Concentrated solar thermal power generation is becoming a very attractive renewable energy production system among all the different renewable options, as it has have a better potential for ...dispatchability. This dispatchability is inevitably linked with an efficient and cost-effective thermal storage system. Thus, of all components, thermal storage is a key one. However, it is also one of the less developed. Only a few plants in the world have tested high temperature thermal energy storage systems. In this paper, the different storage concepts are reviewed and classified. All materials considered in literature or plants are listed. And finally, modellization of such systems is reviewed.
This work investigated the prediction of the optimum height and tilt angle of the solar receiver of a 30kWe solar tower power plant for the electricity production in the Sahelian zone. Initially, the ...solar field is sized to determine the total reflecting surface area of the mirrors and the number of heliostats. A PS10-like radially staggered heliostat field is used to design the heliostat layout in the field using a Matlab code. The concentrated solar flux at the input of the receiver was determined using Soltrace software by the Monte Carlo ray tracing (MCRT) method. The sizing results show that the total reflecting surface area is 350msup.2 for an optical efficiency of 76.4% and a reference DNI of 600W/msup.2. The solar field layout indicates 175 heliostats of 2msup.2 surface area and 1.5m height each. The simulation results show that the optimum height and tilt angle of the solar receiver are 26m and 65°, respectively.
Power generation systems are attracting a lot of interest from researchers and companies. Storage is becoming a component with high importance to ensure system reliability and economic profitability. ...A few experiences of storage components have taken place until the moment in solar power plants, most of them as research initiatives. In this paper, real experiences with active storage systems and passive storage systems are compiled, giving detailed information of advantages and disadvantages of each one. Also, a summary of different technologies and materials used in solar power plants with thermal storage systems existing in the world is presented.
To compete with conventional heat-to-power technologies, such as thermal power plants, Concentrated Solar Power (CSP) must meet the electricity demand round the clock even if the sun is not shining. ...Thermal energy storage (TES) is able to fulfil this need by storing heat, providing a continuous supply of heat over day and night for power generation. As a result, TES has been identified as a key enabling technology to increase the current level of solar energy utilisation, thus allowing CSP to become highly dispatchable. This article aims to review different TES technologies that have been investigated and deployed over the past two decades. The review will give a comprehensive overview of TES technologies investigated, demonstrated and/or deployed in CSP plants with a specific emphasis on TES materials perspective. A thorough analysis will also be given on the state-of-the-art of the CSP technologies including commercial development and research innovation. An attempt is also made to use the information gathered along this review to postulate future technology evolution of CSP plants in terms of CSP configurations, TES technologies and location of CSP plants, and to assess the current and future role of TES in CSP field.
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•Thermal energy storage is a key enable technology to increase the CSP installed capacity levels in the world.•The two-tank molten salt configuration is the preferred storage technology, especially in parabolic trough and solar tower.•By 2020, the plants without storage will be just 30% of the total installed capacity.•Molten salt technology will be used in the 67% of the plants, followed by concrete, steam and packed bed.•To increase TES deployement level, diversified alternatives must be found, specific for each CSP configuration requirements.
•The performance of CSP and PV plants were compared with similar assumptions.•The influence of the site on the performance of CSP and PV plants is determined.•CSP plants performance is always higher ...in locations where DNI is prevailing.•CSP levelized electricity costs are generally lower than those from PV plants.•PV plants may produce larger amounts of electricity where the DNI is not prevailing.
Solar energy is a source, which can be exploited in two main ways to generate power: direct conversion into electric energy using photovoltaic panels and by means of a thermodynamic cycle. In both cases the amount of energy, which can be converted, is changing daily and seasonally, causing a discontinuous electricity production. In order to limit this drawback, concentrated solar power plants (CSP) and photovoltaic plants (PV) can be equipped with a storage system that can be configured not only for covering peak-loads but also for the base-load after the sunset or before the sunrise. In CSP plants it is the sun’s thermal energy to be stored, whereas in PV applications it is the electrical energy to be stored in batteries, although this is not economically and environmentally feasible in large-scale power plants.
The main aim of this paper is to study the performance of concentrated solar power plants equipped with molten salts thermal storage to cover a base load of 3MWel. In order to verify the possibility of storing effectively the thermal energy and to design a plant for base load operation, two locations were chosen for the study: Gela in southern Italy, and Luxor in Egypt. The electricity production of the CSP facilities has been analyzed and then compared with the electricity production of PV plants. Two different comparisons were done, one by sizing the PV plant to provide the same peak power and one using the same collectors surface. This paper has also highlighted some important issues in site selection and in design criteria for CSP plants used for base load operation.
The high variability of the direct normal radiation during the year in southern Italy may cause several problems in CSP facilities, mainly related to the wide range of energy input from the sun. The more uniform and higher values of the solar radiation in the Egyptian location mitigates this problem and allows achieving higher efficiencies than in southern Italy. In most cases the electricity produced by the CSP plant is higher than that produced by a similar PV plant, because the presence of the storage system guarantees the continuity of electricity production even without solar radiation. An economic analysis based on the estimation of the levelized electricity cost (LEC) for both CSP and PV power plants located both in south of Italy and Egypt was carried out in order to investigate which is the most cost effective solution. In all the cases considered, the CSP facilities resulted the best option in terms of cost of electricity produced due to the continuity of energy production during the night hours.
Identifying potential locations for installation of solar power plants is a critical step in utilizing sustainable energy resources. In this study, a GIS-based Multi-Criteria Decision Analysis ...(GIS-MCDA) technique is used to generate maps that represent potential areas for solar power plants in four provinces with different climate conditions in Iran. The concept of risk is included in the GIS-MCDA process using the Ordered Weighted Averaging (OWA) model. The OWA model can provide various risk-taking (optimistic) and risk-aversion (pessimistic) scenarios to determine the suitable power plant areas. The results of this study indicate that provinces located in an arid climate such as Yazd contain a more suitable area for the solar power plants compared to wet climate provinces (e.g., Mazandaran). The sensitivity analysis of results show that the criterion “fault” has the minimum effect while the criteria “slope” and “road network” have the maximum effects on the area of the highly desirable class.
•The GIS-MCDA is used to evaluate the locations for establishment of solar power plants.•The evaluation process involves the locations in different climate conditions.•An OWA-based technique is utilized to incorporate risk in solar energy assessment.•The sensitivity of results to each criterion is evaluated.
Solar Chimney Power Plants: Numerical Investigations and Experimental Validation summarizes the effect of the geometrical parameters of a solar chimney on the airflow behavior inside a solar chimney ...power plant. Chapters in this experimental handbook are presented in two parts with the goal of equipping readers with the information necessary to study and determine key factors which affect the performance of the solar chimney power plant.In the first part, the authors present a simulation developed by using computational fluid dynamics (CFD) modeling software ANSYS Fluent to model the airflow. The adopted CFD models include k-ɛ turbulence model, the DO radiation model and the convection heat flux transfer model. These models have been validated with anterior experimental results.In the second part, the simulated models are then tested with alternate geometric configurations of the solar chimney power plant. The numerical studies allow readers to consider ways to expand on the design optimizing of the solar chimney when constructing a prototype. Geometrical parameters include the height, the diameter of the chimney and the dimensions of the solar collector and their effect on the temperature and air pressure is documented to validate models used for experimental simulations.The handbook also includes a study of an experimental prototype, constructed at ENIS. The researchers have gathered data on the environmental temperature, distribution of the temperature, air velocity and the power output generated by the turbine, the solar radiation and the gap of temperature in the collector of the prototype.
Concentrated solar power plants (CSPs) are gaining increasing interest, mostly as parabolic trough collectors (PTC) or solar tower collectors (STC). Notwithstanding CSP benefits, the daily and ...monthly variation of the solar irradiation flux is a main drawback. Despite the approximate match between hours of the day where solar radiation and energy demand peak, CSPs experience short term variations on cloudy days and cannot provide energy during night hours unless incorporating thermal energy storage (TES) and/or backup systems (BS) to operate continuously. To determine the optimum design and operation of the CSP throughout the year, whilst defining the required TES and/or BS, an accurate estimation of the daily solar irradiation is needed. Local solar irradiation data are mostly only available as monthly averages, and a predictive conversion into hourly data and direct irradiation is needed to provide a more accurate input into the CSP design. The paper (i) briefly reviews CSP technologies and STC advantages; (ii) presents a methodology to predict hourly beam (direct) irradiation from available monthly averages, based upon combined previous literature findings and available meteorological data; (iii) illustrates predictions for different selected STC locations; and finally (iv) describes the use of the predictions in simulating the required plant configuration of an optimum STC.
The methodology and results demonstrate the potential of CSPs in general, whilst also defining the design background of STC plants.
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