Parabolic Collector Research Articles

Assessment of Conical Solar Stills Empowered by N-Replicated Partially Shaded PVT-CPC Collectors: Unveiling Exergo-Enviro-Economic Dynamics, Productivity, and Cogeneration Efficiency

Abstract The economic and environmental dimensions play a pivotal role in evaluating solar still systems. The aim of this study is to evaluate the performance, efficiency, and viability of conical solar still integrated with multiple identical photovoltaic thermal compound parabolic collector (PVT-CPC) through comprehensive analyses of cogeneration efficiency, exergo-economic and enviro-economic factors, and productivity metrics. The results of this study were obtained through matlab programming, enabling accurate and detailed computations. The model has been validated at N = 0 and N = 1, showing strong correlation results: 0.96 and 0.97 for water temperature, 0.99 for yield in both cases, and 0.99 and 0.98 for glass temperature. The system has achieved a total carbon emissions mitigation of 108.29 tCO2 based on energy and 12.44 tCO2 based on exergy while recording an annual yield of 2199.61 kg. The annual cogeneration efficiency, exergo-economic parameter, enviro-economic parameter, and annual productivity are 38.96%, 31.98 kWh/$, $1570.20, and 244.68%, respectively. Furthermore, the obtained results have been compared with prior research and concluded that the exergo-economic and enviro-economic parameters for the proposed system are increased by 93.54% than the solar still with water-cooled condensing surface and 94.71% than solar still containing partially coated condensing cover with thermoelectric cooling.

Optimization of condensing tray shapes for a multi‐effect solar still coupled with parabolic solar collectors for domestic wastewater treatment: A comparative study

AbstractThe issue of water depletion emerged as a life‐threatening problem for the world due to urbanization, groundwater over‐extraction, industrialization, and global warming. Current study aimed to address this issue by proposing a solution to distill wastewater using a multi‐effect solar still. The study optimizes two condensation tray shapes, U and V, based on the yield produced and the temperatures achieved. Two solar still units with four stages of U and V‐shaped trays were connected to a parabolic solar collector. To determine the optimal tray shapes, a rigorous optimization process was carried out using SolidWorks 2020. The optimization process yielded optimum heat flux values of 3.04e01 and 2.84e01 W/m2 for U and V‐shaped trays, respectively. Higher the value of heat flux suggested more energy available for condensation. Which was corroborated by physical findings that the U‐shaped condensation tray was more efficient, producing an average per day yield of 2.519 L/m2 h compared to the V‐shaped tray's yield of 2.041 L/m2 h. The findings provide strong evidence that the U‐shape is a better tray shape for condensation purposes. Maximum yield for both units was observed during the peak temperature time between (13:00–15:00 h), indicating a direct correlation between yield and atmospheric temperature.

Comparative Techno-Economic Analysis of Parabolic Trough and Linear Fresnel Collectors with Evacuated and Non-Evacuated Receiver Tubes in Different Geographical Regions

In the context of Concentrated Solar Power (CSP) technology, this paper presents a comparison between the Parabolic Trough Collector (PTC) and the Linear Fresnel Collector (LFC), considering both evacuated and non-evacuated receiver tubes. The comparison was carried out in terms of the Levelized Cost of Electricity (LCOE) considering a reference year and four locations in the world, characterized by different levels of direct normal irradiation (DNI) from 2183 kWh/m2/year to 3409 kWh/m2/year. The LCOE depends on economic parameters and on the net energy generated by a plant on an annual basis. The latter was determined by a steady-state 1D model that solved the energy balance along the receiver axis. This model required computing the incident solar power and heat losses. While the solar power was calculated by an optical ray-tracing model, heat losses were computed by a lumped-parameter model developed along the radial direction of the tube. Since the LFC adopted a secondary concentrator, no conventional correlation was applicable for the convective heat transfer from the glass cover to the environment. Therefore, a 2D steady-state CFD model was also developed to investigate this phenomenon. The results showed that the PTC could generate a higher net annual energy compared to the LFC due to a better optical performance ensured by the parabolic solar collector. Nevertheless, the difference between the PTC and the LFC was lower in the non-evacuated tubes because of lower heat losses from the LFC receiver tube. The economic analysis revealed that the PTC with the evacuated tube also achieved the lowest LCOE, since the higher cost with respect to both the LFC system and the non-evacuated PTC was compensated by the higher net energy yield. However, the non-evacuated LFC demonstrated a slightly lower LCOE compared to the non-evacuated PTC since the lower capital cost of the non-evacuated LFC outweighed its lower net annual energy yield. Finally, a sensitivity analysis was conducted to assess the impact on the LCOE of the annual optical efficiency and of the economic parameters. This study introduces key technical parameters in LFC technology requiring improvement to achieve the level of productivity of the PTC from a techno-economic viewpoint, and consequently, to fill the gap between the two technologies.

A review on phase change material's applications in solar parabolic dish collectors

A review on phase change material's applications in solar parabolic dish collectors

Performance Optimization of Pulsating Heat Pipe Integrated Compound Parabolic Solar Collector Using Hybrid Red Fox Optimizer based DNN (DNN-RdFx)

Performance Optimization of Pulsating Heat Pipe Integrated Compound Parabolic Solar Collector Using Hybrid Red Fox Optimizer based DNN (DNN-RdFx)

Solar Organic Rankine Cycle (ORC) Systems: A Review of Technologies, Parameters, and Applications

The Organic Rankine Cycle (ORC) is a widely utilized technology for generating electricity from various sources, including geothermal energy, waste heat, biomass, and solar energy. Harnessing solar radiation to drive ORC is a promising renewable energy technology due to the high compatibility of solar collector operating temperatures with the thermal requirements of the cycle. The aim of this review article is to present and discuss the principles of solar-ORC technology and the broad range of solar-ORC systems that have been explored in the literature. Various solar energy technologies capable of powering ORC are investigated, including flat plate collectors, vacuum tube collectors, compound parabolic collectors, and parabolic trough collectors. The review places significant emphasis on the operating parameters of technology.

Ultra-low temperature heating system based on dual-source solar assisted heat pump using compound parabolic concentrator-capillary tube solar collector

The fifth-generation heating – ultra-low temperature heating benefits to reduce electricity consumption and achieve the net zero goal. The dual-source solar assisted heat pump based heating system has been demonstrated to be an attractive green heating technology for the domestic sector. However, the slower response speed of the low temperature heating to the variation of heating load in responding to the variations of weather conditions limits its thermal comfort performance. The enhancement in solar collector performance brings valuable improvements in response speed of the heating system. In the present work, a heating system based on solar assisted air source heat pump using a compound parabolic concentrator-capillary tube solar collector (CPC-CSC) is investigated with the set heating temperatures of 40, 45, 50, and 55 °C. This heating system works for both space heating and hot water under the weather conditions in London. The results suggest that using a concentrated solar collector improves the response speed of the heating system at low set heating temperatures. For such a heating system, the ultra-low heating temperature increases the application of renewable energy and passive heating (by 6.4%). Compared with the dual-source indirect expansion solar assisted heat pump using flat plate collector, the heating system using CPC-CSC can reduce TEWI by 4.6% with a slightly longer (1.9%) payback period. As the set heating temperature decreases from 55 to 40 °C, the seasonal and yearly system seasonal performance factors significantly increase by 17.1% and 20.5%, respectively.

Energy and Exergy Performance Analysis of Solar-Assisted Thermo-Mechanical Vapor Compression Cooling System

Air conditioning is vital for indoor comfort but traditionally relies on vapor compression systems, which raise electricity demand and carbon emissions. This study presents a novel thermo-mechanical vapor compression system that integrates an ejector with a conventional vapor compression cycle, incorporating a thermally driven second-stage compressor powered by solar energy. The goal is to reduce electricity consumption and enhance sustainability by leveraging renewable energy. A MATLAB® model was developed to analyze the energy and exergy performance using R1234yf refrigerant under steady-state conditions. This study compares four solar collectors—evacuated flat plate (EFPC), evacuated tube (ETC), basic flat plate (FPC), and compound parabolic (CPC) collectors—to identify the optimal configuration based on the collector area and costs. The results show a 31% reduction in mechanical compressor energy use and up to a 44% improvement in the coefficient of performance (COP) compared to conventional systems, with a condenser temperature of 65 °C, a thermal compression ratio of 0.8, and a heat source temperature of 150 °C. The evacuated flat plate collectors performed best, requiring 2 m2/kW of cooling capacity with a maximum exergy efficiency of 15% at 170 °C, while compound parabolic collectors offered the lowest initial costs. Overall, the proposed system shows significant potential for reducing energy costs and carbon emissions, particularly in hot climates.

Sustainable innovation for fermented cassava roasting: Examining the potential of parabolic dish solar collectors and thermal energy storage

Fermented cassava roasting is an energy-intensive process that is commonly used to produce gari, a popular food in Nigeria made from cassava. Traditional roasting methods use firewood as an energy source, which is inefficient and harmful to the health of those who inhale the smoke (mainly women and children in rural communities) and contributes to deforestation. This work aims to investigate a developed fermented cassava roasting system driven by a concentrated parabolic solar collector. Important data on the gari production food chain was obtained from a work-study in a rural community: temperatures and moisture content. The roasting temperatures range between 85oC - 100oC. The parabolic dish solar collector was designed and fabricated to achieve temperatures between 118oC-154oC at optimum tilt angles at Port Harcourt (4°54′ 22.86″N, 6°55′ 27.52″E) climatic conditions. The focal length ranges between 50 mm and 80 mm, and the fluctuation of the focal point position was considered for the thermal storage system design. Gravel was used as a thermal storage, and heat transfer was enhanced through small internally placed mild steel rods. The experimentally obtained average total fry/roast time per batch (40g) was 24 min, which is greater than the theoretically obtained value of 8.5 min. The fermented cassava roasting experiment was conducted for three days with favourable weather conditions, achieving a maximum temperature of 101oC. This innovation is important in addressing the health risks associated with traditional fermented cassava roasting methods and moving towards zero-emission and zero-poverty innovative systems.

Investigating the performance of an affordable parabolic dish collector with double glass vacuum cavity cover

Parabolic dish collectors (PDC) are one of the most important ways to concentrate solar energy. In this study, the performance of a low-cost parabolic dish collector with high average output temperatures is investigated. The low-cost PDC has a 45 ° edge angle and a circular receiver. A vacuum double-glazed cavity is used to keep heat inside the receiver and reduce the rate of heat losses. On clear and cloudy days, tests were conducted with thermal oil as a heat transfer fluid (HTF) to analyze the performance of the PDC. The results show that the change in temperature of the heat transfer fluid between the open and closed ends of the cavity receivers affected the receiver heat gain, thermal efficiency, and exergy efficiency. It was also found that the HTF has the highest exit temperature of 221 °C, with an average radiation intensity of 1032 W/m2. With 48.4 % thermal efficiency and 9.1 % exergy efficiency, the results showed the best performance. When it came to total efficiency, PDC showed its highest value of 46.2 % at 13:17 p.m. on January 4th, 2024.

Silicon porous disc featured parabolic trough collector functioned with paraffin: Thermal performance study

The advancement of renewable solar energy has potential for industrial heat exchanger applications, and its performance is enhanced by using nanofluid. Besides, the losses of heat during the energy transfer from solar to heat exchanger limit thermal performance and lead to reduced thermal efficiency. The conventional solar system functioning with nanofluid needs to be upgraded with an advanced thermal management system to limit energy loss and enrich the thermal performance of the overall system. The investigation aims to enrich the thermal performance of a parabolic trough solar collector (PTC), which features silicon porous discs and phase change material (PCM-paraffin). During the investigation, the flow of fluid ranged from 100 to 200 LPH with an interval of 50 LPH. Influences of silicon porous disc and phase change material melting phase on fluid temperature, temperature, energy stored, and thermal efficiency of the present system are experimentally investigated, and its values are related to conventional absorber performance without porous material and phase change material. The output results prove the significance of silicon porous and phase change material related to conventional absorber systems. The parabolic solar collector functioned with silicon porous material with phase change material phase on 200LPH spotted superior thermal performance including fluid temperature, PCM temperature, energy stored by phase change material, and average thermal & exergy efficiency of 84.2 °C, 98.5 °C 599.7 kJ, and 73.8 % & 15.1 %. These findings underscore the promising potential of porous medium absorbers in significantly elevating the efficiency of parabolic trough collector systems.

Scaling-up the use of macroscopic photo-CWPO La1-xTixFeO3/SiC alveolar foam catalyst for solar water treatment against micropollutants

Current wastewater treatment plants are not prepared for the removal of micropollutants like phenol, pharmaceuticals and pesticides in water. As their release into the environment has adverse consequences towards the living organisms of ecosystems, the engineering of novel sustainable processes able to ultimately remove the emerging organic contaminants is an objective of paramount importance. Hereby we report for the first time on the successful scale-up of a macroscopic photo-CWPO La1-xTixFeO3/SiC alveolar foam catalyst used at the pilot-plant scale inside a Compound Parabolic Collectors based photoreactor. The removal of a span of organic micropollutants in water matrices of different complexity was efficiently realized under natural solar radiation using H2O2 or persulfates as oxidizing agent. The water matrix composition affected the efficiency of the degradation process. Using H2O2, for a collected energy of ca. 27 KJ/mol, the rate of micropollutant removal ranged from 53 % to 95 % in distilled water depending on the micropollutant in a cocktail configuration. It was lowered to the 17–66 % range in tap water, and to the 8–42 % range in simulated urban wastewater. The results demonstrated the promise of using sodium persulfate as oxidant instead of H2O2, with a better efficiency towards the removal of most of the micropollutants tested. The use of the sodium persulfate oxidant allows for overcoming the drawbacks associated to the treatment of real water matrices observed using H2O2, as better performances were reached when increasing the water matrix complexity. Complete removal of carbamazepine and diclofenac micropollutants was reached in tap water and simulated urban wastewater for ca. 27 KJ/mol of collected energy. The degradation performances combined to the catalyst robustness make this water treatment technology promising for operating in a continuous way under natural solar light.

Performance Analysis of a Renewable‐Powered Multi‐Gas Floating Storage and Regasification Facility for Ammonia Vessels With Reconversion to Hydrogen

ABSTRACTNatural gas and renewable energy carriers play critical roles in the energy supply chain due to rising energy consumption demands and a significant shift toward cleaner energy. However, the requirement to liquefy and regasify liquefied natural gas (LNG) and renewable energy carriers for transportation makes the entire process expensive and challenging. Hence, a floating storage and regasification unit (FSRU) plant provides a solution to the aforementioned problems with the additional benefit of being more affordable, time‐efficient, and having less land footprint requirement than the conventional onshore facility. The proposed integrated FSRU in this study, is powered by renewable energy, including solar and ocean thermal energy. The subsystems of integrated FSRU consist of parabolic dish collectors (PDC), Rankine cycle, organic Rankine cycle (ORC), multi‐stage flashing (MSF) desalination unit, decomposition, reliquefication, and regasification plants, which provide valuable commodities such as freshwater, electricity, hydrogen, and heating. It can also cater to standard multi‐gas harboring vessels for storage and regasification of sustainable energy carriers. The study assesses the performance of the proposed system thermodynamically by analyzing mass, energy, entropy, and exergy balance equations using the engineering equation solver (EES) software. Furthermore, parametric studies were conducted to understand the interlinkage among various variables. The analytical results show that the proposed system is able to produce 1.82 MW of electricity, 2056 kg/day of fresh water, and 338.3 kg/day of hydrogen, achieving an overall system energy efficiency of 32.7% and exergy efficiency of 79.3%. This approach aims to foster energy diversification, enhance energy security, and support the transition toward sustainable energy systems, as well as further the advancement of maritime transport systems.

Field measurements reveal insights into the impact of turbulent wind on loads experienced by parabolic trough solar collectors

To ensure efficient and reliable operation of a concentrating solar-thermal power (CSP) plant, its solar collector field needs to accurately focus sunlight. The optical efficiency and structural integrity of the solar collectors is significantly influenced by wind conditions in the field. In this study, we present insights into dynamic wind loading on parabolic trough CSP collectors. We derive novel conclusions by analyzing a first-of-a-kind measurement campaign of wind and structural loads, performed at an operational CSP plant. Previous research primarily relied on wind tunnel tests and simulations, leaving uncertainty about wind loading effects in operational settings. We demonstrate that the parabolic trough field significantly alters the turbulent wind field within the collector field, especially under winds perpendicular to the trough rows. Our measurements within the trough field show reduced wind speeds, changes in wind direction and turbulence properties, and vortex shedding from the trough assemblies. These modifications to the wind field directly impact both static and dynamic support structure loads. Our measurements reveal higher wind loads on trough assemblies compared to those observed previously in wind tunnel tests. The insights from this study offer a novel perspective on our understanding of wind-driven loads on CSP collectors. By informing the development of next-generation design tools and models, this research paves the way for enhanced structural integrity and improved optical performance in future parabolic trough systems.

Analysis of the thermodynamic performance of the SOFC-GT system integrated solar energy based on reverse Brayton cycle

Efficient power generation systems are an essential way to reduce carbon emissions. To avoid the complex effects of high-pressure conditions on the solid oxide fuel cell (SOFC) and gas turbine (GT) hybrid systems, while further improving energy efficiency. A SOFC-GT hybrid system based on the reverse Brayton cycle (RBC) is proposed, in which the SOFC operates at near atmospheric pressure conditions and GT expands below atmospheric pressure. Solar energy is integrated to further enhance system performance. Rigorous assessments of the novel system and the pressurized system are conducted utilizing energy, exergy and economic analysis. The sensitivity analysis of environmental parameters on the novel system's performance is performed. The results show that the novel system generates power and efficiency better than the conventional system when the GT compression ratio is 3 and 6, respectively. The power generation and exergy efficiency of the novel system at the design point is 60.47 % and 58.57 %, respectively. The largest exergy destruction occurred in the SOFC. The lowest exergy efficient components are the parabolic dish collector (PDC) and heat exchanger 2. The novel system is more cost-effective due to the higher lifetime of the SOFC, with the levelized cost of energy (LCOE) is 0.1418 $/kWh.

Comparative review and novel design possibilities on solar-driven absorption LiBr-H2O refrigeration system

Solar energy is a promising source of energy because of its potential due to the reduction usage of non-renewable energy. As the demand for cooling increases, solar-powered cooling technologies are becoming increasingly promising. Among the different solar cooling systems, LiBr-H2O absorption chillers are commonly used due to their advantages over NH3-H2O systems. Multiple cycle LiBr-H2O chillers can be powered by easily available flat-plate, evacuated tubular or parabolic solar collectors. This paper reviews Theoretical Principles-Based Analysis and Simulations of solar LiBr-H2O absorption cooling systems, performance comparison of each types and introduces new design options related to auxiliary energy systems and cooling mode cycle. The paper also summarizes other main types of solar absorption cooling systems, including double-effect, half-effect, triple effect and give updates of new technology design of hybrid effect. The choice of water-cooled or air-cooled absorption refrigeration depends on the local climate and water availability. Recent advances have made air-cooled absorption refrigeration a viable option, with comparable COP to water-cooled systems and lower maintenance requirements. Additionally, geothermal heat rejection with low pressure drops can further reduce energy consumption. Solar-powered double-effect absorption cooling systems are recommended for buildings with high cooling loads, while half-effect are suitable for air-cooled solar absorption cooling systems in hot and dry regions with limited water. This paper is specifically intended for those interested in developing solar-driven LiBr-H2O absorption chillers, emphasizing the importance of establishing standardized design guidelines to specific regions and climates in order to promote and expand the usage of solar cooling systems.

Thermal Analysis of Parabolic and Fresnel Linear Solar Collectors Using Compressed Gases as Heat Transfer Fluid in CSP Plants

This study introduces the use of compressed air as a heat transfer fluid in small-scale, concentrated linear solar collector technology, evaluating its possible advantages over traditional fluids. This work assumes the adoption of readily available components for both linear parabolic trough and Fresnel collectors and the coupling of the solar field with Brayton cycles for power generation. The aim is to provide a theoretical analysis of the applicability of this novel solar plant configuration for small-scale electricity generation. Firstly, a lumped thermal model was developed in a MatLab® (v. 2023a) environment to assess the thermal performance of a PT collector with an evacuated receiver tube. This model was then modified to describe the performance of a Fresnel collector. The resulting optical–thermal model was validated through literature data and appears to provide realistic estimates of temperature distribution along the entire collector length, including both the receiver tube surface and the Fresnel collector’s secondary concentrator. The analysis shows a high thermal efficiency for both Fresnel and parabolic collectors, with average values above 0.9 (in different wind conditions). Th5s study also shows that the glass covering of the Fresnel evacuated receiver, under the conditions considered (solar field outlet temperature: 550 °C), reaches significant temperatures (above 300 °C). Furthermore, due to the presence of the secondary reflector, the temperature difference between the upper and the lower part of the glass envelope can be very high, well above 100 °C in the final part of the collector string. Differently, in the case of PTs, this temperature difference is quite limited (below 30 °C).

Experimental investigations for enhancing the performance of hemispherical cavity receivers using additively manufactured heat exchangers

ABSTRACT This research explores a pioneering approach in cavity-type solar parabolic dish collector technology (SPDCT) by introducing a novel, additive-manufactured thermally conductive polymer composite heat exchanger over a modified hemispherical cavity receiver for heat recovery applications. This manuscript investigates the performance of innovative configuration of SPDC for Wardha (442001), Maharashtra State (027), INDIA, 20.75° N, 78.65° E, modifying the traditional setup by employing copper coil with different arrangements. The unique aspect of this research lies in the implementation of a hemispherical cavity receiver with preheating water arrangement by installing a thermally conductive polymer composite (TCPC) heat exchanger developed with compositions TPU/MWCNT/GNP of 93/3.5/3.5 by wt.% using an additive manufacturing technique, a strategy not previously explored in the existing literature. A computational study (steady state thermal analysis) conducted using ANSYS Student Version R2023 revealed substantial heat availability over the receiver’s top exterior, forming the basis for the experimental tests. Under different test conditions, the highest thermal efficiency improvement reached to 10.91%. This paper contributes novel ideas to the field, emphasizing the potential of additive-manufactured thermally conductive polymer heat exchangers to increase the performance of solar parabolic dish collector systems.

Energy-efficient production of sustainable industrial process heat with a parabolic dish-conical cavity solar collector

Industrial decarbonization in response to global carbon neutrality requires vast process heat to be supplied in a low-carbon manner. Solar energy is regarded as one of the most promising alternatives to fossil fuel applied for heat-driven industrial processes, however, lack of effective approaches to improve the solar-thermal conversion efficiency is a longstanding issue. Here, we propose an efficient approach to produce industrial process heat based on a novel concentrated solar collector, mainly consisting of a parabolic dish concentrator and a conical cavity receiver. Results showed that the collector was competent to supply the process heat meeting various low-temperature industrial occasions, and there was an optimum flow rate to achieve a trade-off between the outlet temperature of working fluid and thermal efficiency of the solar collector. The thermal efficiency of the proposed solar collector was 2.7%–27.5% higher than that of most other existing collectors used for production of low-temperature process heat, and such a superior solar-thermal conversion efficiency was a consequence of the reduction in energy losses between the solar receiver and surroundings as confirmed by the comprehensive energy analysis performed in this study.

Experimental investigation of an off-grid CPC system integrated with a radiator for the application of space heating

Compound parabolic collectors (CPC) are non-tracking concentrators capable of producing lower to medium-range heating (temperature range of 50–80 °C), making them suitable for space heating applications. CPCs raise the heat transfer fluid temperature to a specific value depending upon the solar irradiation received at the location. In this study, CPC is used to harness the solar energy, and an insulated tank is used to store thermal energy. To facilitate space heating, the hot fluid from the thermal storage tank is passed through a radiator, transferring the thermal energy from the tank to the target heating load. The overall setup consists of two loops with water as heat transfer fluid. Both loops consist of a pump that uses solar PV power. An experimental test setup was installed to measure the ambient heat transfer fluid, radiator fin, and room temperature. The combined system was tested for its performance under actual weather conditions prevailing in the area. Experiments were performed to investigate space heating potential at night, evening, and full day. The energy stored and collector efficiency were calculated for each day. The total thermal energy stored in the tank on a typical day was 67.79 MJ, and the collector efficiency was evaluated to be around 43.7 %. As per the experiment results, the combined CPC and radiator system have a significant potential to be explored in space heating.