碟式太阳能发电在分布式能源系统中的应用

碟式太阳能发电系统具有单机容量小,排布灵活,余热可综合利用等特点,是一种较适合与分布式能源系统结合的太阳能利用类型。对碟式太阳能发电技术进行逐一分析,总结了在分布式能源站中应用碟式太阳能所面临的诸多问题。结合实例,详细介绍华电电力科学研究院有限公司一套25 kW的碟式太阳能发电系统运行情况,提出系统的改进和提升方向。     

碟式斯特林太阳能热发电技术及发展趋势

能源与环境的突出矛盾,给太阳能热发电产业带来了新的契机。本文立足于碟式斯特林热发电技术,简要介绍碟式系统的关键技术及国内外的研究成果,并对这种具有发展潜力的太阳能热发电技术进行分析,最后基于当前能源领域和研发现状,指出了我国太阳能热发电行业面临的问题和挑战,提出其广阔的发展前景。     

太阳能热发电系统的研究开发现状

太阳能热发电是一种很有发展前景的大规模太阳能利用技术。介绍和分析了国内外塔式、槽式、碟式等太阳能热发电技术的研究状况,分析了这些技术的优缺点以及一些改进方案。结合我国国情,指出了我国太阳能热发电所面临的问题及挑战;根据我国可再生能源发展规划,分析了我国太阳能热发电技术的发展前景。     

碟式斯特林太阳能热发电的技术发展

碟式斯特林太阳能热发电是目前发电效率最高的太阳能热发电的技术.介绍了碟式斯特林太阳能热发电系统原理,论述了国际上目前以热气机为核心技术的碟式太阳能热发电系统发展状况.指出我国的燃气热气机发电技术已经取得了突破性的发展,25 kW级碟式斯特林太阳能热发电系统的研发已具备了技术基础.     

碟式斯特林太阳能发电系统最新进展

太阳能热发电技术中最具发展潜力的是碟式太阳能高温发电技术,尤其是近几年碟式斯特林太阳能发电技术更是令世界瞩目,它具有光电转换效率高、耗水量低、发电方式灵活及可逐步规模化等特点。目前,国内外碟式斯特林太阳能发电系统的研制方兴未艾,国外太阳能斯特林发电机制作及测试技术已趋于成熟,正处于中试和大规模推广阶段。国外主要的碟式斯特林发电系统包括SES公司的SunCatcher单元、Cleanergy公司的Eurodish单元、Infinia公司的PowerDish单元等。国内碟式斯特林太阳能热发电技术研究取得了一些成绩,但总体来说,目前还未获得实质性的进展,相关研究尚处于初级阶段。碟式斯特林太阳能发电系统的核心部件是太阳能斯特林发电机,其某些关键部件的研发难度较大,如高温太阳能吸收器、高效回热器、工质密封、功率和转速控制等。要攻克这些关键技术,需要国内外相关部门的大力支持。我国科研工作者应通过各种形式与国外斯特林发电机制造商及科研机构进行技术合作,逐渐掌握此项技术;或者借鉴国外的研制经验自主研发,然后通过示范推广,建设大型碟式斯特林太阳能发电厂。     

太阳能光热发电技术发展现状

介绍太阳能光热发电技术系统：塔式、槽式和碟式3种太阳能光热发电系统,对各类太阳能光热发电技术与常规发电技术进行分析对比,阐述3种太阳能光热发电技术的发展现状及其存在的问题,说明太阳能光热发电具有的广阔应用前景。     

碟式聚光太阳热发电技术

太阳热发电技术是利用太阳集热器把太阳能聚集起来,将工质加热到一定的温度,驱动热机带动发电机发电。由于整个系统的热源来自太阳能,所以称为太阳热发电技术。太阳能热发电系统一般由聚光系统、集热系统、热传输系统、蓄热贮能系统、热机系统等组成。当前太阳热发电技术主要有以下5种:(1)中央塔式(2)槽式(3)单碟独立电站和碟群体系(4)太阳烟囱(5)太阳池。本文通过介绍国外碟式太阳热发电技术的现状及发展趋势,提出发展我国碟式热发电技术的建议与思考。1碟式太阳热发电技术的历史与现状a.碟式热发电系统现代碟式太阳能热发电技术在20世纪70…     

太阳能热发电技术与系统

我国对大规模太阳能热发电技术的研究仍处于起步阶段,而国外则已进行了多年的研究.本文介绍了各类太阳能热发电技术及其系统,总结了国内外一些学者的研究成果,比较了各类太阳能热发电技术的优缺点.塔式和槽式技术最适用于大规模太阳能热系统.碟式太阳能热发电装置功率较小,适用于分布式能源系统.其它太阳能热发电技术仍处在试验研究阶段.今后的研究重点主要是塔式太阳能热发电系统的系统集成技术和槽式真空吸热管技术.     

基于小型发电机的碟式太阳能热发电技术研究进展

阐述了碟式太阳能热发电系统的发展历程和特点，介绍了碟式热发电的基本原理，着重分析了碟式热发电所涉及的关键技术，包括Stirling发电机、Brayton发电机、碟式聚光镜和受热器。通过对关键技术的分析，指出提高碟式聚光镜系统的稳定性和降低成本两个方面是当前技术开发的重点。同时提出了发展中国碟式太阳能热力发电技术所需技术开发过程的建议。     

对我国发展太阳能热发电的一点看法

太阳能热发电是大规模开发利用太阳能的一个重要技术途径。由于关键技术有待重大突破,目前国外塔式、槽式、碟式系统都还面临着投资大、成本高的问题。本文分析了塔式、槽式、碟式现行三种技术路线在我国推广应用的技术难点,提出了一个新型分立式太阳能热发电技术路线。这项新技术建立在太阳聚光跟踪理论突破的基础之上,不仅具有完全自主知识产权,而且比国外现行的热发电技术更为经济高效。     

碟式斯特林发动机的研究进展

太阳能的利用和斯特林发动机的研发符合目前解决全球能源危机问题的需要。对斯特林热机的发展过程和循环工作原理进行了总结,综述了国内外对于碟式斯特林发电技术的应用现状,归纳了碟式斯特林发电系统中太阳光跟踪控制系统、接收器聚热技术、斯特林发动机功率控制技术和斯特林发动机密封技术等关键技术的研究成果和应用现状,总结并展望了碟式斯特林发电技术的发展重心,为进一步的研究工作提供参考。     

Techno-economic appraisal of a dish/stirling solar power plant in Greece based on an innovative solar concentrator formed by elastic film

As the environmental problems caused by the use of conventional fuels have risen significantly and due to the increase in fossil fuel prices, the importance of reducing society dependence on non-renewable energy sources becomes more and more urgent. It is clear that this could only happen by switching to extensive use of clean energy sources such as renewable energy sources. In this paper a technical feasibility and economic viability study of a dish/Stirling solar power plant in Greece is presented. The proposed power plant uses Dish/Stirling technology and has nominal power 10 MW. The proposed solar concentrator system consists of a primary mirror, formed by elastic film, used to focus the sun's rays onto a secondary mirror which then deviates this radiation into the receiver (Stirling engine). TRNSYS program was developed to simulate Dish/Stirling power plant operation in order to investigate its performance in Greece. The simulation predicted that the proposed power plant could produce 11.19 GWh annually. Project investment cost is approximately 27,000,000 €, while payback is achieved after 16 years of operation. The total profit at the end of the analysis period of 25 years is estimated to be 25,500,000 €.     

Technical and economical evaluation of solar thermal power generation

This article presents a feasibilty on a solar power system based on the Stirling dish (SD) technology, reviews and compares the available Stirling engines in the perspective of a solar Stirling system.The system is evaluated, as a parameter to alleviate the energy system of the Cretan island while taking care of the CO₂ emissions. In the results a sensitivity analysis was implemented, as well as a comparison with conventional power systems.In the long-term, solar thermal power stations based on a SD can become a competitive option on the electricity market, if a concerted programme capable of building the forces of industry, finance, insurance and other decision makers will support the market extension for this promising technology.     

Environmental evaluation of dish-Stirling technology for power generation

Dish-Stirling technology for power generation (Stirling engine driven by renewable energy, such as solar) is a promising development in electricity generation. The efficiency value, approximately 30% of normal direct solar radiation converted to electricity (Romero, 2010), is the highest among other solar energy generation systems. In the comparison against other solar energy exploitation alternatives, the environmental evaluation of the dish-Stirling technology must be taken into account. The aim of this paper is to provide a comparative environmental assessment of a dish-Stirling technology with respect to a similar photovoltaic facility. The Life Cycle Assessment procedure has been applied, and the results have been analysed in terms of CO₂-equivalent emissions as well as using two impact evaluation methods: Eco-indicator 99 and CML2. The results show that the level of environmental impacts is similar for both technologies.     

Low pressure solar thermal converter

The current development of solar power converters with air as working fluid focuses mostly on concentrating collectors combined with hot-air engines, and on very low temperature solar tower concepts. Whilst concentrating collectors and Stirling engines need complex technology, solar tower converters have very low efficiencies and require large installations. Pressurized containers as energy converters offer the advantage of simplicity, but appear not to have been investigated in detail. In order to assess their performance potential, an idealised thermal pressure converter was analysed theoretically. Two improvements to increase the initially low efficiency derived from theory were found. Neglecting losses, maximum theoretical efficiencies ranged from 6.7% for a temperature difference of 60 K to 17.7% for a difference of 195 K. The low pressure solar thermal converter appears to offer development potential for low-tech solar energy conversion.     

Introducing an integrated SOFC,linear Fresnel solar field,Stirling engine and steam turbine combined cooling,heating and power process

A new integrated combined cooling, heating and power system which includes a solid oxide fuel cell, Stirling engine, steam turbine, linear Fresnel solar field and double effect absorption chiller is introduced and investigated from energy, exergy and thermodynamic viewpoints. In this process, produced electrical power by the fuel cell and steam turbines is 6971.8 kW. Stirling engine uses fuel cell waste heat and produces 656 kW power. In addition, absorption chiller is driven by waste heat of the Stirling engine and generates 2118.8 kW of cooling load. Linear Fresnel solar field produces 961.7 kW of thermal power as a heat exchanger. The results indicate that, electrical, energy and exergy efficiencies and total exergy destruction of the proposed system are 49.7%, 67.5%, 55.6% and 12560 kW, respectively. Finally, sensitivity analysis to investigate effect of the different parameters such as flow rate of inputs, outlet pressure of the components and temperature changes of the solar system on the hybrid system performance is also done.     

Analysis and design consideration of mean temperature differential Stirling engine for solar application

This article presents a technical innovation, study of solar power system based on the Stirling dish (SD) technology and design considerations to be taken in designing of a mean temperature differential Stirling engine for solar application. The target power source will be solar dish/Stirling with average concentration ratio, which will supply a constant source temperature of 320 °C. Hence, the system design is based on a temperature difference of 300 °C, assuming that the sink is kept at 20 °C. During the preliminary design stage, the critical parameters of the engine design are determined according to the dynamic model with losses energy and pressure drop in heat exchangers was used during the design optimisation stage in order to establish a complete analytical model for the engine. The heat exchangers are designed to be of high effectiveness and low pressure-drop. Upon optimisation, for given value of difference temperature, operating frequency and dead volume there is a definite optimal value of swept volume at which the power is a maximum. The optimal swept volume of 75 cm³ for operating frequency 75 Hz with the power is 250 W and the dead volume is of 370 cm³.     

Progress in beam-down solar concentrating systems

Concentrating solar technologies are promising renewable energy systems for exploiting incident beam solar irradiation with high exergy efficiency values. These systems provide the possibility for producing useful heat at high temperatures that can be utilized by highly efficient power cycles or producing directly solar fuels with receiver reactor technology. In the last years, the concept of beam-down concentrating solar technology gains more and more attention due to a series of advantages associated with this idea. This concept is based on the use of two-stage reflectors for concentrating solar irradiation close to the ground, something that leads to a more compact system with reduced height. Furthermore, the high-temperature heat production and the chemical processes take place on the ground and not at a great height, increasing the safety levels of the system. Moreover, this design leads to compact configurations with lower materials use, lower wind loads and without the need to move the receiver for tracking the sun.The objective of this review is to present the recent progress on beam-down solar concentrating technology and to highlight the need for giving attention to this direction. Critical advantages of this technology are demonstrated and the associated limitations are discussed. The emphasis is on the presentation of the different technologies that can be coupled with the beam-down technology. Thermodynamic power cycles (Brayton, Rankine and Stirling), photovoltaics, thermochemical processes, as well as other applications are included and discussed. Practically, power production and solar fuels are the major useful outputs that can be generated by beam-down solar concentrating configurations. The reviewed technologies are critically discussed and compared in terms of energy, economic and environmental aspects. Future steps in the field are suggested based on the existing literature.     

Competitive solar heat engines

This article presents a technical innovation consisting of replacing the piston–cylinder system by metallic bellows in free-displacer Stirling engines. It deals with the advantage of heat engines of low power, integrating this innovation with plane solar collectors. A theoretical study requiring notions of finite time thermodynamics determines the optimised dimensioning of such systems and makes them appear serious competitors, on the one hand to solar cells to exploit solar energy and, on the other hand, to power stations regarding kW h unit cost.