Parabolic Trough Collector Receiver Research Articles

The Effect of Uneven Metal Foam Distribution on Solar Compound Parabolic Trough Collector Receiver Thermal Performance

Solar energy is a key player among other renewable energies that reduce greenhouse gases and replace conventional fuel, i.e., to solve global warming and fossil fuel descending issues. However, the thermal solar systems’ performance should be enhanced to cope with intermittent solar radiation. Metal foam can be used as an enhancer in solar collectors’ receivers. However, metal foams are associated with pressure drop. To benefit from the metal foam as a thermal enhancer and overcome the pressure drop issue, the present study numerically and experimentally investigates a novel Compound Parabolic Solar Collector (CPC) receiver with innovative uneven metal foam inserts of varying thickness. Two pores per inch (PPI) Cu-foam inserts, PPI10 and PPI20, were tested. These inserts were strategically placed at three different positions along the receiver, with thicknesses of 3 cm, 2 cm, and 1 cm starting from the inlet side. In the experimental part, three tubular receivers were tested, empty, i.e., without metal foam, inserted with Cu-foam of PPI10, and inserted with Cu-foam of PPI20. The experiments were conducted from 09:00 AM to 04:00 PM. The investigation involved water volume flow rates from 0.2 to 0.6 l/min. The numerical part included solving the governing equations, i.e., mass, momentum, and energy conservation, simulating conditions similar to the experiments. The Brinckman model described the fluid flow through the metal foam. The thermal performance of the CPC system was evaluated using the Nusselt number (Nu), thermal efficiency, water bulk temperature, and water outlet-inlet temperature difference. Inserting Cu-foam of PPI20 resulted in the hourly maximum Nu and thermal efficiency compared to the empty and PPI10 cases. Experimentally, the hourly maximum Nu was 8.9, 8.4, and 7.9 for PPI20, PPI10, and empty receivers, respectively, at 0.6 l/min. The average thermal efficiency was 88.3, 85, and 81.9 for PPI20, PPI10, and empty receivers, respectively, at 0.6 l/min. As for the outlet-inlet water temperature difference, the highest values were at 0.2 l/min. Again, PPI20 recorded the best results, i.e., 23.3 K, 21.5 K, and 20.2 K for PPI20, PPI10, and empty cases, respectively.

Investigation of parabolic trough collector receiver with U-pipe exchanger using a numerical approach: Towards temperature non-uniformity optimization

In this work, a numerical study of the heat flux and temperature distribution for a parabolic trough collector absorber with an internal U-pipe tube exchanger is carried out using SolTrace and ANSYS Fluent software. The effect of solar flux and temperature non-uniformity on the system performance related to the focal distance is investigated. It was noticed that the highest circumferential temperature gap of about 105 °C occurs at the medium of the absorber (0.9 m). Moreover, for the focal distances of 0.18 m, 0.19 m, and 0.2 m, the outlet water temperatures are increased to 328.8, 329.01 and 328.89 K, respectively. For these distances, the highest thermal efficiencies of about 69, 70 and 71%, respectively, are reported. Furthermore, the promising proposed approach to investigate the receiver performance combines simulation results and correlations between variables. Indeed, a strong negative correlation of −0.65 between thermal efficiency and focal distance is noticed. Thus, thermal efficiency correlates positively with maximum temperature gap, inlet–outlet temperature gap, flow rate, and outlet temperature in decreasing order with correlation coefficients of 0.64, 0.59, 0.38, and 0.32, respectively. Additionally, the simulation study emphasizes the importance of relating optimum temperature uniformity and thermal efficiency for optimizing the system performance.

Exergetic, Energetic, and entropy production evaluations of parabolic trough collector retrofitted with elliptical dimpled receiver tube filled with hybrid nanofluid

In this paper, a numerical study was performed on a parabolic trough collector receiver tube containing elliptical dimpled fins with different elliptical ratios (ER = 0.66–1.66) under turbulent flow regime. The C++ code was developed to perform a non-uniform heat flux on outside of the receiver tube to get approximation real working conditions. Different mono and hybrid nanofluids and their combinations with different nanoparticle volume fractions (2.0 %TiO2/Syltherm800, 2.0 %Al2O3/Syltherm800, 0.5 %TiO2-1.5 %Al2O3/Syltherm800, 1.0 %TiO2-1.0 %Al2O3/Syltherm800, and 1.5 %TiO2-0.5 %Al2O3/Syltherm800) were used as a working fluid. The study provides a detailed analysis of the hydro-thermal characteristics, exergetic, and entropy production of the parabolic trough collector. 1.5 %Al2O3-0.5 %TiO2/Syltherm800 hybrid nanofluid shows the best increase in results obtained in this study using elliptical ratio of a/b = 5/3. The use of the elliptical ratio of a/b = 5/3, the average Nusselt number increases with 38 % compared to the receiver tube without elliptical dimpled fin. Total entropy generation was reduced up to 16.82 % for the elliptical ratio of a/b = 5/3. With the inserting elliptical dimpled fins of a/b = 5/3, the Performance Evaluation Criterion was detected as 1.81 compared to while the thermal efficiency increases from 74 % to 80 % at the lowest Reynolds numbers.

Heat Transfer Enhancement in a Receiver Tube of Solar Collector Using Various Materials and Nanofluids

The solar flux distribution on the Parabolic Trough Collector (PTC) absorber tube is extremely non-uniform, which causes non-uniform temperature distribution outside the absorber tube. Therefore, it generates high thermal stress which causes creep and fatigue damage. This presents a challenge to the efficiency and reliability of parabolic trough receivers. To override this problem, we have to homogenize the heat flux distribution and enhance the heat transfer in the receiver’s absorber tube to improve the performance of the PTC. In this work, 3D thermal and thermal stress analyses of PTC receiver performance were investigated with a combination of Monte Carlo Ray-Trace (MCRT), Computational Fluid Dynamics (CFD) analysis, and thermal stress analysis using the static structural module of ANSYS. At first, we studied the effect of the receiver tube material (aluminium, copper, and stainless steel) on heat transfer. The temperature gradients and the thermal stresses were compared. Second, we studied the effect of the addition of nanoparticles on the working Heat Transfer Fluid (HTF), employing an Al2O3-H2O based nanofluid at various volume concentrations. To improve the thermal performance of the PTC, a nanoparticle volume concentration ratio of 1%–6% is required. The results show that the temperature gradients and thermal stresses of stainless steel are significantly higher than those of aluminium and copper. From the standpoint of thermal stress, copper is recommended as the tube receiver material. Using Al2O3 in water as an HTF increases the average output temperature by 2%, 6%, and 10% under volume concentrations of 0%, 2%, and 6% respectively. The study concluded that the thermal efficiency increases from 3% to 14% for nanoparticle volume fractions ranging from 2% to 6%.

Numerical investigation of entropy generation in a solar parabolic trough collector using supercritical carbon dioxide as heat transfer fluid

• A Three-dimensional numerical thermal model is developed for solar Parabolic trough collector with s-CO2 as a heat transfer fluid. • Non-uniform solar heat flux calculated using Monte Carlos Ray Tracing based Optical Tool. • Entropy generation is calculated using the local temperature and velocity fields. • Optimal inlet boundary conditions were obtained for the s-CO2 as heat transfer fluid in the solar parabolic trough collector. Parabolic trough collector (PTC) is a widely used and efficient Concentrating Solar Power (CSP) technology for generating solar thermal power. Supercritical CO 2 (s-CO 2 ) is a heat transfer fluid (HTF) that shows good promising for use in solar PTC for further improvement in its efficiency and operations. A numerical thermal model is developed to understand the performance of s-CO 2 as an HTF in a solar PTC. The local temperature and velocity fields were used to calculate the entropy generated within HTF due to finite temperature differences and fluid flow friction. A commercially available LS-3 parabolic trough collector is used for the analysis with a modified receiver. An optical analysis tool based on Monte Carlo Ray tracing is used to calculate non-uniform heat flux distribution around the circumference of the PTC receiver. Entropy generated at various operating pressures, inlet temperatures, and inlet Reynolds number using s-CO 2 as HTF is calculated and analyzed. Results showed that entropy generated in the PTC receiver is reduced to a minimum at optimal Reynolds number for each of the operating pressures and inlet temperatures of the HTF. The Bejan number estimates the contribution of entropy generated due to heat transfer irreversibilities to the entropy generated due to heat transfer and fluid flow irreversibilities which is between 0.2 and 0.4 at high flow rates and close to 1 at low flow rates. Exergy efficiency analysis supported the optimized inlet boundary conditions.

Performance evaluation of solar parabolic trough receiver using multiple twisted tapes with circular perforation and delta winglet

A parabolic trough collector (PTC) is one of the concentrating types of a solar collector working in the medium range of temperature from 100–400 °C, for this reason, the efficiency of the solar parabolic trough is less than other types of concentrating solar collector (Point focusing types) in terms of solar to thermal energy conversion, the improvement in efficiency is achieved by various passive heat augmentation techniques in the receiver tube. One of the promising passive techniques is twisted tape inserts used in the receiver due to its simplicity in design and the various possibility of geometric modification. This paper deals with the performance evaluation of the solar parabolic trough receiver system by using passive techniques in the receiver. The testing of the receiver of PTC was done by using multiple perforated twisted tapes with winglets having different perforation ratios ([Formula: see text]) of 0.05, 0.15, 0.25, twist ratios ([Formula: see text]) of 3, 4, 5 and wing depth ratios ([Formula: see text]) of 0.1, 0.2 and 0.3. The number of twisted tapes was fixed at 4. The examination was conducted for Reynolds numbers ([Formula: see text]) varying from 3000–21,000 using air as working fluid. The outcome shows that the use of perforation and winglet in twisted tapes augment the Nusselt number as compared to that of smooth twisted tapes. The maximum thermohydraulic performance ([Formula: see text]) of 2.40 is received by using multiple twisted tapes with perforation and winglet having [Formula: see text] = 0.3, [Formula: see text] = 3, and [Formula: see text] = 0.05 at the Re = 21,000. The correlations for Nusselt number ([Formula: see text]) and friction factor ([Formula: see text]) are also developed with ± 8.5% and ± 8.3% accuracy, respectively.

Experimental analysis of heat loss of a non – evacuated parabolic trough collector receiver subjected to uniform and non-uniform wall heat flux condition

ABSTRACT The parameters that largely influence the design and performance of a parabolic trough collector system for delivering process heat are optical efficiency, incidence angle modifier, solar irradiation data, and receiver heat loss. The heat loss and optical properties of a receiver greatly influence the overall efficiency of the solar thermal system. This paper focuses the attention on the experimental investigation of heat loss associated with a non-evacuated receiver subjected to i). Uniform wall heat flux (UWHF) and ii). Non – uniform wall heat flux (NUWHF) boundary condition. A series of heat-loss measurements are carried out in the novel test stand capable of emulating both the boundary conditions, on the indigenous non – evacuated receiver developed for moderate temperature process heat applications. A comparative analysis of natural and forced convection heat loss associated with the bare and glass-covered receiver is performed. The results show that the non – uniform wall heat flux boundary condition has a decisive influence over the forced convection heat loss, especially at higher wind velocities. The work concludes that i) the surface temperature of the receiver associated with natural convection heat loss and subjected to NUWHF boundary condition is1.5– 5% higher than the receiver subjected to UWHF boundary condition. ii) In forced convection mode of heat loss the surface temperature of the receiver is 4–13% higher than the receiver subjected to UWHF. Thus, a more realistic characterization of the thermal behaviour of a non-evacuated receiver for moderate temperature process heat application is possible only by investigating the receiver subjected to non – uniform heat flux distribution. Such a characterization of the receiver will considerably influence the aperture area and thus the cost of the collector to deliver process heat.

A tool to minimize the need of Monte Carlo ray tracing code for 3D finite volume modelling of a standard parabolic trough collector receiver under a realistic solar flux profile

AbstractThe energy collection element of a parabolic trough collector includes a selective coated metallic receiver tube inside an evacuated glass tube. Perpendicularly incident sun light on the parabolic trough mirror aperture is concentrated on the receiver tube highly nonuniformly along its circular direction. This solar energy is collected as thermal energy circulating a suitable heat transfer fluid (HTF) through the tube. This conjugate heat transfer phenomenon under nonuniform heat flux boundary condition is computationally studied applying 3D finite volume (FV) modelling technique of computational fluid dynamics coupled with Monte Carlo ray tracing (MCRT) optical data. The MCRT model simulates the actual flux profile around the receiver tube. Apart from a FV model, this coupled study requires expertise in, and access to, a suitable MCRT code. A combination of polynomial correlations and user‐defined function (UDF) is introduced in this article in order to minimize the need of MCRT codes from subsequent FV modelling of the receiver tube of the Luz Solar 2 (LS2) collector. The correlations are developed from a verified 3D MCRT model, which is equivalent to the local irradiation data as a function of receiver circular location. The UDF includes two algorithms: one to develop solar flux profile from the correlations around the receiver, and the other to calculate heat loss from the receiver. Interpreting the UDF into ANSYS Fluent, a 3D FV model of the LS2 receiver is developed and validated with experimental results. The effectiveness of the UDF as an alternative to MCRT code is verified. The FV model is capable to investigate the heat transfer characteristics of the LS2 collector receiver at different solar irradiation level, optical properties of the collector components, glass tube conditions, HTFs, inserts or swirl generators, collector length, and internal diameter of the tube.

Effect of reduced graphene oxide as nanofluid on solar parabolic trough collector receiver model

The study of reduced graphene oxide as nanofluid with base fluid of volume fraction (10%Vol) was prepared to perform the thermal investigation on solar parabolic trough collector receiver model. The peak intensity of nanoparticle size distribution and crystal structure behaviour was employed by transmission electronic microscopy (TEM) and X-ray diffractometer (XRD) techniques. In order to enhance thermal performance of the receiver model between evacuated and non-evacuated conditions are established. For testing of physical parameters of Reynolds number, friction factor and average Nusselt numbers with fixed magnitude of heat flux at duration of time period. In this evacuated and non-evacuated model, the friction factor and average Nusselt number were slightly decreased for rGO/distilled water and comparatively increased for base fluids. Due to addition of nanoparticles, the thermo-physical parameters of nanofluid had thinner layers of thermal boundary of particle size inside the fluid of pipe wall sections of evacuated receiver model are more efficient heat transfer capability compared to non-evacuated model.

Experimental analysis of a solar cooker with a parabolic trough enhanced with PCM based thermal storage

Experiments are conducted on solar cooker using solar energy. Heat collected by a fluid from the Parabolic Trough Collector (PTC) with the manual Tracking Mechanism(TM) is passed through the Storage Tank (ST). A Phase Change Materials (PCM) in the ST products absorbed the heat in the irregular sunlight and is released constantly for cooking purposes. Based on the observation of PTC and ST, a heat transfer analysis of the Solar Cooker (SC) is carried out considering 0.035, 0.045 and 0.065 kg/sec Mass Flow Rate (MFR) of the heat transfer fluid. At 1 pm, themaximum Heat Gain (HG) of PTC receiver at the Rim Angle (RA) of 82° is found to be 2095 W, 13 KW in ST with a medium of Wastage Engine Oils (WEO). The heat output of the WEO found to be 16% more than that of the water. The efficiency of the newly designed the solar cooker is tested at the MFR 0.035, 0.045 and 0.065 kg/sec along with storage medium. The results of the MFR of 0.035 kg/sec are seen as better than 0.045 and 0.065 kg/sec for the water and WEO medium. Hence the energy extracted is greater. The WEO is seen as more stable with smaller energy losses than the water. Stearic acid (SA) is used for PCM materials.

Investigations on Receiver of Parabolic Trough Collector

The flow pattern and attributes of heat transfer in symmetric outward curved layered corrugated tube has been researched based on Reynolds stress transport (RST) model using numerical simulations. In this study validation of obtained RST modelling results and existing RST modelling results of simulation by Feng-Chen Li has been carried out and results mate well. Based on this, same procedure of RST modelling simulation is applied to investigate detailed pattern of flow and mechanism of heat transfer in proposed model of corrugated receiver tube. In one corrugation of the model, detailed study of velocity, temperature and Reynolds stress distribution for various profiles is done. It is determined that, in proposed model of corrugated receiver tube structure intensity of velocity fluctuation greatly increases, as a result of that there is rise in rate of heat transfer which leads to raise in efficiency of thermal power plant application.

To Maximize Heating Performance of Solar Parabolic Trough Collector by Geometrical Variation Using CFD Analysis

The potential of renewable energy should be investigated. Renewable energy is the energy from natural and unnatural available forms including wind, biomass, solar, and waste heat energy generated through various human activities. Solar energy is an available and clean form of renewable energy used as an alternative to fossil fuel in generating energy. However, the maximum extraction of thermal energy from the sun is most challenging. This study focuses on energy generation using the parabolic trough collector (PTC). This review contains geometrical analysis including the thermal approach of the PTC model, heat transfer, and method of enhancing thermal efficiency on the PTC receiver. So to identify the performance analysis, thermal efficiency, and applications of the solar-powered PTC and the history of PTC evolution. The PTC applications include desalination process, air heating system, power plants, refrigeration, and industrial heating purposes.

Deformation of receiver in solar parabolic trough collector due to non uniform temperature and solar flux distribution and use of bimetallic absorber tube with multiple supports

Present study aims at minimising the risk of bending in receiver of Parabolic Trough Collector (PTC) using double layered absorber held at pillars and mathematical equations are formulated. Tube is modelled for practical scenarios supported by pillars made up of movable structure that can slide to help absorber expand when heated. Ball joints at contact points enable tube to rotate. Equations are validated against the experimental measurements. Effects of placement of conductive material, focal length, PTC width, geometrical imperfections and HTF flow rate on bending and energy losses due to bending are studied. It is found that (i) single layered absorber leads to bending and energy loss of −15.1 mm and 2.3%. Double layered absorber with high conductivity material as inside layer reduces bending/energy loss to −10.0mm/1.0%. However, use of high conductivity as outside layer further reduces bending/energy loss to −6.1mm/0.4%, (ii) change in HTF flow rate from 0.4 kg/s to 1.4 kg/s reduces bending/energy loss from −15.1mm/2.3% to −10.2mm/1.0% for single layered absorber and −6.1mm/0.4% to −4.5mm/0.2% for double layered and (iii) focal length near to 0.7 m reduces bending/energy loss to 0mm/0%.

Energetic end exergetic performance of a parabolic trough collector receiver: An experimental study

In this article, an experimental investigation is evaluated with the aim of assessing the thermal performance of a receiver tube of a parabolic trough collector. The parabolic trough collector is designed, constructed and installed in the Laboratory of Thermal Processes, Research and Technology Center of Energy (CRTEn), Borj Cedria. The thermal performance was carried out using both first and second law of thermodynamics. A detailed energy and exergy analysis was performed to evaluate the thermal performance. Throughout the study, the useful energy gain and the receiver tube exergy transferred to the heat transfer fluid, the energy and exergy efficiency as well as the exergy factor were measured. The measurements were conducted during the months of September and October 2015 at Borj Cedria-Tunisia. The result has shown that the thermal performance is strongly influenced by climatic conditions. The average energy and exergy efficiency are found to be higher under clear sky days than the overcast cloudy sky days. The daily energy efficiency varied between 19.7% and 52.6%. While the daily exergy efficiency varied from 8.51% to 16.34%.

Performance Enhancement of Solar Parabolic Trough Collector Using Intensified Ray Convergence System

Solar Energy is one of the forms of Renewable Energy that is available abundantly. This work is executed on the enhancement of the performance of solar parabolic trough collector using Intensified Ray Convergence System (IRCS). This paper distinguishes between the performance of solar parabolic trough collector with continuous dual axis tracking and a fixed solar parabolic trough collector (PTC) facing south (single axis tracking). The simulation and performance of the solar radiations are visualized and analyzed using TRACEPRO 6.0.2 software. The improvement in absorption of solar flux was found to be enhanced by 39.06% in PTC using dual axis tracking, absorption of solar flux increases by 52% to 200% in PTC receiver using perfect mirror than PTC using black chrome coating.

Numerical optimization and convective thermal loss analysis of improved solar parabolic trough collector receiver system with one sided thermal insulation

Two type of receiver systems currently employed in solar parabolic trough collector technology are evacuated annuli receivers and air filled annuli receivers. While former receiver finds its way into high-temperature grid-acquaintance solar parabolic trough collectors, latter are more inclined towards non-grid solar thermal applications like low-temperature process heat. Evacuated receivers utilize vacuum filled annuli to reduce down the convection losses; this makes them substantially expensive – while prizing them as benchmark among receivers. Contrary, air filled annuli based receivers are relatively less expensive but are sub-par in thermal performance relative to evacuated receivers. This work deals with the air filled receiver system and would try to abridge the economy and efficiency between both types of systems using computational fluid dynamics (CFD) based numerical simulation approach. A heat blocking thermal insulation was tailored and fitted in the sun facing receiver annulus which does not receive concentrated radiation of the Sun, and was simulated for the reduction in convective losses and for favourable circumferential temperature distribution (CTD) around the absorber. Consequently, its convective heat losses were investigated for varying wind speeds and mass flow rates of heat transfer fluid (HTF) and were compared with mainstream air filled annuli receivers. Simulation results are compared with experimentation in which wind velocity was in a range of 0.43–4.99m/s. It has been found that glass envelope temperature decreases with increase in wind velocity which directly insinuates the decrease in convection losses around glass envelope. These comparative implications could be served as a point of reference to develop solar parabolic trough collector for small scale process heat applications in India.

Heat transfer enhancement in a parabolic trough solar receiver using longitudinal fins and nanofluids

In this paper, we present a three dimensional numerical investigation of heat transfer in a parabolic trough collector receiver with longitudinal fins using different kinds of nanofluid, with an operational temperature of 573 K and nanoparticle concentration of 1% in volume. The outer surface of the absorber receives a non-uniform heat flux, which is obtained by using the Monte Carlo ray tracing technique. The numerical results are contrasted with empirical results available in the open literature. A significant improvement of heat transfer is derived when the Reynolds number varies in the range 2.57×104 ≤ Re ≤ 2.57×105, the tube-side Nusselt number increases from 1.3 to 1.8 times, also the metallic nanoparticles improve heat transfer greatly than other nanoparticles, combining both mechanisms provides better heat transfer and higher thermo-hydraulic performance.

Multi-scale numerical analysis of flow and heat transfer for a parabolic trough collector

This paper numerically investigated the coupled flow and heat transfer of a parabolic trough collector (PTC), with the non-uniform heat flux boundary condition on the absorber wall and the rarefied gas effects in the annular vacuum gap being taken into consideration. A fully coupled cross-sectional heat transfer model is established with Direct Simulation Monte Carlo (DSMC) method for the rarefied gas flow and heat transfer in the vacuum annual gap. The PTC tube efficiency can be obtained from the above simulation for a given HTF temperature. Such simulation is conducted for several specified HTF temperature and different efficiency data are obtained. These data are fitted by an equation. This equation is then used to advance the HTF temperature in the axial direction. In such a way a simplified 3D model for the design of a PTC receiver is obtained. Cross-sectional simulation results show that when the gas pressure is less than 0.1Pa further decrease in pressure makes no further contribution to reduce the heat loss. The effects of periphery non-uniform distribution of heat flux, coating material emissivity, envelope diameter and HTF inlet velocity on the PTC efficiency are discussed. An operation variant is proposed by using the 3D model by which the total PTC tube length can be reduced for a given thermal load.

Experimental investigation of porous disc enhanced receiver for solar parabolic trough collector

In this article, experimental investigation of 15 m2 solar parabolic trough collector with porous disc enhanced receiver is carried out according to ASHRAE 93-1986 test procedure. Six different receiver configurations are developed and investigated to compare their performance. The performance of solar parabolic trough collector with two conventional and four porous disc receivers is characterized in terms of time constant, collector acceptance angle, peak performance, daily performance and heat loss tests. The tests are carried out for wide range of flow rates (100 L/h–1000 L/h) and weather conditions. Based on experimental investigation, the time constant of the parabolic trough collector is varied from 70 s to 260 s for different receiver configurations. The collector acceptance angle is determined for both un-shielded tubular receiver (USTR) and shielded tubular receiver (STR) as 0.58° and 0.68° respectively. The collector efficiencies are obtained as in the range of 63.9%–66.66% under ASHRAE standard test condition. Off-Sunset heat loss test is conducted to determine the steady state heat losses from the parabolic trough collector receiver. The heat losses from the parabolic trough collector are in the range of 455 W/m2–1732 W/m2 for average fluid temperature of Tamb + 30 °C. Stagnation temperature of the collector is obtained as 258 °C and 312 °C respectively for USTR and STR corresponding to direct normal insolation (DNI) of 786 W/m2 and 761 W/m2. Based on the above analysis, the porous disc enhanced receiver improves the performance of the parabolic trough collector significantly and it can be used effectively for process heat applications.

A detailed thermal model of a parabolic trough collector receiver

Parabolic trough collectors are made by bending a sheet of reflective material into a parabolic shape. A metal black pipe, covered with a glass tube to reduce heat losses, is placed along the focal line of the collector. The concentrated radiation reaching the receiver tube heats the fluid that circulates through it, thus transforming the solar radiation into useful heat. It is sufficient to use a single axis tracking of the sun and thus long collector modules are produced. In this paper a detailed thermal model of a parabolic trough collector is presented. The thermal analysis of the collector receiver takes into consideration all modes of heat transfer; convection into the receiver pipe, in the annulus between the receiver and the glass cover, and from the glass cover to ambient air; conduction through the metal receiver pipe and glass cover walls; and radiation from the metal receiver pipe and glass cover surfaces to the glass cover and the sky respectively. The model is written in the Engineering Equation Solver (EES) and is validated with known performance of existing collectors and subsequently is used to perform an analysis of the collector we are going to install at Archimedes Solar Energy Laboratory at the Cyprus University of Technology.