Solar Parabolic Dish Concentrator Research Articles

Experimental study of the energy and exergy performance of a solar parabolic dish concentrator integrated with thermal energy storage

Concentrating solar power is rapidly becoming a mainstay of solar energy systems, with the parabolic dish concentrator being a common and high-performing option for medium-temperature applications. This study investigates the thermal performance of a parabolic dish concentrator integrated with phase change material based thermal energy storage. Energy and exergy efficiencies are compared for a water-based storage tank in thermosyphon circulation mode, both with and without phase change materials encapsulation. Various phase change materials capsules were strategically positioned within the tank in a certain position, which satisfies the melting temperature of the studied phase change materials. Steam generation was also measured and correlated with solar irradiation intensity. This study aims to address the changes in energy and exergy efficiencies for the system integrated with latent heat storage encapsulation. Results show the highest overall energy efficiency 46.7% was achieved with copper cylindrical capsules, while the base case without phase change materials yielded the highest overall exergy efficiency 5.23%, closely followed by the copper cylindrical capsule 4.94%. Peak energy and exergy efficiencies reached 79.37% and 11.12%, respectively. The copper cylindrical capsules provided the optimal balance between thermal and storage performance without compromising efficiency.

Energy optimization of parabolic dish solar concentrator coupled to organic Rankine cycle: Experimental and analytical investigation of cavity receiver design and covering effects

Concentrated solar power (CSP) systems offer a promising solution for sustainable energy, but achieving high and stable efficiency requires careful design optimization. This study evaluated the overall performance of a parabolic dish solar concentrator coupled to an Organic Rankine Cycle (ORC) system through experimental and analytical assessments. The research examined the impact of cavity receiver shape (cylindrical vs. spherical) and the use of a glass cover on thermal efficiency. Additionally, the effectiveness of a cone structure to reduce spillage losses and improve optical efficiency was explored. Testing showed a significant improvement in system performance, with an increase from 75 % for the open cavity to 90 % for the sealed cavity equipped with the cone structure (15 % increase). This highlights the importance of receiver design in reducing heat loss. To further optimize the system, a numerical model was developed and validated against experimental measurements. The simulation demonstrated that the overall system performance is significantly influenced by the water outlet temperature from the cavity receiver and the pressure drop within it. The model suggests that overall performance could be enhanced from 4.6 % to higher than 6 % by optimizing factors like water mass flow rate, cavity tube diameter, and the selection of a more suitable ORC working fluid (e.g., R245fa instead of R134a).

A new design for a built-in hybrid energy system, parabolic dish solar concentrator and bioenergy (PDSC/BG): A case study – Libya

This research aims to promote the sustainable utilization of locally available, environmentally friendly resources, making a substantial contribution to both mitigating global warming and fulfilling future energy needs. Hybrid renewable energy systems have demonstrated superior stability and reliability compared to single-source systems, all while operating at minimal costs. This paper provides an overview of various hybrid renewable energy systems employed for electricity generation. It underscores that in hot regions, despite high solar radiation, solar PV systems experience reduced electrical yield due to elevated solar cell temperatures beyond the recommended range, especially in summer. In such areas, leveraging solar thermal applications and abundant biomass energy from extensive agricultural activities is preferable. What sets this study apart is its innovative approach: replacing conventional hybrid systems, like PV, wind, diesel generators, and batteries, with a Stirling engine powered by dish solar concentrators, which offer high efficiency and cost-effectiveness. The proposed Hybrid Renewable Energy System (HRES), consisting of a parabolic dish solar concentrator and Biomass Digester (PDSC/BG), transforms challenges into opportunities. It provides the community with a sustainable source of electricity, heating, and cooking gas, simultaneously addressing the region's waste management issues. The system is evaluated at Brack City, Libya, and comprises a 36,560 m3 biomass digester that produces 27 Mm3 annually, a 1230 kW Stirling generator, and a 6006 m2 PDSC collector area. The system will add 5,670,534 kWh of energy to the grid yearly, with a peak load capacity of 1230 kWh and a coverage of 5,892,666 kWh. The system's technical and economical viability is evaluated using SAM software. The project has a 20.04-year payback period, an estimated capital cost of $12,365,896, and an LCOE of $0.075/kWh. Annual CO2 emissions will be reduced by 7.8 kton as a result of the project.

Numerical investigation of heat transfer in spirally coiled corrugated pipes: Assessment of turbulence models

The Archimedean spiral coil made of a transversely corrugated pipe represents the radiant heat absorber of a parabolic dish solar concentrator. The main advantage of the considered design is the coupling of two passive methods for heat transfer enhancement: coiling the flow channel and changing the surface roughness. The aim of this numerical study is to assess the capability of RANS models of different complexity (realizable k-?, SST k-?, and RSM linear pressure-strain) to adequately represent the heat transfer phenomena in the considered complex flow geometry for wide ranges of Reynolds and Prandtl numbers. The obtained results indicate that the realizable k-? model with enhanced wall treatment is inadequate to simulate the heat transfer for all flow conditions, while both SST and RSM slightly overestimate experimental data in the turbulent region and are able to predict laminarisation at low Reynolds numbers. The SST model predictions are more accurate in the transitional and at the beginning of the turbulent region, irrespective of the curvature ratio. The RSM predictions are generally more accurate in the turbulent region. Numerically obtained circumferential distributions of local Nusselt number reveal that considered turbulence models are unable to completely anticipate the interactions between the complex flow in the basic section of the pipe and the vortex flow within the corrugations.

Optical and thermal investigation of hyperbolic cavity receiver with secondary reflector for solar parabolic dish collector

A hyperbolic-shaped cavity-type receiver with a second stage reflection for a 40 m2 solar parabolic dish concentrator (PDC) is presented in this paper,along with optical and thermal modeling. The receiver geometry and the secondary reflector complete the hyperbolic geometrical shape of the present receiver. This study aims to estimate heat losses owing to natural convection and radiation under influential parameters associated with solar parabolic dish system. Optical modeling has been performed with verified model using ASAP® 2013 V1R1. The optical simulations have been carried out for varying receiver height (h1), height of the secondary (h2) and diameter-to-total height ratios (d/h) of 0.5, 1, and 1.5 while keeping the diameter of the plane aperture of the receiver (d) constant. The optimum receiver geometry has been selected based on the performance in terms of optical efficiency. The maximum efficiency found is 91.72% for h1 = 0.75 m and d/h = 0.5 for the mounting distance of 4.21 m. The optimized shape is further studied to determine how the receiver absorptivity and the secondary reflector's reflectivity affect the optical performance. The absorptivity and reflectivity range from 0.86 to 0.94. Obtained optimum receiver geometry from the optical investigation is further analyzed to estimate the heat transfer rate. The thermal modeling is performed for 0°, 30°, 60°, and 90° orientations of the receiver in ANSYS Fluent 2020 R1. A comprehensive comparison among the available models has been reported and validated with well-established experimental data. This work has developed free convective Nusselt number correlation. It can be a valuable addition to the existing literature.

Performance evaluation and optimization of solar dish concentrator in the upper Egypt region

AbstractThe goal of this study is to optimize and examine the effect of different rim angles and focus lengths on the performance of a solar parabolic dish. To achieve these goals, a solar parabolic dish concentrator was constructed with different focus point positions and tested under the climatic conditions of the Upper Egypt region in Qena city, with the location of (Latitude: 26.16°, Longitude: 32.71°). The preliminary experimental days started on 18th and lasted on 20th of September 2022, and the tested rim angles were 70°, 80°, and 60°. The results showed that the performance of the proposed solar parabolic dish concentrator was enhanced when the rim angle was between 60° and 70°, otherwise, the performance was regressed when the rim angle was between 70° and 80°. To optimize the rim angle, another available rim angle was selected to increase the performance of the solar dish fixed at 65°, and this angle was tested on 21st of September 2022. The results demonstrated that the thermal efficiency of the solar parabolic dish with rim angle of 65° was higher than that of 70°, 80°, and 60°, and the recorded thermal efficiency reached up to 79.5%, 39.4%, 5.84%, and 28.4%, respectively, under the tested rim angles.

Design, Fabrication and Performance Evaluation of Hybrid Parabolic Dish Solar Concentrator for Cooking and Heating of Water

Design, Fabrication and Performance Evaluation of Hybrid Parabolic Dish Solar Concentrator for Cooking and Heating of Water

A novel solar disk chamber reactor for agricultural waste recycling and biochar production

The quality and properties of biochar are generally influenced by the nature of the raw materials and pyrolysis techniques. To assess the quality of sesame biochar production, a disc chamber reactor set on a solar parabolic dish concentrator was proposed as a modified slow pyrolysis technique. To evaluate the physicochemical characterizations of the produced biochar, two pyrolysis settings were used: 470 °C for 1 h (T1) and 440 °C for 2 h (T2) to produce biochar from sesame stalk feedstock (SS) using the proposed solar disk chamber reactor. Ash content, mass fraction of elements (C, H, and O%), pH, surface area, zeta potential, Fourier transform infrared (FTIR), and scanning electron microscope (SEM) were investigated. The results showed that the mass of T1 biochar decreased by 5% when compared to T2, while ash content, pH, fixed carbon, and volatile gases for both biochars were relatively close. The H/C and O/C molar ratios were below 1.00 and 0.4, respectively, indicating a loss of degradable polar contents and the formation of aromatic compounds. The surface area of T2 biochar was three times the surface area of T1, with the opposite trend in mean pore diameter. Two biochars showed the same FTIR peaks and SEM data, with small differences in their characteristics, demonstrating that pyrolysis time and temperature had a tight relationship. Both biochars showed approximately similar properties. The reactor’s efficiency is mainly affected by solar energy and atmospheric conditions during operation, which influence the average surface temperature. In Egypt, climatic conditions would be more favorable in the summer to improve the efficiency of parabolic solar dish concentrators for producing high-quality biochar.Graphical abstract

Design, modeling and solar tracking control for a novel parabolic dish solar concentrator

AbstractA novel parabolic dish solar concentrator based on the improved 3-RPS parallel manipulator to drive the reflective mirror facet is proposed and designed, which can not only automatically adjust the position and orientation of the reflective mirror facet but also have the advantages of independent drive, high stiffness and no cumulative error. Then, using the coordinate transformation matrixes of the novel parabolic dish solar tracking platform, the kinematics models of the 3-RPS parallel manipulators associated with the solar altitude and azimuth angles are established. The altitude and azimuth angles of the solar movement at the installation location are calculated according to the calculation formula of solar position. To solve the problem of too many telescopic rods of the 3-RPS parallel manipulator, a genetic algorithm is used to optimize the height of the concentrator’s center of mass. Then the ideal trajectory and attitude of each telescopic rod of the 3-RPS parallel manipulators at different times of the day can be obtained with the inverse kinematics. The particle swarm optimization (PSO)-proportional-integral-derivative (PID) controller, which uses PSO algorithm to tune PID parameters, is proposed for solar trajectory tracking of the novel parabolic dish solar concentrator. The visual simulation model of the parabolic dish system is established in Simscape Multibody, and the trajectory tracking control experiment is carried out. The experimental results show that the trajectory tracking error of the novel dish solar tracking platform can be within 2.6 mm by using the PSO-PID controller.

A simplified opto-thermal assessment and economic study of parabolic dish solar concentrator pondering on the receiver position induced uncertainties

This paper investigates the opto-thermal and economic assessment of low-cost solar parabolic dish concentrators (PDC), focusing on the receiver position-induced uncertainties. An optical model of the proposed PDC system is developed in Tonatiuh optical simulation tool. The optical analysis is conducted by the Monte Carlo Ray Tracing method for different vertical and horizontal positions of the PDC’s receiver. In addition, An experimental test rig based on a locally manufactured PDC with a low-cost reflecting surface made of aluminium reflector foil is developed to achieve the purpose of this work. A cavity receiver made of a cylindrical-cone brass tube is used and tested under different positions of the focal point of the PDC. The impact of the uncertainties on the performance of the proposed PDC is experimentally estimated. A relatively simple mathematical model is utilized to evaluate the thermal and exergy performance for the different positions of the cavity receiver. The results showed that the proposed PDC could generate hot water at temperatures 77 °C, 64 °C, and 55 °C for the three focal point positions, respectively. The collector efficiency of the PDC-cavity receiver system in the receiver position 1, 2, and 3 were 70.2%, 53.2%, and 24 % while the average values of exergy efficiency for the PDC at the receiver positions were 4.7%, 2.3%, and 0.93% respectively. This clearly shows the effect of the receiver positions on the performance of the parabolic dish solar concentrator and justifies the requirement of appropriate positioning of the receiver for the parabolic dishes.

Effect of the concentration ratio on the thermal performance of a conical cavity tube receiver for a solar parabolic dish concentrator system

The proper design of the parabolic dish concentrator system and the accurate selection of variable operating parameters are critical in solar energy conversion and utilization. This paper comprehensively studied the design, simulation, and experimental thermal performance of a conical cavity tube receiver for parabolic dish concentrators at various concentration ratios to maximize thermal efficiency. The receiver was examined at a temperature variation of 20–130 °C with water as the working medium under a flow rate of 0.45 L per minute. The experimental testing was performed at different concentration ratios of 10.38, 20.76, and 31.15. The conical receiver's average exergy efficiency and energy efficiency were estimated to be 8.16% and 65.81%, respectively, within the highest concentration ratio of 31.15. The difference in temperature of the heat transfer fluid at the intake and exit of the receiver has a similar variation pattern to the energy efficiency of the receiver. In addition, the parabolic dish concentrator system with a conical cavity copper tube receiver was designed and simulated using COMSOL Multiphysics® to obtain the temperature distribution of the receiver with different concentration ratios, flux distribution in the focus of the plan, and incident heat flux on the receiver surface for real reflectors. The simulation results were compared with the experimental results, and a satisfactory agreement was achieved. The findings from this study are helpful for further parabolic dish concentrator system design optimization. The results indicate that this lightweight, highly efficient, and low-cost solar receiver has the capacity to be utilized with a solar parabolic dish-type concentrating system for thermal processes.

Performance analysis of a novel solar cogeneration system for generating potable water and electricity

PurposeThe utilisation of renewable energy sources for generating electricity and potable water is one of the most sustainable approaches in the current scenario. Therefore, the current research aims to design and develop a novel co-generation system to address the electricity and potable water needs of rural areas.Design/methodology/approachThe cogeneration system mainly consists of a solar parabolic dish concentrator (SPDC) system with a concentrated photo-voltaic module at the receiver for electricity generation. It is further integrated with a low-temperature thermal desalination (LTTD) system for generating potable water. Also, a novel corn cob filtration system is introduced for the pre-treatment to reduce the salt content in seawater before circulating it into the receiver of the SPDC system. The designed novel co-generation system has been numerically and experimentally tested to analyse the performance at Karaikal, U.T. of Puducherry, India.FindingsBecause of the pre-treatment with a corn cob, the scale formation in the pipes of the SPDC system is significantly reduced, which enhances the efficiency of the system. It is observed that the conductivity, pH and TDS of seawater are reduced significantly after the pre-treatment by the corncob filtration system. Also, the integrated system is capable of generating 6–8 litres of potable water per day.Originality/valueThe integration of the corncob filtration system reduced the scaling formation compared to the general circulation of water in the hoses. Also, the integrated SPDC and LTTD systems are comparatively economical to generate higher yields of clean water than solar stills.

Prediction of focal image for solar parabolic dish concentrator with square facets-an analytical model.

Solar parabolic dish concentrator is one of the high-temperature applications of more than 400°C for thermal and electrical power generation. In the solar parabolic dish concentrator, the arrangement of reflectors over the surface area is the significant factor for effective concentration of solar radiation. Also, focal image is one of the most influencing parameters in the design of receiver. Among the various reflectors, the square-shaped reflectors (facets) are comparatively effective in converging the incoming radiations to attain better focal image. In this regard, an attempt has been made to predict the focal image diameter of a solar parabolic dish concentrator with a square facet of different influencing parameters using a novel mathematical model. The influencing parameters considered for the study are aperture diameter, rim angle, and facet length of the dish concentrator. Using the model, the focal image dimension and aperture area of a solar parabolic dish concentrator with square facets can be predicted accurately for efficient design of a solar parabolic dish collector system. Finally, the model is validated with the experimentally obtained focal image diameter. The current model is in good agreement with the experimental value, with a deviation of 8.84%. Hence, the proposed model can be used for the design of parabolic dish systems.

Development and thermal performance evaluation of solar parabolic dish based on fiber‐reinforced plastic

AbstractThis paper illustrates the design and fabrication of a 76° rim angle solar parabolic dish concentrator with low cost based on fiberglass‐reinforced for heating of heat transfer fluid using the hand layup process. Numerous advantages of fiberglass material include corrosion resistance, lightweight, design flexibility, quick installation time, and low cost makes it suitable for fabrication. The concave surface on which the reflective sheets are mounted is made to a high degree of perfection. The design process, as well as the complete fabrication process, are elaborately discussed in this article. The thermal efficiency of the newly constructed fiberglass‐reinforced solar parabolic dish concentrator was assessed by heating the heat transfer fluid in the conical cavity receiver, which was cycled from the sump via a gear pump and flexible stainless steel connecting pipes. The maximum value of heat transfer fluid temperature achieved was 194°C at the sump. The average thermal efficiency achieved for indoor heating at the sump was 17.42%, 17.16%, and 17.21%, respectively, during Experiments 1, 2, and 3. The results indicate that this system is acceptable for indoor cooking in the kitchen, as the system achieves temperatures between 150°C and 194°C.

Performance Evaluation of Spiral Coil Receiver for Thermal Steam Generation Using Optical and Thermal Analysis of Parabolic Dish Concentrator

Solar energy has been advocated as the substitute for depleting fossil fuels for thermal applications and electricity generation. The research was aimed at determining the performance evaluation of the spiral coil receiver for thermal steam generation using a parabolic concentrating system. The parabolic dish solar concentrator (PDSC) with a rim angle of450C, the focal length of 6.15 m, and an aperture area of 5.8 m2 were designed and constructed for the determination of the variables. The PDSC and spiral coil receiver were made of stainless-steel reflector sheet and copper tube pipe respectively. Since the PDSC is for high enthalpy steam generation, it can be used for hot water and cooking applications. A finite element stress analysis was carried out to determine the thermal and optical efficiency of the system under various weather conditions. The thermal efficiency and optical analysis of the system were determined and obtained to be 54.4%, and 48.6% respectively. The efficiency according to the finding depends on the optical properties of the materials involved, the geometry of the collector, and the various imperfections arising from the construction of the collector.

Solar parabolic dish collector for concentrated solar thermal systems: a review and recommendations.

Energy demand in the present scenario is rising to meet the increasing demands of energy usage. On the other hand, the use for renewable energy sources now becomes essential to mitigate the climate change as well as to reduce gradual depletion of fossil fuels. Among these renewable energy sources, solar energy particularly solar thermal systems have phenomenal scope in present and future research. In solar thermal systems, concentrators are used to extract the energy from solar irradiation and convert it into useful form. Among different types of solar concentrators, the parabolic dish solar concentrator is preferred as it has high efficiency, high power density, low maintenance, and potential for long durability. In this paper, a detailed review has been carried out on the design parameters like focal length, concentration ratio, and rim angle of the parabolic dish solar concentrator system for achieving higher overall efficiency. The effects of different geometrical shapes of receivers on the overall heat transfer rates are discussed in this paper. Conical shaped receiver is having high overall optical and thermal efficiency comparing with other shapes of receivers. This study also shows that how the thermal performance of the receiver gets enhanced by 10-13% using nanofluids in place of general heat transfer fluids. The paper highlights different models using ray-tracing method for estimation and evaluation of the solar irradiation distribution on the receiver surface. The empirical relations for the design of parabolic dish solar concentrator system are derived for estimating overall concentrator efficiency and heat available at the receiver are given in this review. From the literature, the thermal performance of the receiver affecting the overall performance of the system is observed. Thermal losses due to geometrical properties and ordination of the receiver are explained in the observation section.

Performance of two solar cooking storage pots using parabolic dish solar concentrators during solar and storage cooking periods with different heating loads

A comparative experimental study on the effect of different cooking loads for two solar cooking pots incorporated with different thermal energy storage (TES) materials is presented. The pots have cavities in their walls for placing TES materials and are designed to be used with parabolic solar cookers. One pot is filled with erythritol as the TES material in the cavity, while the cavity of the other pot is filled with sunflower oil as the TES material. During the solar cooking period, the storage pots are heated up with solar energy, and cooking occurs as well as storage of thermal energy in the cavities of the pots. During the storage cooking period, the pots are placed in wonderbag slow cookers for off-sunshine cooking using the stored heat in the cavities. Water and sunflower oil with masses of 0.5,1.0, 1.5, 2.0, and 2.5 kg, respectively, are used as the cooking loads during both solar and storage cooking periods. The effect of the load is evaluated in terms of storage and heat utilisation efficiencies. The storage efficiencies marginally increase with the increase in the load when water is used as the heating load. The sunflower oil pot shows slightly higher storage efficiencies (3.2–4.4%) compared to the erythritol pot (2.5–3.9%) with water as the cooking load. Storage efficiencies using sunflower oil as the cooking load show slightly greater values compared to when using water and follow no particular trend with the increase in the mass of the load. Heat utilisation efficiencies increase with the load for both storage cooking pots and both cooking fluids. However, water shows higher heat utilisation efficiencies (erythritol-13-49%, sunflower oil-17-46%) compared to sunflower oil (erythritol-9.2–19%, sunflower oil-9.4–28%) during the heat utilisation experiments. The erythritol storage pot shows higher heat utilisation efficiencies compared to the sunflower pot when using water as the heating fluid. However, when using sunflower oil as the heating fluid, the sunflower oil pot shows higher heat utilisation efficiencies.

Thermal analysis of modified conical cavity receiver for a paraboloidal dish collector system

ABSTRACT In a solar paraboloidal dish collector system, the receiver is critical for transforming converged solar flux to heat energy. A cavity receiver is the most common type of receiver, as it lowers heat loss. An experimental investigation is carried out in this article to evaluate the thermal performance of a novel cavity receiver for dish system under real direct solar environments. The performance of the modified conical cavity receiver under stagnation condition and with heat transfer fluid was studied experimentally. A solar parabolic dish concentrator of 1.83 m rim diameter and rim angle of 66° was used for the experimentation. For both cases, the experiments were carried out for two days. The highest stagnation temperature of 167.2°C was recorded with a direct irradiance of 803 W/m2, according to the data. For day average direct irradiance of 555 W/m2 and 663 W/m2, the receiver’s average thermal efficiency was found to be 53% and 69%, respectively. For 694 W/m2 direct irradiance, a maximum thermal efficiency of 75% was achieved. The thermal efficiency was shown to be significantly dependent on direct irradiation. According to the results of the experiments, the proposed modified conical cavity receiver is a viable solution for solar parabolic dish collector systems.

Novel designs of cavity receiver for a solar parabolic dish concentrator

To enhance the performance of a parabolic dish concentrator, it must achieve the maximum thermal performance of the receiver. Hence the optimization of the receiver performance will play an essential role in optimizing the system of solar parabolic dish concentrator. Lot of studies investigated many configurations and designs for receivers and compared the performance among them. Study of new and novel designs will enrich this field of study and pave the road to reach optimal receiver. The objective of this study is to develop the existing design further towards the best design. Cavity receivers, especially conical receivers are known for high thermal efficiency. This study investigate four designs of conical receivers, three of them are novel designs using Ansys Fluent software. The investigated receivers are helical conical, pentagon conical, rectangular conical, and triangle conical respectively in the order of their performance. At 300 K the thermal performance of the best receiver which is helical conical is 66.68%, and the optical efficiency are 89.2%.

Power Generation using Thermoelectric Power Generator with Parabolic Solar Dish Concentrator

Solar Thermoelectric Generator (STEG), a hybridization system of thermoelectric generator (TEG) with a heat exchanger have been thoroughly explored because of its ability to produce both electricity and heat simultaneously. In this research, two tests were conducted: single TEG characterization test and STEG application. A theoretical modelling was developed based on the characterization test. For the STEG application, a solar parabolic dish concentrator and a single TEG were used to produce both heat and electricity simultaneously. An absorber plate placed on the focal point of the dish was used to facilitate the heat transfer of the reflected solar radiation to the TEG through the plate. The effects of various temperature difference were investigated. The absorber plate thickness was 1 mm and made up from copper to ensure high heat transfer rate and was well insulated so as to ensure minimal heat loss. To evaluate the performance of the TEG under the various temperatures, water-cooled cooling method (with water cooling jacket) and air-cooled cooling method (with finned heat sink and USB powered fan) were employed. Results showed that water-cooled cooling method was able to enhance the performance of STEG for higher power generation than air-cooled cooling method.