太阳能与燃煤机组混合发电系统集成方式的研究

阐述了太阳能与燃煤机组混合发电系统的3种集成方式:太阳能集热场与锅炉并联,太阳能集热场与加热器并联及太阳能集热场与锅炉、加热器二者并联.采用传统的绝对电效率、标准煤耗以及太阳能热发电效率作为经济性指标,并利用热平衡方法对混合系统的热经济性指标进行了计算.以200 MW机组热力系统为例,对3种集成方式下机组的热经济性指标进行了比较,对不同辐射强度下机组热经济性指标的变化规律进行了分析,并确定混合发电的最优集成方式.结果表明:太阳能与燃煤机组混合发电时,太阳能热发电效率高于单纯的太阳能热发电,且燃煤机组煤耗率降低;在3种集成方式中,太阳能集热场与锅炉并联时,太阳能热效率最高、节煤量最多.     

太阳能与燃煤机组混合发电方式的热经济性研究

阐述了分别从锅炉蒸发受热面、高压加热器汽侧和汽轮机低压缸引入太阳热能与燃煤机组进行混合发电的3种集成方案,定义了太阳能热电转换率、单位时间节煤量及太阳能热贡献率等评价指标,并以某300 MW燃煤机组为例,应用变热量等效焓降法计算理论对3种太阳能与燃煤机组混合发电集成方案的热经济性指标进行了计算和比较,确定了混合发电的最优集成方式,并对其经济性进行了初步分析.结果表明：混合发电集成方案2-1（取代2号高压加热器抽汽）的热经济性指标、运行安全性和稳定性均较好,因此选取方案2-1作为混合发电最优集成方案;太阳能的单位发电成本为0.63元/（kW·h）,低于单纯太阳能发电站的0.75～1.85元/（kW·h）.     

塔式太阳能与燃煤互补复合发电系统技术经济性分析

提出塔式太阳能与燃煤机组复合发电系统的优化集成方案,建立复合发电系统技术经济性评价的分析计算模型,以330 MW机组为例,对3种集成方案的技术经济性进行模拟计算。结果表明,塔式太阳能与燃煤机组复合发电系统的热功转换效率高于纯塔式太阳能低于燃煤机组,通过单方案判断、多方案比选和财务盈利能力的分析得出,塔式太阳能产生的蒸汽引入燃煤机组主蒸汽是较理想的选择,其热功转换效率约为42.8%,太阳能净发电成本为2.68$/k Wh。     

太阳能蒸汽与燃煤机组集成系统分析

基于我国当前火力发电状况,提出将太阳能蒸汽作为火电厂辅助蒸汽系统辅助热源的集成发电方案。以某600MW机组为例,提出多种太阳能蒸汽与燃煤机组集成方案,并分别对各方案进行热力计算及热经济性分析。结果表明:选取的集成方案不同,系统的热经济性不同;被取代蒸汽品质及数量越高,集成系统热经济性越好。     

太阳能辅助燃煤热发电系统的探讨

由于太阳能供给的间歇性,单独投资建造的太阳能热发电系统经常会出现设备成本高、利用率低、收益低等问题。因此,利用太阳能热发电系统与常规燃煤发电系统都有汽轮机部分这一特点,将槽式抛物太阳能集热器集成到常规燃煤发电系统中,寻求改造现有燃煤发电系统的新途径。以某300 MW机组为例,利用弗留格尔公式进行变工况计算,然后进行热经济性分析,为太阳能辅助燃煤热发电混合系统的建立提供理论参考。     

太阳能与燃煤机组混合发电系统的热经济性分析

以某型300 MW机组为例,利用抛物面槽式集热器收集太阳能热量,提出7种太阳能与燃煤机组集成方案,并定义太阳能加热给水与燃煤机组混合发电系统的循环效率、太阳能热电转换率等评价指标,应用变热量等效焓降法计算理论,对原机组及不同集成方案进行热经济性能分析。结果表明:太阳能与回热系统混合发电,既能增加发电量,提高太阳能热电效率,又能降低纯太阳能发电投资成本,其代价是混合发电系统的热效率将下降;给出的所有集成方案中,取代1段抽汽方案产生的额外电能和太阳能热电转换率最大,标煤耗率和热耗率最小,为最佳混合方案。     

太阳能与燃煤机组集成发电系统的研究现状

介绍了太阳能与燃煤机组集成发电系统的发展背景、国内外发展状况以及集成方式,对太阳能与回热系统集成等三种集成方式进行了比较,分析了几种提高集成发电系统经济性的优化方式,指出了发展中存在的一些问题及发展前景。     

CO2减排机理及与燃煤电厂集成特性的研究

推导了CO2吸收工艺系统再生能耗计算公式,分析了吸收剂性质对再生能耗的影响,计算得到不同质量分数下吸收剂的再生能耗;提出几种基于槽式太阳能辅助燃煤发电技术的CO2减排集成方案,以N600-24.2/566/566型发电机组为例,以集成系统热耗率、发电标准煤耗率和热效率作为经济性指标,采用热平衡法对不同集成方案机组的热经济性指标进行了计算和比较.结果表明:在加入太阳能热量和机组主蒸汽质量流量不变的情况下,集成方案5在设计辐照强度下的热耗率和发电标准煤耗率均最低,是最经济的集成方案.     

CO_2减排机理及与燃煤电厂集成特性的研究

推导了CO2吸收工艺系统再生能耗计算公式,分析了吸收剂性质对再生能耗的影响,计算得到不同质量分数下吸收剂的再生能耗;提出几种基于槽式太阳能辅助燃煤发电技术的CO2减排集成方案,以N600-24.2/566/566型发电机组为例,以集成系统热耗率、发电标准煤耗率和热效率作为经济性指标,采用热平衡法对不同集成方案机组的热经济性指标进行了计算和比较.结果表明:在加入太阳能热量和机组主蒸汽质量流量不变的情况下,集成方案5在设计辐照强度下的热耗率和发电标准煤耗率均最低,是最经济的集成方案.     

槽式太阳能与火电机组联合系统的经济性分析

针对太阳能与火电机组联合运行系统提出3种集成方案:太阳能集热系统与机组回热系统并联;太阳能集热系统与锅炉汽化段并联;太阳能集热系统与机组回热系统及锅炉汽化段并联。以槽式太阳能与600 MW亚临界火电机组联合为例,对3种方案进行经济性分析,并对最优方案太阳能部分做能源平均成本(LEC)计算。结果表明:3种方案(尤以第3种方案最佳)均可有效减少燃煤量,降低CO_2排放量,最优方案中LEC低于单纯太阳能发电成本,具有经济可行性。     

Advancement in solar photovoltaic/thermal (PV/T) hybrid collector technology

This article presents an overview on the research and development and application aspects for the hybrid photovoltaic/thermal (PV/T) collector systems. A major research and development work on the photovoltaic/thermal (PVT) hybrid technology has been done since last 30 years. Different types of solar thermal collector and new materials for PV cells have been developed for efficient solar energy utilization. The solar energy conversion into electricity and heat with a single device (called hybrid photovoltaic thermal (PV/T) collector) is a good advancement for future energy demand. This review presents the trend of research and development of technological advancement in photovoltaic thermal (PV/T) solar collectors and its useful applications like as solar heating, water desalination, solar greenhouse, solar still, photovoltaic-thermal solar heat pump/air-conditioning system, building integrated photovoltaic/thermal (BIPVT) and solar power co-generation.     

Review of latent thermal energy storage systems for solar air-conditioning systems

Solar air conditioning is an important approach to satisfy the high demand for cooling given the global energy situation. The application of phase-change materials (PCMs) in a thermal storage system is a way to address temporary power problems of solar air-conditioning systems. This paper reviews the selection, strengthening, and application of PCMs and containers in latent thermal storage system for solar air-conditioning systems. The optimization of PCM container geometry is summarized and analyzed. The hybrid enhancement methods for PCMs and containers and the cost assessment of latent thermal storage system are discussed. The more effective heat transfer enhancement using PCMs was found to mainly involve micro-nano additives. Combinations of fins and nanoadditives, nanoparticles, and metal foam are the main hybrid strengthening method. However, the thermal storage effect of hybrid strengthening is not necessarily better than single strengthening. At the same time, the latent thermal storage unit has less application in the field of solar air-conditioning systems, especially regarding heat recovery, because of its cost and thermal storage time. The integration of latent thermal storage units and solar air-conditioning components, economic analysis of improvement technology, and quantitative studies on hybrid improvement are potential research directions in the future.     

A review on modeling of solar photovoltaic systems using artificial neural networks,fuzzy logic,genetic algorithm and hybrid models

The uncertainty associated with modeling and performance prediction of solar photovoltaic systems could be easily and efficiently solved by artificial intelligence techniques. During the past decade of 2009 to 2019, artificial neural network (ANN), fuzzy logic (FL), genetic algorithm (GA) and their hybrid models are found potential artificial intelligence tools for performance prediction and modeling of solar photovoltaic systems. In addition, during this decade there is no extensive review on applicability of ANN, FL, GA and their hybrid models for performance prediction and modeling of solar photovoltaic systems. Therefore, this article focuses on extensive review on design, modeling, maximum power point tracking, fault detection and output power/efficiency prediction of solar photovoltaic systems using artificial intelligence techniques of the ANN, FL, GA and their hybrid models. In addition, the selected articles on the solar radiation prediction using ANN, FL, GA and their hybrid models are also summarized. Total of 122 articles are reviewed and summarized in the present review for the period of 2009 to 2019 with 90 articles in the field of {ANN, FL, GA and their hybrid models} + solar photovoltaic systems and 32 articles in the field of {ANN, FL, GA and their hybrid models} + solar radiation. The review shows the suitability and reliability of ANN, FL, GA and hybrid models for accurate prediction of the solar radiation and the performance characteristics of solar photovoltaic systems. In addition, this review presents the guidance for the researchers and engineers in the field of solar photovoltaic systems to select the suitable prediction tool for enhancement of the performance characteristics of the solar photovoltaic systems and the utilization of the available solar radiation.     

Solar gas turbine systems: Design, cost and perspectives

The combination of high solar shares with high conversion efficiencies is one of the major advantages of solar gas turbine systems compared to other solar-fossil hybrid power plants. Pressurized air receivers are used in solar tower plants to heat the compressed air in the gas turbine to temperatures up to 1000 °C. Therefore solar shares in the design case of 40% up to 90% can be realized and annual solar shares up to 30% can be achieved in base load. Using modern gas turbine systems in recuperation or combined cycle mode leads to conversion efficiencies of the solar heat from around 40% up to more than 50%. This is an important step towards cost reduction of solar thermal power. Together with the advantages of hybrid power plants—variable solar share, fully dispatchable power, 24 h operation without storage—solar gas turbine systems are expected to have a high potential for market introduction in the mid term view.In this paper the design and performance assessment of several prototype plants in the power levels of 1 MW, 5 MW and 15 MW are presented. Advanced software tools are used for design optimization and performance prediction of the solar tower gas turbine power plants. Detailed cost assumptions for the solarized gas turbine, the solar tower plant and further equipment as well as for operation and maintenance are presented. Intensive performance and economic analysis of the prototype plants for different locations and capacity factors are shown. The cost reduction potential through automation and remote operation is revealed.     

The economics of hybrid power systems for sustainable desert agriculture in Egypt

Egypt has embarked on an ambitious desert land reclamation program in order to increase total food production. Energy planners for these desert agriculture locations have chosen diesel generation power technology because minimization of the initial capital cost of a power supply system is their top priority. This heavy reliance on diesel generation has negative effects on the surrounding environment including soil, groundwater, and air pollution. Although good solar and wind resource prospects exist for the use of cleaner hybrid power systems in certain desert locations, little research has been done to investigate the economic potential of such systems in Egypt’s desert agriculture sector. Using optimization software, we assess the economics of hybrid power systems versus the present diesel generation technology in a remote agricultural development area. We also consider the emission reduction advantages of using hybrid systems. Interestingly enough, optimization results show that hybrid systems are less costly than diesel generation from a net present cost perspective even with the high diesel fuel price subsidies. Since hybrids are also more environmentally friendly, they represent a strong step towards achieving sustainable desert agriculture.     

Solar Thermal Power Towers

The solar thermal central receiver technology, known as solar power towers, is rapidly evolving to a state of near-term energy availability for electrical power generation and industrial process heat applications. The systems consist of field arrays of heliostat reflectors, a central receiver boiler, short term thermal storage devices, and either turbine-generators or heat exchangers. Fluid temperatures up to 550°C are currently achievable, and technology developments are underway to reach 1100°C. Six solar power towers are now under construction or in test operation in five countries around the world.     

Grid connected fuel cell and PV hybrid power generating system design with Matlab Simulink

Renewable energy sources have been taken the place of the traditional energy sources and especially rapidly developments of photovoltaic (PV) technology and fuel cell (FC) technology have been put forward these renewable energy sources (RES) in all other RES. PV systems have been started to be used widely in domestic applications connected to electrical grid and grid connected PV power generating systems have become widespread all around the world. On the other hand, fuel cell power generating systems have been used to support the PV generating so hybrid generation systems consist of PV and fuel cell technology are investigated for power generating. In this study, a grid connected fuel cell and PV hybrid power generating system was developed with Matlab Simulink. 160 Wp solar module was developed based on solar module temperature and solar irradiation by using real data sheet of a commercial PV module and then by using these modules 800 Wp PV generator was obtained. Output current and voltage of PV system was used for input of DC/DC boost converter and its output was used for the input of the inverter. PV system was connected to the grid and designed 5 kW solid oxide fuel cell (SOFC) system was used for supporting the DC bus of the hybrid power generating system. All results obtained from the simulated hybrid power system were explained in the paper. Proposed model was designed as modular so designing and simulating grid connected SOFC and PV systems can be developed easily thanks to flexible design.     

Technico-economic analysis of off grid solar PV/Fuel cell energy system for residential community in desert region

A technico-economic analysis based on integrated modeling, simulation, and optimization approach is used in this study to design an off grid hybrid solar PV/Fuel Cell power system. The main objective is to optimize the design and develop dispatch control strategies of the standalone hybrid renewable power system to meet the desired electric load of a residential community located in a desert region. The effects of temperature and dust accumulation on the solar PV panels on the design and performance of the hybrid power system in a desert region is investigated. The goal of the proposed off-grid hybrid renewable energy system is to increase the penetration of renewable energy in the energy mix, reduce the greenhouse gas emissions from fossil fuel combustion, and lower the cost of energy from the power systems. Simulation, modeling, optimization and dispatch control strategies were used in this study to determine the performance and the cost of the proposed hybrid renewable power system. The simulation results show that the distributed power generation using solar PV and Fuel Cell energy systems integrated with an electrolyzer for hydrogen production and using cycle charging dispatch control strategy (the fuel cell will operate to meet the AC primary load and the surplus of electrical power is used to run the electrolyzer) offers the best performance. The hybrid power system was designed to meet the energy demand of 4500 kWh/day of the residential community (150 houses). The total power production from the distributed hybrid energy system was 52% from the solar PV, and 48% from the fuel cell. From the total electricity generated from the photovoltaic hydrogen fuel cell hybrid system, 80.70% is used to meet all the AC load of the residential community with negligible unmet AC primary load (0.08%), 14.08% is the input DC power for the electrolyzer for hydrogen production, 3.30% are the losses in the DC/AC inverter, and 1.84% is the excess power (dumped energy). The proposed off-grid hybrid renewable power system has 40.2% renewable fraction, is economically viable with a levelized cost of energy of 145 $/MWh and is environmentally friendly (zero carbon dioxide emissions during the electricity generation from the solar PV and Fuel Cell hybrid power system).     

A comparison of GaAs and Si hybrid solar power systems

Various silicon hybrid systems are modeled and compared with a Gallium Arsenide hybrid system. The hybrid systems modeled produce electric power and also thermal power which can be used for heating or air conditioning. Various performance indices are defined and are used to compare the system performance. The performance indices are: capital cost per unit electric power out; capital cost per total power out; capital cost per unit electric power plus mechanical power; annual cost per unit electric energy; and annual cost per unit electric plus mechanical work. These performance indices indicate that concentrator hybrid systems can be cost effective when compared with present day energy costs. Realistic costs and efficiencies of GaAs and Si are respectively $35,000/m² for 15 per cent efficient solar cells and $1000/m² for 10 per cent efficient solar cells based on information available at the time of this study in late 1975. The performance indices show that the limiting values for annual costs are 10.3¢/kWh and 6.8¢/kWh for Si and GaAs respectively. Results demonstrate that for a given flow rate there is an optimal operating condition for maximum photovoltaic output associated with concentrator systems. Also concentrator hybrid systems produce a distinct cost advantage over flat hybrid systems.