispatch strategy was simulated for a typical home in Vancouver and the results indicate an improvement in performance of over 50% available when a PV-CHP system also accounts for cooling. The dispatch strategy and simulation are to be used as a foundation for an optimization algorithm of such systems.     

Energy management strategy and capacity optimization for CCHP system integrated with electric-thermal hybrid energy storage system

In order to improve the comprehensive energy utilization rate of combined cooling, heating, and power (CCHP) system, a hybrid energy storage system (HESS) is proposed in this paper consisting of electric and thermal energy storage systems. And the overall optimization design and operation of CCHP system with HESS are the main problems to be solved in application. Therefore, the topology and the energy flow model of CCHP system with HESS are established and analyzed according to the energy conversion characteristics of the component equipment. Moreover, combined with five evaluative restrictions for HESS system, a rule-based energy management strategy is designed to realize the decoupling regulation of electric energy and thermal energy in CCHP system. On this basis, a multi-objective optimization model is studied by taking the indicators of annual cost ratio, the primary energy consumption ratio, and loss energy ratio, and then the capacity parameters are optimized by particle swarm optimization algorithm (PSOA). Finally, a case is carried out to compare the energy allocation situations and capacity optimization results between CCHP system with HESS and CCHP system with single thermal energy storage system (ST). Results show that the capacity of ICE is reduced by 34%, and the annual cost and the primary energy consumption are saved about 7.69% and 18.47%, respectively, demonstrating that HESS has better optimization effect and applicable for small-scale CCHP system.     

Optimization of cold-end system of thermal power plants based on entropy generation minimization

Cold-end systems are heat sinks of thermal power cycles, which have an essential effect on the overall performance of thermal power plants. To enhance the efficiency of thermal power plants, multi-pressure condensers have been applied in some large-capacity thermal power plants. However, little attention has been paid to the optimization of the cold-end system with multi-pressure condensers which have multiple parameters to be identified. Therefore, the design optimization methods of cold-end systems with single- and multi-pressure condensers are developed based on the entropy generation rate, and the genetic algorithm (GA) is used to optimize multiple parameters. Multiple parameters, including heat transfer area of multi-pressure condensers, steam distribution in condensers, and cooling water mass flow rate, are optimized while considering detailed entropy generation rate of the cold-end systems. The results show that the entropy generation rate of the multi-pressure cold-end system is less than that of the single-pressure cold-end system when the total condenser area is constant. Moreover, the economic performance can be improved with the adoption of the multi-pressure cold-end system. When compared with the single-pressure cold-end system, the excess revenues gained by using dual- and quadruple-pressure cold-end systems are 575 and 580 k$/a, respectively.     

Impingement-based high performance cooling configurations for automotive power converters

Necessitated by the dwindling supply of petroleum resources, various new automotive technologies have been actively developed from the perspective of achieving energy security and diversifying energy sources. Hybrid electric vehicles and electric vehicles are a few such examples. Such diversification requires the use of power control units essentially for power control, power conversion and power conditioning applications such as variable speed motor drives (dc–ac conversion), dc–dc converters and other similar devices. Power control unit of a hybrid electric vehicle or electric vehicle is essentially the brain of the hybrid system as it manages the power flow between the electric motor generator, battery and gas engine.Over the last few years, the performance of this power control unit has been improved and size has been reduced to attain higher efficiency and performance causing the heat dissipation as well as heat density to increase significantly. Efforts are constantly being made to reduce this size even further. As a consequence, a better high performance cooler/heat exchanger is required to maintain the active devices temperature within optimum range. Jet impingement is one such cooling scheme which has been widely used to dissipate transient and steady concentrated heat loads and can be applied to existing cooling system with minor modifications. The aim of the present study has therefore been to study the various cooling options based on impingement for application in hybrid electric vehicle and other similar consumer products and perform parametric and optimization study on the selected designs. Significant improvements in terms of thermal performance and volume reduction have been shown both experimentally and numerically.     

Modeling and optimization of a novel pressurized CHP system with water extraction and refrigeration

A novel cooling, heat, and power (CHP) system has been proposed that features a semi-closed Brayton cycle with pressurized recuperation, integrated with a vapor absorption refrigeration system (VARS). The semi-closed Brayton cycle is called the high-pressure regenerative turbine engine (HPRTE). The VARS interacts with the HPRTE power cycle through heat exchange in the generator and the evaporator. Waste heat from the recirculated combustion gas of the HPRTE is used to power the absorption refrigeration unit, which cools the high-pressure compressor inlet of the HPRTE to below ambient conditions and also produces excess refrigeration in an amount that depends on ambient conditions. Water produced as a product of combustion is intentionally condensed in the evaporator of the VARS, which is designed to provide sufficient cooling for the inlet air to the high-pressure compressor, water extraction, and for an external cooling load. The computer model of the combined HPRTE/VARS cycle predicts that with steam blade cooling and a medium-sized engine, the cycle will have a thermal efficiency of 49% for a turbine inlet temperature of 1400°C. This thermal efficiency, is in addition to the large external cooling load, generated in the combined cycle, which is 13% of the net work output. In addition, it also produces up to 1.4 kg of water for each kg of fuel consumed, depending upon the fuel type. When the combined HPRTE/VARS cycle is optimized for maximum thermal efficiency, the optimum occurs for a broad range of operating conditions. Details of the multivariate optimization procedure and results are presented in this paper. Copyright © 2008 John Wiley & Sons, Ltd.     

Particle swarm optimization for redundant building cooling heating and power system

An optimal and redundant building cooling heating and power (BCHP) system can yield economical savings, but more importantly can save energy as well as reduce the emission of pollutants. This paper presents the energy flow analysis of the conventional separation production (SP) system and the redundant BCHP system. Four decision variables (the capacity of power generation unit (PGU), the capacity of heat storage tank, the on–off coefficient of PGU and the ratio of electric cooling to cool load) to be optimized are selected in consideration of the design and the operation strategy of BCHP system. An objective function to simultaneously measure the energetic, economical and environmental benefits achieved by BCHP system in comparison to SP system is constructed and maximized. Particle swarm optimization algorithm (PSOA) is employed to search the optimal solutions. A case study of BCHP system with thermal storage unit and hybrid cooling system is presented to ascertain the feasibility and validity of the optimization method.     

寒区水源热泵及调峰供暖运行机制的优化分析

首先介绍了适用于寒区供暖的水源热泵及调峰供暖系统,指出该供暖系统的运行机制影响着运行的经济性。在不改变末端原有散热器的前提下,分析了该供暖系统主要运行参变量之间的关系。以系统运行费用为目标函数,推导出了系统运行时的优化模型。以哈尔滨某一小区从原有传统供暖方式改造为水源热泵及调峰供暖为例,对其进行了优化分析,得出了最优的系统方案及其运行情况,说明水源热泵及调峰供暖具有明显环保和经济效益。     

Ecological optimization of an irreversible Ericsson cryogenic refrigerator cycle

The ecological optimization and parametric study of an irreversible Ericsson cryogenic refrigerator cycle with finite heat capacities of external reservoirs is studied. The ecological function is defined as the cooling load minus the loss of the cooling load (the irreversibility) due to the entropy generation rate. The ecological function is optimized with respect to working fluid temperatures and the values of the cooling load, power input, the loss rate of the cooling load and COP are calculated for a typical set of operating parameters. The effects of different operating parameters on the ecological function, cooling load, the loss rate of the cooling load and COP are studied. The loss rate of the cooling load and the power input are found to be increasing functions of the cycle temperature ratio and decreasing functions of COP while the COP is found to be a decreasing function of the cycle temperature ratio. On the other hand, there exist the optimal values of the cycle temperature ratio and COP at which the ecological function and cooling load attain their maximum values. Also the ecological function and the cooling load are found to be increasing functions of the sink‐side heat capacitance rate and the effectiveness on the source‐, sink‐, and regenerative‐side heat exchangers while the decreasing functions of the source‐side heat capacitance rate. Copyright © 2005 John Wiley & Sons, Ltd.     

Solid oxide fuel cell/gas turbine trigeneration system for marine applications

Shipping contributes 4.5% to global CO₂ emissions and is not covered by the Kyoto Agreement. One method of reducing CO₂ emissions on land is combined cooling heating and power (CCHP) or trigeneration, with typical combined thermal efficiencies of over 80%. Large luxury yachts are seen as an ideal entry point to the off-shore market for this developing technology considering its current high cost.This paper investigates the feasibility of combining a SOFC-GT system and an absorption heat pump (AHP) in a trigeneration system to drive the heating ventilation and air conditioning (HVAC) and electrical base-load systems. A thermodynamic model is used to simulate the system, with various configurations and cooling loads. Measurement of actual yacht performance data forms the basis of this system simulation.It is found that for the optimum configuration using a double effect absorption chiller in Ship 1, the net electric power increases by 47% relative to the electrical power available for a conventional SOFC-GT-HVAC system. This is due to more air cooled to a lower temperature by absorption cooling; hence less electrical cooling by the conventional HVAC unit is required. The overall efficiency is 12.1% for the conventional system, 34.9% for the system with BROAD single effect absorption chiller, 43.2% for the system with double effect absorption chiller. This shows that the overall efficiency of a trigeneration system is far higher when waste heat recovery happens.The desiccant wheel hardly reduces moisture from the outdoor air due to a relative low mass flow rate of fuel cell exhaust available to dehumidify a very large mass flow rate of HVAC air, Hence, desiccant wheel is not recommended for this application.     

热泵干燥系统的空气旁通率的遗传算法优化

首先介绍了适用于干燥领域的热泵干燥系统,空气的旁通率影响着干燥系统的有效性与经济性。综合考虑系统除湿效果和热泵机组运转能耗,推导出了系统除湿时的优化模型。以某一具体问题为例,采用遗传算法对热泵干燥系统除湿比能耗进行了优化,得出了空气最佳旁通率及其运行情况,对热泵干燥系统的设计、运行具有一定的指导作用。