Proposal of a Solar Thermal Power Plant at Low Temperature Using Solar Thermal Collectors

To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surface solar collectors, so working at low temperature (i.e., below 100°C). This power plant is aimed at warm countries, i.e., the ones mainly located between -40° and 40° latitude, having available space along their coast. This land based plant, to install on the seashore, is technologically similar to the one used for OTEC (Ocean Thermal Energy Conversion). This plant, apart from supplying electricity with a much better thermodynamic efficiency than OTEC plants, has the main advantage of providing desalinated water for drinking and irrigation. This plant is designed to generate electricity (and desalinated water) night and day and all year round, by means of hot water storage, with just a variation of the power delivered depending on the season.

Demonstration of Pilot Scale Large Aperture Parabolic Trough Organic Rankine Cycle Solar Thermal Power Plant in Louisiana

During the calendar year of 2012 the University of Louisiana at Lafayette in conjunction with CLECO Power LLC (CLECO) has constructed and commissioned a pilot scale parabolic trough solar thermal power plant for the first time in Louisiana. The large aperture trough (LAT) solar collectors were provided by Gossamer Space Frames and are coupled with an organic Rankine cycle (ORC) power block provided by ElectraTherm, Inc. for study of the feasibility of cost-effective commercial scale solar thermal power production in Louisiana. Supported by CLECO and providing power to the existing CLECO grid, the implementation of state-of-the-industry collector frames, mirrors, trackers, and ORC power block is studied under various local weather conditions which present varied operating regimes from existing solar thermal installations. The solar collectors provide a design output of 650 kWth and preliminary actual performance data from the system level is presented. The optimal size, configuration and location for such a plant in the given solar resource region are being studied in conjunction with CLECO’s search for optimal renewable energy solutions for the region. The pilot scale size of the facility and implementation of the simpler ORC allow remote operation of the facility and flexibility in operating parameters for optimization studies. The construction of the facility was supported by the Louisiana Department of Natural Resources, the U.S. Department of Energy, and CLECO. The continued operation of the plant is supported by CLECO Power LLC and the University of Louisiana at Lafayette.

Optimization of solar thermal power station LCOE based on NSGA-Ⅱ algorithm

In view of the high cost of solar thermal power generation in China,it is difficult to realize large-scale production in engineering and industrialization.Non-dominated sorting genetic algorithm II(NSGA-II)is applied to optimize the levelling cost of energy(LCOE)of the solar thermal power generation system in this paper.Firstly,the capacity and generation cost of the solar thermal power generation system are modeled according to the data of several sets of solar thermal power stations which have been put into production abroad.Secondly,the NSGA-II genetic algorithm and particle swarm algorithm are applied to the optimization of the solar thermal power station LCOE respectively.Finally,for the linear Fresnel solar thermal power system,the simulation experiments are conducted to analyze the effects of different solar energy generation capacities,different heat transfer mediums and loan interest rates on the generation price.The results show that due to the existence of scale effect,the greater the capacity of the power station,the lower the cost of leveling and electricity,and the influence of the types of heat storage medium and the loan on the cost of leveling electricity are relatively high.

Increasing Coal-Fired Power Plant Operational Flexibility by Integrating Solar Thermal Energy and Compressed Air Energy Storage System

This paper proposed a novel integrated system with solar energy,thermal energy storage(TES),coal-fired power plant(CFPP),and compressed air energy storage(CAES)system to improve the operational flexibility of the CFPP.A portion of the solar energy is adopted for preheating the boiler’s feedwater,and another portion is stored in the TES for the CAES discharging process.Condensate water from the CFPP condenser is used for cooling compressed air during the CAES charging process.The thermodynamic performance of the integrated system under different load conditions is studied.The system operations in a typical day are simulated with EBSILON software.The system enables daily coal saving of 9.88 t and reduces CO_(2)emission by 27.95 t compared with the original CFPP at 100%load.Under partial load conditions,the system enables maximum coal saving of 10.29 t and maximum CO_(2)emission reduction of 29.11 t at 75%load.The system has maximum peak shaving depth of 9.42%under 40%load condition.The potential of the system participating ancillary service is also discussed.It is found that the integration of solar thermal system and CAES system can bring significant ancillary service revenue to a conventional CFPP.

Thermo-Economic Optimization of Solar Thermal Devices by Coherent Integration of Technologies

Radiation is a form of energy where the angular variable of the direction of its photons has a primary importance, particularly for radiation concentration processes, which are essential tools to reach high temperatures from radiation beams (as the solar ones) with moderate intensities. Solar radiation cannot be used directly to feed thermodynamic cycles, and optical concentration must be applied to that goal. In general, reflection from mirrors is preferred to refraction by lenses in this case, because they have less optical aberrations. Concentration conveys very high temperatures in the receiver. However, the higher the temperature, the lower the efficiency of the solar thermal apparatus. Besides that, economy also suffers quite a lot when going to very high concentration factors, which is one of the main burdens in the development of Solar Thermal Energy. A new configuration of solar radiation concentrator is presented. It includes a salient innovation in the way the mirrors are given the right curvature by mechanical forces. Those mirrors are originally flat and do not need any special thermal treatment for this purpose. The whole device concept has been guided by the principle of thermoeconomic coherence, which requires similar efforts in all degrees of freedom that have strong influence in the performance and cost of the system. The paper shows the decision tree that has oriented the project, following the principle of equilibrium in efforts, which leads to a design window of moderate values in the main variables. The prototype of this new configuration has already been built, and the first stage of research is considered to be finished, because the prototype has shown excellent conditions to include selected (fitting) technologies at a very low cost.

Potential Map for the Installation of Concentrated Solar Power in Northeast of Brazil Using Analytic Hierarchy Process (AHP)

Brazil has a predominantly renewable energy matrix, with large participation of water resource in domestic supply of energy. Data from 2019 National Energy Balance show that renewable sources (water, biomass, wind and solar photovoltaic) together represented 83% of domestic electric supply in 2018, where the remaining percentage (16.7%) represented non-renewable sources. The generation of electricity through thermal solar technology was not representative. However, it is known that Brazil presents high potential for the installation of solar thermal plants, especially in the Northeastern Region, where direct normal solar irradiation values are high. It is observed that the (high) costs of the projects associated to the absence of a specific incentive program make Concentrating Solar Power (CSP) plants installation more and more time consuming. As a way to contribute to the insertion of solar thermal energy in Brazil, this article presents a methodology for the location of parabolic trough solar thermal plants of 80 MW for the State of Bahia, located in the Northeastern Region of Brazil. Such methodology was based on the application the Analytic Hierarchy Process (AHP) method and the Geoprocessing Technologies to define potentially available sites for the implementation of the projects. For the analysis, parameters related to energy production in the solar power plant, electric, roadways and water infrastructure of the plant were taken into account, as well as the occupation, slopes and land use. Considering the analyses performed, it was confirmed that Bahia disposes of many sites with great generation potential, especially in the western region of the State (at Barreiras), where favorable conditions were found for the development of the technology. Localities situated in other region of the State were also confirmed as suitable, however with less site availability for the insertion of plants. Methodology validations were also carried out and indicated that the model reached the proposed objective, faithfully representing the real-world simplifications that were made.

Dynamic simulation and parametric influence analysis on thermal performance of a quartz tube solid particle receiver in solar tower power plants

Due to a higher operating temperature(≥800 ℃),Solar Particle Receiver(SPR)which uses particles as the working medium is considered as one of best candidates to improve the thermoelectric conversion efficiency of concentrating solar power plants.In this paper,a quartz tube solid particle receiver model is fully developed by using the discretized lumped parameter method,in which the calculation process of particle temperature and thermal loss is clearly given.In order to improve the manipulation level of particle receiver during the operation,the dynamic characteristics of the quartz tube particle receiver are comprehensively studied by the disturbance test of selected input parameters.Besides,in order to grasp the influence rule of key parameters on the thermal performance of particle receiver,the key parameters'sensitivity analysis is also deeply studied.The results show that the particle outlet temperature can reach as high as 810 ℃ under a relatively small value of solar flux 600 kW/m^(2),but the receiver efficiency is only about 75%;Besides,the receiver efficiency shows a variation tendency that it rises first falls afterwards with the increase of incident solar flux.The validity of proposed model is verified by a heating experi-mental system with a single quartz tube,and the relative error is not more than 7.9%.The research results are beneficial for understanding the dynamic characteristics and designing the particle receiver.

槽式光热装置承压特种设备损伤模式及检验检测难点分析

本文通过对槽式光热装置的工艺流程及生产特点进行分析,识别出装置存在的典型损伤模式有机械疲劳、热疲劳、熔盐腐蚀、低分子有机酸腐蚀和碱应力腐蚀开裂等。结合槽式光热装置的运行情况和承压设备特点,发现检验检测过程中存在导热油管道长期高温运行无法停机检验检测,核心设备存在多种疲劳损伤模式检验检测要求高及安全评价难等行业难点问题,为保障光热发电领域特种设备安全,亟须加强科技攻关予以解决。

考虑REGS和可调热电比的综合能源系统优化调度

在“双碳”目标背景下,针对热电联产机组“以热定电”模式导致的弃风问题,文章提出了一种考虑可再生增强型地热系统(Regenerative Enhanced Geothermal System,REGS)和可调热电比的综合能源系统(Integrated Energy System,IES)优化调度模型。首先,构建干热岩提取循环等模型,分析了能量分配系数对于REGS作为源端的热电可调节机理;其次,研究了REGS配合光热电站和热电联产机组耦合运行机制,分析了耦合运行改善热电比的机理,并引入广义机组热电比控制模型;再次,以购能成本、运行成本、运维成本、弃风成本及碳税成本之和最小构建目标函数进行优化求解;最后,利用西北某地区实际数据进行算例分析,验证了所提模型能够提高系统经济性和风电消纳率,减少碳排放。

光热电站熔盐储罐热应力分析

基于光热电站熔盐储罐结构建立了储罐的三维计算模型,通过载荷施加及边界条件设置进行热应力耦合分析,得到不同斜温层位置储罐的热应力及位移分布情况。根据不同斜温层厚度、位置获得储罐罐壁热应力变化趋势。斜温层厚度越大,储罐罐壁热应力越小。斜温层位置由罐底上升到罐顶,罐壁热应力先增大后减小。这些结果不仅有助于深入了解储罐的工作性能和安全性,还为储罐的优化设计和改进提供了重要的理论依据和实践指导。

核电厂磷酸铁锂蓄电池热老化鉴定研究

参考某核电厂磷酸铁锂蓄电池系统预期使用场景,设计了大容量磷酸铁锂蓄电池热加速老化模型和热加速老化流程。选取三组蓄电池作为试验对象,分别开展了25℃、45℃和60℃下的热加速老化试验。通过数据分析,发现该蓄电池容量衰减率与储存时间的0.5次方呈线性变化规律。通过ln(c)~1/T的线性回归分析,得到了该蓄电池的活化能相关参数。进一步分析发现,该蓄电池在60℃下试验18.7天可等效在25℃下存储1年的规律。该研究成果可用于指导核电厂开展大容量磷酸铁锂蓄电池加速热老化试验。

光-风电协同的低碳综合能源生产单元优化模型

为提升可再生能源发电并网消纳水平,协助传统燃煤电厂低碳化改造,推动电力系统低碳能源转型,以周孝信院士提出的综合能源生产单元架构为基础,建立光-风电协同的低碳综合能源生产单元优化模型,利用光热电站和风力发电为碳捕集系统稳定供能,减少碳捕集过程中消耗的燃煤资源。结果表明,与传统模型相比,光-风电协同的低碳综合能源生产单元优化模型将系统运行成本降低了9.6%,碳排放量降低了11.7%,产品收益提高了80.4%,具有良好的经济性与低碳性。

Comprehensive Review of Line-Focus Concentrating Solar Thermal Technologies: Parabolic Trough Collector (PTC) vs Linear Fresnel Reflector (LFR)

In the present review,parabolic trough collector(PTC)and linear Fresnel reflector(LFR)are comprehensively and comparatively reviewed in terms of historical background,technological features,recent advancement,economic analysis and application areas.It is found that although PTC and LFR are both classified as mainstream line-focus concentrating solar thermal(CST)technologies,they are now standing at different stages of development and facing their individual opportunities and challenges.For PTC,the development is commercially mature with steady and reliable performance;therefore,extension of application is the main future demand.For LFR,the development is still in rapid progress to commercial maturity,yet indicating very promising potentials with high flexibility in novel designs and remarkable reduction in capital and operational costs.The question,which has to be answered in order to estimate the future perspectives of these two line-focus CST technologies,becomes which of these characteristics carries more weight or how to reach an optimal trade-off between them.

Toward Implementing HH the Amir Declaration of 2% Electricity Generation by Solar Energy in 2020

The utility solar power plants were reviewed and classified by two basic groups: direct thermal concentrating solar power (CSP) and photovoltaic (PV). CSP as Parabolic Trough Collector (PTC) of 100 MW solar power plants (SPP) is suggested and suitable to provide solar thermal power for Qatar. Although, LFC had enough experience for small projects, it is still need to work in large scale plant such as 100 MW and couple with multi effect distillation (MED) to confirm costs.

不同瞄准策略的线性菲涅耳式聚光器光学性能

吸热管表面能流密度分布的均匀性对线性菲涅耳式聚光器的光热性能及安全运行有着重要影响。基于Tonatiuh光学仿真软件构建了线性菲涅耳式聚光器模型,研究了圆柱面形反射镜焦距及瞄准点位置与光斑宽度之间的关系,在此基础上探讨了不同瞄准策略下线性菲涅耳式聚光器的光学效率及能流分布的均匀性。结果表明:采用瞄准点均匀分布的瞄准策略,聚光器在保持较高光学效率的同时能够提升集热管表面能流分布的均匀性。采用优化后的瞄准策略,线性菲涅耳式聚光器光学效率可达到87.4%,集热管表面能流密度标准差由45.3%降低到30.7%,集热管顶部能流密度提升了10.2%。集热管空管预热采用该优化瞄准策略,在变占空比跟踪模式下,集热管弯曲变形程度远小于现有瞄准策略。该结果可为线性菲涅耳式聚光集热系统的优化设计提供理论支撑。

基于设备互补特性的冷热电系统优化

为提高能源系统综合性能,将地源热泵、光伏和光热等可再生能源集成于以原动机为核心的冷热电系统,并着重对系统设备的效率进行研究。基于设备能量互补特性,提出优化多个设备运行参数,分别是地源热泵供冷启动因子和供热启动因子以及原动机的启动因子来实现整个系统设备效率的提高。将控制多个设备的启动因子结合以电定热运行模式与传统以电定热运行模式进行对比分析,并以单独的地源热泵系统为参考系统,采用黑洞算法对系统进行优化。研究结果表明,与传统模式相比,控制多个启动因子模式系统具有更好的性能。与参考系统相比,耦合可再生能源的冷热电系统性能指标有了较大改善,特别是以启动因子模式运行(年能源节约率达到36.03%;年CO_(2)减排率达到53.24%;年总成本降低率达到36.85%;年综合性能达到42.04%)。

太阳能热发电系统多模型加权预测控制研究

针对太阳能热发电过程中广泛存在的随机性和不确定性问题,文中采集实测的数据进行聚类后建立多模型,设计了多模型加权预测控制器.首先,采用模糊聚类算法对实测的太阳能热发电数据进行分类,再用递推最小二乘法建立系统的多模型作为预测模型;其次,取集热器入口温度、太阳辐照强度以及环境温度为扰动信号,以导热熔盐的流速为控制量控制集热器的出口温度,并针对不同的子模型设计预测控制器;第三,按照子控制器的加权策略得到最小的控制增量并对系统进行稳定性分析;最后,进行试验仿真分析,和目前多采用的单模型预测控制结果比较,加权多模型预测控制精度更高,滞后时间更短.

浅谈太阳能热发电厂厂区管线综合布置

通过对一些太阳能热发电厂管线综合布置工程实践和国内外有关资料的研究,分析厂区管线综合布置中重点考虑的因素,分别针对塔式和槽式太阳能热发电厂的发电区和集热场,提出主要管廊分布和规划原则,进一步阐述太阳能热发电厂厂区特有的主要管线布置和敷设的具体要求,以达到满足工艺流程、节约用地、减少项目投资、方便施工维护的目的。

Design and optimization of CSP power plants for Pakistan:a comparative study

Despite having very high solar irradiance,Pakistan still does not have any installed concentrated solar power(CSP)plant.Several studies have shown that multiple locations within the country are suitable for CSP plants,but there is limited availability of comprehensive comparative studies.Therefore,this article presents a comparative analysis of different CSP technologies in Pakistan,focusing on their potential to address the country’s energy crisis.The study evaluates the pros and cons of different CSP technologies at various locations through site assessment,modelling,optimization and economic analysis using the System Advisor Model.Quetta and Nawabshah were selected as the locations for modelling multiple scenarios of 100-MW plants,using central receiver systems,parabolic trough collectors and linear Fresnel reflectors.The plants were integrated with thermal energy storage and the storage capacity was optimized using parametric analysis.The results showed that a central receiver system for the location of Quetta was the most favourable option,with an annual energy yield of 622 GWh at 7.44 cents/kWh,followed by a central receiver system for Nawabshah(608 GWh,9.03 cents/kWh).This study is the first to show that switching between line-concentrated and point-concentrated CSP technologies can open new opportunities for sites in Pakistan with relatively high solar resources,resulting in a 21.3%reduction in the levelized cost.

塔式太阳能光热电站发电区总平面布置及优化

文章选取国外13个、国内8个已建成的塔式太阳能光热电站和近两年正在前期阶段或正在实施的6个国内项目,利用跨平台地图浏览软件进行塔式光热电站发电区总平面布置及优化研究。针对发电区呈圆形布置造成的局部空地较多的问题,采用“切一刀”的方式进行初步优化,采用“切几刀”的方式进行深度优化,使得塔式太阳能光热电站发电区平面布置更为合理、紧凑,功能分区明确,工艺流程更加顺畅,土石方量和工艺管线短截,从而达到节约用地、节省项目投资的效果。