浅层地热能+太阳能联合系统在冀南地区新农居中的应用

以河北省冀南地区某新农村住宅为研究对象，分析太阳能资源和浅层地热能资源的分布规律和特征，提出2种运行模式，进行了全年运行数据监测，从技术性和经济性等角度对联合系统和单一系统的运行效果进行综合对比分析。结果表明：联合系统的综合性能优于单一地源热泵系统，在冀南地区采用联合系统更高效节能。     

综合能源系统运行优化设计与运行策略研究

综合能源系统能整合协调各异质能源,是提高能源利用率和降低运行费用的有效途径。提出了两种运行策略及一种基于穷举法的优化策略方法,建立了包括小型燃气轮机系统、地源热泵、电制冷机、吸收式制冷机、换热器的综合能源系统能量转换模型。在案例研究中,提出了以典型日费用最小为目标的综合能源系统优化方案,对以电定热、以热定电两种运行策略下的场景进行了优化分析,确定设备的最佳容量和运行参数,给出了运行策略对比分析结果。结果表明：以电定热策略的整体经济性优于以热定电策略约10%;与传统供能系统在经济性上的适用性进行对比发现,综合能源系统成本节省比例在5%～30%之间。     

火电机组的热经济性分析

为进行整个火电机组的能量系统热经济性分析及考察其组元变化的影响，提出了以热经济学和边际成本概念为基础的热经济性分析方法。对复杂能量系统主要以功能划分后形成的组元，考察其组元的输出炯流变化引起整个系统的能耗变化，可以通过边际炯成本、单位炯成本和组元产品的函数来表达，来衡量整个系统所有组元的输出炯流变化对系统外部输入燃料的影响，便于火电机组的运行经济状态动态评估。通过300MW机组主蒸汽参数变化的计算表明：参数变化时将引起系统的煤耗增加，降低了经济性，因而从本质上进行了热经济性的全面综合分析，以优化机组运行，进行性能诊断。图1表2参10     

超临界机组热力系统变工况下经济性分析

研究和分析加热器经济性指标与运行工况的关系、更好地掌握加热器系统特征、提高系统的运行水平是提高机组经济性和安全性的关键。运用基于热力学第一定律的等效焓降法和基于热力学第二定律的分析法对加热器系统特征进行分析研究。等效焓降理论热力系统热经济性计算的通用矩阵方程能有效克服热经济性矩阵分析方法需要联立其它方程才能求解热力系统最终热经济性指标的缺陷。分析法为评价能量转换的"量"和"质"提供了统一的尺度。综合考虑上述方法,分析加热器系统特征,为准确评价热力系统的热经济性提供依据。     

蓄冷空调系统运行评价方法研究及影响因素分析

通过对现有蓄冷空调系统运行过程中能耗和经济性评价方法的分析,为了更好的、全面的评价蓄冷空调系统运行过程中的能耗经济性,提出用单位冷量能效经济系数评价蓄冷空调系统运行过程中能效性和经济性,并对影响蓄冷空调系统运行过程中单位冷量能效经济系数变化的因素进行了初步的分析。     

熔盐塔式太阳能热发电站中蒸汽发生系统水循环方式的对比分析

蒸汽发生系统水循环方式的选择对熔盐塔式太阳能热发电站的投资经济性及安全稳定运行至关重要。对熔盐塔式太阳能热发电站的蒸汽发生系统进行了介绍，对蒸汽发生系统的两种水循环方式——自然循环方式和强制循环方式进行了技术性和经济性对比分析。分析结果表明：在目前熔盐塔式太阳能热发电站采用高温、超高压参数下，自然循环方式及强制循环方式技术路线均能满足熔盐塔式太阳能热发电站蒸发换热的需求；若选择强制循环方式，在设备选型时，应将强制循环泵的结构及运行环境作为重点进行综合分析；结合国内已建成的熔盐塔式太阳能热发电项目的运行经验及太阳能热发电技术的发展趋势，熔盐塔式太阳能热发电站蒸汽发生系统的出口主蒸汽压力在亚临界以下(<16 MPa)时，从技术性、经济性及运行维护方面综合考虑，水循环方式推荐采用自然循环方式。以期为熔盐塔式太阳能热发电站蒸汽发生系统的设计选型提供参考。     

基于阶梯型碳交易机制的综合能源系统低碳经济调度

为实现综合能源系统的经济低碳运行,提出了计及阶梯型碳交易机制的综合能源系统优化模型,首先以系统全年运行维护成本和投资成本最小为目标,建立了考虑多元负荷需求的综合能源系统容量优化模型,其次基于k-means聚类方法及平均值法选取典型日冷热负荷,最后以系统运行维护成本以及碳交易成本最小为目标,分析不同基准碳价对系统运行方式、碳排放量以及经济性的影响,并以典型日进行详细分析。结果表明：将阶梯型碳交易机制引入综合能源系统可以有效降低碳排放量并提高系统的经济性,尤其对于供热季,能以较低基准碳价对系统产生显著影响。     

汽轮机回热加热系统节能潜力分析与改进

根据对50MW双抽汽轮机回热加热系统试验研究分析，找出了给水回热系统在设计和运行管理中存在的问题，并定量分析了存在的问题对机组运行经济性的影响。提出了给水回热加热系统的改进措施，使50MW机组回热系统的经济运行状况得到很大的改善。     

燃料电池混合动力机车参数匹配与等效氢耗优化能量管理方法

为提升燃料电池机车混合动力系统综合经济性，基于机车动力性能分析提出一种基于配置成本优化的燃料电池混合动力系统参数匹配方法。在此基础上，将锂电池能耗等效为燃料电池的氢气消耗，并提出一种基于等效氢耗实时优化的燃料电池混合动力系统能量管理方法，以降低系统整体能耗水平。基于某机车实际参数对所提方法进行可行性验证。结果表明，机车配置10套150 kW的燃料电池和549串16并的锂电池，可在机车安全稳定运行的基础上，实现系统总购置成本最优，并且，基于所提出的能量管理方法，系统等效氢气消耗降低8.44%，混合动力系统的综合经济性得到明显改善。     

太阳能和锅炉烟气余热联合的供热系统及其经济性

某供热系统因实际可用热功率与用热设备功率有较大差距，导致不能满足供热需求，系统运行压力低，锅炉疲劳运行，经济性差，为此提出将太阳能集热系统和锅炉烟气余热利用系统与现系统并网的措施，阐述了系统设备构成及运行控制，经济性分析表明节煤效果显著。     

Comparison of performance for cascaded humidified advanced turbine with the corresponding combined system

In this paper, the use of a cascaded humidified advanced turbine (CHAT) system instead of a cascaded advanced combined turbine (CACT) system to increase the overall efficiency is discussed. The overall performance is calculated for CHAT and CACT systems.

The working parameters in this study are the overall pressure ratio, ambient temperature, and altitude. Using a specially designed program, the effect of these parameters on the specific power output, specific fuel consumption, engine thermal efficiency, and the overall efficiency is evaluated and compared.

The results showed superior CHAT system performance relative to the CACT system. The specific power output, the specific fuel consumption, and the overall efficiency of the two systems at design point are compared as follows: the specific power output for CHAT system is about 5% more than CACT at design point, the specific fuel consumption for CHAT is about 7% less than CACT at design point, and the efficiency for CHAT system is about 7% more than CACT at design point. Thus the CHAT system demonstrates better performance at higher temperatures and part-load operation. It is interesting to notice that the effect of altitude on both systems is almost the same.     

A new solar and geothermal based integrated ammonia fuel cell system for multigeneration

In this study, a new solar and geothermal based integrated system is developed for multigeneration of electricity, fresh water, hydrogen and cooling. The system also entails a solar integrated ammonia fuel cell subsystem. Furthermore, a reverse osmosis desalination system is used for fresh water production and a proton exchange membrane based hydrogen production system is employed. Moreover, an absorption cooling system is utilized for district cooling via available system waste heat. The system designed is assessed thermodynamically through approaches of energy and exergy analyses. The overall energy efficiency is determined to be 42.3%. Also, the overall exergy efficiency is assessed, and it is found to be 21.3%. The exergy destruction rates in system components are also analysed and the absorption cooling system generator as well as geothermal flash chamber are found to have comparatively higher exergy destruction rates of 2370.2 kW and 643.3 kW, respectively. In addition, the effects of varying system parameters on the system performance are studied through a parametric analyses of the overall system and associated subsystems.     

Process development of a solar-assisted multi-production plant: Power,cooling, and hydrogen

Multi-production is a practical approach to boost the efficiency of energy conversion systems by utilizing waste energy to producing more commodities in comparison to conventional single output plants. Solar energy is a vast source of energy that has the potential to be employed for different purposes. Therefore, in this research, a solar-driven multi-production system of power, cooling, and hydrogen generation is proposed and evaluated for being implemented in the city of Bandar-Abbas. The overall system is evaluated by calculating the exergy efficiency and exergy destruction rate of each equipment of the multi-production system. Based on the obtained results, heat exchangers, valves and drums, and splitters monitor to be the most exergy destructive equipment compared to other equipment in the multi-production system. In overall, the designed multi-production system reaches the overall energy efficiency of 90.77% and the overall exergy efficiency of 92.19%. In addition, the coefficient of performance is 0.39 for the absorption refrigeration cycle of the designed multi-production system. In overall, the designed system is able to produce 4.36 MW of electricity, 1.65 MW of cooling load, and 2026 kg/h of hydrogen generation at 80.86°C and 2068 kPa.     

Performance evaluation of a geothermal based integrated system for power,hydrogen and heat generation

In the present study, an integrated system is proposed and thermodynamically analyzed to reduce greenhouse gas (GHG) emissions while improving overall system performance. The integrated system is comprised of a supercritical carbon dioxide (CO₂) Rankine cycle cascaded by an Organic (R600) Rankine cycle, an electrolyzer, and a heat recovery system. It is designed to utilize a medium-to-high temperature geothermal energy source for power and hydrogen production, and thermal energy utilization for space heating. Therefore, parametric studies for the supercritical CO₂ cycle, the Organic (R600) cycle, and the overall system are conducted. In addition, the effect of various operational conditions, such as geothermal source, ambient and cooling water temperatures on the performance of each cycle and the integrated system, is illustrated. It is found that increasing geothermal source temperature results in slight increases of the exergetic efficiency of the overall system. The energy efficiencies of the CO₂ and Organic Rankine cycles do not considerably vary with source temperature changes. The decay of the cooling water temperature leads to a decrease in the overall system exergetic efficiency. The system configuration, which is introduced, is capable of producing about 180 kg/h for the geothermal source of mass flow rate of 40 kg/s and a temperature of 473 K.     

Modified exergoeconomic modeling of geothermal power plants

In this study, a modified exergoeconomic model is proposed for geothermal power plants using exergy and cost accounting analyses, and a case study is in this regard presented for the Tuzla geothermal power plant system (Tuzla GPPS) in Turkey to illustrate an application of the currently modified exergoeconomic model. Tuzla GPPS has a total installed capacity of 7.5 MW and was recently put into operation. Electricity is generated using a binary cycle. In the analysis, the actual system data are used to assess the power plant system performance through both energy and exergy efficiencies, exergy losses and loss cost rates. Exergy efficiency values vary between 35% and 49% with an average exergy efficiency of 45.2%. The relations between the capital costs and the exergetic loss/destruction for the system components are studied. Six new exergetic cost parameters, e.g., the component annualized cost rate, exergy balance cost, overall unavoidable system exergy destruction/loss cost rate, overall unavoidable system exergy destruction/loss cost rate, overall unavoidable system exergy production cost rate and the overall unavoidable system exergy production cost rate are studied to provide a more comprehensive evaluation of the system.     

Recent advances of hydrogen production through particulate semiconductor photocatalytic overall water splitting

Solar energy-driven photocatalytic water splitting has been investigated for decades to produce clean and renewable green hydrogen. In this paper, the cutting-edge research within the overall water splitting system is summarized from the one-step photocatalytic overall water splitting (POWS) system to the two-step system and the cocatalysts research in this field. In addition, the photocatalytic reaction engineering study is also reviewed which is crucial for future scale-up. This mini-review provides a picture of survey of recent progress of relevant overall water splitting system, with particular attention paid to material system and mechanistic breakthroughs, and highlights the challenge and opportunity of the current system.     

Photovoltaic thermal hybrid solar system for residential applications

Electrical and thermal energy have wide applications for the future of mankind. A solar photovoltaic thermal system is a hybrid system, which can produce both thermal and electrical energy. Chennai has an appropriate climate and is highly suitable for using photovoltaic thermal hybrid systems. This article presents the mathematical analyses of the thermal, electrical, and exergetic performance of a photovoltaic thermal system augmented by a flat plate collector for a typical domestic application. The system is found to have 11% average electrical efficiency, 15% overall exergy efficiency, and 56% overall energy efficiency.     

An integral criterion for appraising the overall quality of acomputer-based hydroturbine governing system

In this paper, an integral criterion is developed for the overall analysis and appraisal of the performance, reliability and economy of a computer-based control system. A concept of performability is discussed, and the economic optimality is based on the overall benefits from the manufacturer to the user. A case study for a hydroturbine governing system is given. A comparison between different system configurations shows that it is helpful and beneficial to select a system possessing high indices and excellent quality     

调水系统中关键建筑物的重要性权重的确定方法

调水系统包括众多的建筑物，确定各个建筑物在系统中的权重，对于系统的运行维护、风险评估及分析具有重要的意义。给出最小二乘法意义下的权重求取办法，J不仅反映调水系统中各建筑物整体的比例关系，而且反映出单体建筑物之间的细微差别。通过本算法求出的权重系数既考虑了全局又考虑了局部的细微区别。本算法同样可以适用于单体建筑物不同组成部分权重的求取。     

燃气-蒸汽联合循环系统设计与蒸汽系统参数分析研究

研究了蒸汽系统的参数选择对联合循环部件及总体性能的影响，通过对单压、双压和三压三种蒸汽系统参数配置方案的设计计算和分析。初步得到了联合循环热力系统合理设计的一些基本原则，研究结果对联合循环系统的总体优化设计具有一定的参考价值。