Parabolic Trough Collector

This paper demonstrates the construction designing analysis and control strategies for fully tracking concentrated solar thermal by using programmable logic control in the city of Erbil-Iraq. This work used the parabolic dish as a concentrated solar thermal. At the focal point, the collected form of energy is used for heating a (water) in the receiver, analyzing this prototype in real-time with two different shapes of the receiver and comparing the results. For tracking the parabolic dish, four light-dependent resistors are used to detect the sun's position in the sky so that the tracking system follows it to make the beam radiation perpendicular to the collector surface all of the time during the day for maximum solar power energy. This work discusses the essential stages of a two-axis prototype; implementation, solar-location strategy, the analysis in terms of theory, structural design, and material. For two-axis-prototype is implemented with the help of programmable logic control-Siemens (S7-1200) as a control unit. This study results show that a parabolic dish tracker with a cylindrical conical receiver obtains 15.25% Improved efficiency in comparison to the cylindrical receiver. According to the testing results of the prototype design, both shapes of the receiver are convenient for steam production.

Abstract- The urgent challenge of climate change calls for innovative energy solutions that reduce greenhouse gas emissions and strengthen system resilience. Solar thermal technology, when enhanced by advanced fluid dynamics, offers a promising pathway towards sustainable clean energy. This study simulates the performance of hybrid nanofluids, specifically copper and titanium dioxide nanoparticles dispersed in water, to improve heat transfer efficiency in parabolic solar thermal collectors. The governing nonlinear partial differential equations describing mass, momentum, energy, concentration, and magnetic induction are reduced to ordinary differential equations using similarity transformations and solved using MATLAB’s collocation based bvp4c solver. The model assumes two-dimensional laminar flow, thermal equilibrium between fluid phases, and temperature dependent hybrid nanofluid properties. Parametric analysis shows that Brownian diffusion and thermophoresis significantly influence velocity, temperature, and nanoparticle concentration, while Prandtl and thermal Grashof numbers strongly govern convective transport and MHD coupling. The findings provide deeper physical insight into hybrid nanofluid dynamics under electromagnetic influences and support the optimization of solar thermal collectors for enhanced thermal performance. The study contributes to Sustainable Development Goals 13 by advancing efficient and climate resilient clean energy technologies

In this study, the coldest days of 2022 in the Djelfa region, Algeria, were determined using astronomical and climatic data. The timing of sunrise, sunset, and duration of sunlight, as well as changes in solar radiation intensity and air temperature, were analyzed. By converting solar radiation into heat and solving differential equations, the study examined water exit temperature, thermal energy, and total yield as outputs of a renewable energy converter. The effect of different glass coverings on these outputs was also investigated. The coldest day in 2022 was found to be the first day of January, with nine hours and 43 minutes of sunlight, a maximum solar radiation intensity of 670.34 MW/m², and a maximum air temperature of 16.9 °C. The outputs of the solar center followed a parabolic pattern for the first two parameters and increased over time for the remaining outputs, regardless of the glass type. However, using glass with a high emission coefficient, such as clear monochromatic glass, resulted in the highest values for the outputs: 52.57 °C, 7.5 kW, 162 MW, and 70.62%. By understanding solar energy conversion and thermal behavior, the study contributes to energy-efficient designs and renewable integration, aiding in sustainable urban development. Findings can inform decision-makers in optimizing material selection, promoting resilient infrastructure, and advancing sustainable practices for a low-carbon future.

Parabolic trough collectors often face efficiency losses due to limited heat transfer and high pressure drops. This study numerically investigates the combined impact of ternary hybrid nanofluids and twisted tape inserts on thermal performance under turbulent flow (Reynolds number from 10,000 to 20,000). Using ANSYS Fluent, 15 models were developed with varying twisted tape configurations (0-4 inserts) and ternary hybrid nanofluid concentrations (0-24 wt%), assuming single-phase nanofluid flow under a 600 kW/m² non-uniform heat flux. Results show that the maximum Nusselt number improvement (44.3%) and friction factor enhancement (62.3%) occur in the model using 4 twisted tapes and 24 wt% ternary hybrid nanofluid. Also, the performance evaluation criterion reaches 1.219 using the optimal model with 2 twisted tapes and 24 wt% ternary hybrid nanofluids. These findings suggest that combining nanofluids and passive inserts can substantially enhance the thermal performance of parabolic trough collectors, guiding the design of next-generation solar receivers.

This paper presents the development and evaluation of a prototype refrigerated cooling table for conference services. The major components of the table are compressor, condenser, evaporator, capilary tube, thermostat and table metal wooden frame. The table uses vapour compression cycle based on the Evans-Perkins (reverse Rankine) cycle as its principle of operation. The evaporator has three cabinet ports. Plywood and square mild steel pipes are used for the construction of the table frame. The refrigerated cooling table successfully reduces temperature of beverages from 35°C to 15.5°C, 13°C and 11°C, when placed in a plastic, glass and stainless steel containers respectively. The refrigerated cooling table performs better when compared with a standard domestic refrigerator. The coefficient of performance using experimental values is 5.14 with a compressor power of 69.3W for three participants.

This  study  rigorously  evaluates  the  techno-economic  feasibility  of  parabolic-trough collector(PTC) for  thermal enhanced oil recovery  (EOR)  by  benchmarking  it  against  conventional  diesel-fired  boiler  steam  supply  across  geographically  diverse  thermal-EOR  fields.  Site-specific  direct normal irradiancedata from NREL’s NSRDB are used to characterize the solar resource and size the  collector  aperture  area.  Techno-economic  calculations  and  scenario  evaluation  are  conducted using HOMER Pro, while the proposed PTCconfiguration includes thermal energy storagewith an equivalent  duration  of  6  h/day  and  is  assessed  under  a  representative  capacity  factor  of  0.6, reflecting partial coverage of steam-load demand. A harmonized levelized cost of energy (LCOE) framework  is  applied  to  both  configurations  under  consistent  financial  assumptions  to  enable  an apples-to-apples  comparison.  Results  show  that  boiler-based  LCOE  is  strongly  driven  by  local diesel  pricing  and  heat-duty  requirementsthe  Netherlands  (NLD)  exhibits  the  highest  boiler LCOE,  whereas  Venezuela  (VEN1)  yields  the  lowest.  A  second  Venezuelan  case  (VEN2) produces  an  anomalously  high  boiler  LCOEaround4.5,  attributable  to  an  exceptionally  large reported heat  duty;  it  is  therefore  treated  as  an  outlier  with  elevated  uncertainty.  PTCinvestment inputs  are  parameterized  using  NREL  benchmark  unit  costs  24.375  SAR/kW  installation,  712.5 SAR/m2solar  field,  and  93.75  SAR/kWh  thermal  storage.  Beyond  cost  competitiveness,  solar steam  substitution  provides  a  credible  pathway  for  fuel  displacement  and  associated  CO2mitigation;  reported  solar-EOR  deployments indicate  annual  CO2reductions  ranging  from 104  to 636,720 tCO2/year, depending on plant scale.

Concentrating solar power (CSP) systems use solar absorbers to convert sunlight into thermal electric power. In CSP systems, a high reflective surface focuses sunlight onto a receiver that captures the solar energy and converts it into heat. The operation of high efficiency CSP systems involves improvements in the performance of the coatings of the solar absorption materials. To accomplish this, novel, more efficient selective coatings are being developed with high solar absorptance and low thermal losses at their operation temperature. Heat losses in a CSP system occur by three mechanisms: conduction, convection and radiation. It has been widely documented that energy losses increase with increasing operating temperature of CSP systems, and the precise knowledge of the thermophysical properties of the materials involved in CSP systems may allow us to increase the efficiency of systems. In this work, we applied the pulsed photoradiometry technique (PPTR) to evaluate the changes in t...

Design, construction and characterization of an evacuated 1.3 m long, tubular solar collector are presented. The collector is open at both ends for input and output of the fluid to be heated, and at one end a commercial, stainless steel bellows is soldered at the metal-glass seal, which allows for the higher thermal expansion coefficient of the steel tube as compared to the glass jacket. A selective coating of Ni/NiOwas electrochemically deposited on the stainless steel tubecollector using a two-step process. Collector losses are characterized up to 200 o C as a function of pressure in the space between the borosilicate glass and the stainless steel tube. A16-channel thermocouple system was used to characterize the dynamic thermal behavior of the collector. The suppression of convection as a heat transport mechanism in the vacuum zone is demonstrated for a pressure of 10 -4 Torr. The absorption characteristics of the collector were studied by placing it outside on a sunny day. A cri...