Linear Fresnel Collector Research Articles

The Canal Top Solar Power Generation Project

Abstract: Solar energy is one of the most abundant sources of renewable energy for the future. This solar energy can be uprooted by PV system. Negative environmental impact of reactionary energy consumption highlights the part of renewable energy sources and give them a unique occasion to grow and ameliorate. Among renewable energy sources solar energy attract further attention and numerous studies have concentrated on using solar energy for electricity generation. Then, in this study, solar energy technologies are reviewed to find out the stylish option for electricity generation. Using solar energy to induce electricity can be done either directly and laterally. In the direct system, PV modules are employed to convert solar irradiation into electricity. In the circular system, thermal energy is exercised employing concentrated solar power (CSP) shops similar as Linear Fresnel collectors and parabolic trough collectors. In this design electricity generation in Pune from solar energy by furnishing solar panels on top of conduit is bandied. And we prepare model for the design in Pune. We also bandied about the developments in Pune due to this solar power design and how the electricity is distributed in Pune and how the conduit water is used for agrarian purposes. This solar power generation from the top face of conduit design has several benefits similar as16.2 million units of power generated annually, 90 million liters of water is conserved annually, 25 acres of land conserved, lower algae growth in the conduit water, minimize evaporation from conduit, produce Eco-friendly power using solar panels as a cover and save land

Modelling and analysis of a novel production process of high-pressure hydrogen with CO2 separation using electrochemical compressor and LFR solar collector

Hydrogen as an alternative fuel has a very promising future. Using renewable solar energy to produce green hydrogen is one of the most interesting approaches due to its environmental friendliness. In this study, a novel system configuration is designed and studied that includes electrochemical compressor (EHC), hybrid thermionic-thermoelectric converter (TIG-TEG), and a solar linear Fresnel collector system (LFR). The EHC can produce a hydrogen product at a high pressure with a high purity. Moreover, using a 50/50 H2–CO2 feed a pure CO2 byproduct can be separated from the process. A detailed mathematical modelling considering several key phenomena of the EHC and the TIG-TEG converter is presented with a full variable list that haven't been reported to such extent yet. Simulation is performed in MATLAB and a sensitivity analysis to assess the performance of each subsystem and the overall system is conducted. Results show that several operating conditions and state performances have the same end-results in terms of hydrogen production rate. Further, it is found that the LFR thermal efficiency of 61.67% and a solar fraction of 73.03% can be achieved. Also, maximum output power and efficiency of the hybrid converter as 19.85 kW and 44.76% is realized. As such, 93 units of EHC at a current density of 1 A/cm2 could be operated to produce hydrogen of 50 atm pressure at a rate of 2.17 kg/h.

Direct gas heating in linear concentrating solar collectors for power and industrial process heat production: Applications and challenges

AbstractParabolic trough collectors and linear Fresnel collectors are mature technologies for power production, and they are being recently applied to provide solar heat for industrial needs. Conventionally, they use a liquid as heat transfer fluid, either thermal oil or water, to carry heat from the receivers up to the point of conversion or delivery. Although liquids offer excellent thermal properties, they show technical limitations, besides environmental concerns, which have encouraged the research on alternative solutions. This work reviews the main research works on the use of gases as heat transfer fluid in linear concentrating collectors, including solar power and heat production, highlighting the potential applications and technical challenges. The review indicates: first, gases offer potential to replace liquids, and second, there is a need for more research and development to define the best technical compromises to reach practical application in every sector.This article is categorized under: Sustainable Energy > Solar Energy Energy and Power Systems > Energy Infrastructure

Investigation of a Linear Fresnel solar collector (LFSC) prototype for phosphate drying

Drying is an energy intensive process, which requires a high amount of thermal and electrical energy. To respond to that challenge, this paper proposes an innovative phosphate dryer environment friendly. The idea is to exploit the Linear Fresnel Solar Collector (LFSC) in the drying process. A laboratory scale prototype was designed and constructed based on a detailed theoretical and optical study. The numerical results prove that the designed prototype admits a significant optical efficiency which can reach values higher than 0.7 from May to July. An adjustment of LFSC prototype mirrors by laser beam allows good optical performances suitable for phosphate drying. The experimental results showed that the residual humidity of the dried phosphate was in the order of 0.02 kg water/kg dry matter in the LFSC process and 0.07 kg water/kg dry matter in the open air process, after 04 h 40 min. The drying process using LFSC has reached international phosphate marketing standards. Based on 100 m2 LFSC aperture area, the yearly provided thermal energy was 59,766 kWh, the largest quantities of dried phosphate are obtained during the summer with a maximum of 43 tons in July and the dodged CO2 emissions are about 38,255 kg.

Influence of topography on the optical performances of a Fresnel linear asymmetrical concentrator array: The case of the eLLO solar power plant

Solar field orientation and inclination are variables that significantly influence the optical performance over the year of Linear Fresnel Collector (LFC). The usual field configuration is a flat north-south (NS) orientation, however, the future development of the LFC sector, for example for solar heat for industry, could more often impose the land choice and therefore the solar field configuration. To study the influence of such configuration on a solar field optical performance, a ray-tracing model was used to evaluate the LFC optical performance for each solar position and a consistent methodology was developed to evaluate the solar position in the module reference system. This method allows studying the optical performance of any LFC array configuration. The paper first looks separately at the influence of orientation and tilt imposed by the topography of the eLLO project, then focuses on the eLLO solar power plant case study. The results of eLLO's solar line simulation showed an increase of 1.6% in annual absorbed energy compared to NS implementation, which is the best orientation for the localization. In conclusion, the design and implementation of modular LFC array can be adapted to a wide range of terrains and can even take advantage of this constraint.

A GIS-AHP approach for determining the potential of solar energy to meet the thermal demand in southeastern Spain productive enclaves

In this work, the potential of southeastern Spain to host solar thermal plants to meet the heat demands of its industrial enclaves is assessed and presented. For this, the generation of thermal energy for industrial uses in the medium temperature range is estimated, with special emphasis on those areas not connected to the thermal energy distribution networks. This region has been selected due to its high availability of solar resources, while forming a geographic area that presents numerous agrifood industries. These facilities, according to their temperature range heat demands for boiling, pasteurizing, and other food-related processes, are one of the best-suited sectors for the application of medium-temperature solar collectors, both parabolic trough and linear Fresnel. A Geographic Information System and the Analytic Hierarchy Process Method have been used for information management and decision making, respectively. A geographic database was built using layers provided by different information sources on climate, land characteristics and use, industrial activity, and energy infrastructures, including the distance to natural gas distribution pipelines as a specific criterion for decision making. The final result translates into a geographic suitability scale, which revealed that about 5%(1482km2) of the total territory in southeastern Spain is highly suitable for the future development of productive enclaves fed by solar thermal installations, where it is estimated that the energy demand could be met in 42%(9.5TWh/y) with parabolic trough and 65%(14.7TWh/y) linear Fresnel collectors in areas with a score since 7 points.

Thermal and flow performance analysis of a concentrated linear Fresnel solar collector with transverse ribs.

This article deals with the impact of including transverse ribs within the absorber tube of the concentrated linear Fresnel collector (CLFRC) system with a secondary compound parabolic collector (CPC) on thermal and flow performance coefficients. The enhancement rates of heat transfer due to varying governing parameters were compared and analyzed parametrically at Reynolds numbers in the range 5,000-13,000, employing water as the heat transfer fluid. Simulations were performed to solve the governing equations using the finite volume method (FVM) under various boundary conditions. For all Reynolds numbers, the average Nusselt number in the circular tube in the CLFRC system with ribs was found to be larger than that of the plain absorber tube. Also, the inclusion of transverse ribs inside the absorber tube increases the average Nusselt number by approximately 115% at Re = 5,000 and 175% at Re = 13,000. For all Reynolds numbers, the skin friction coefficient of the circular tube with ribs in the CLFRC system is larger than that of the plain absorber tube. The coefficient of surface friction reduces as the Reynolds number increases. The performance assessment criterion was found to vary between 1.8 and 1.9 as the Reynolds number increases.

A Review of Linear Fresnel Collector Receivers used in Solar Thermal Technology

Linear Fresnel collectors (LFC) have, among the four technologies of concentrating solar power (CSP), the simpler technology. They have a one axis sun tracking, plane mirrors and a fix receiver. All these elements make them the most suitable for small scales CSP plants adapted to rural area of the Sub-Saharan region. The receiver is an important part of the LFC. There is a wide variety of receivers that differ in the shape of the absorber: mono-tube, multi-tube, plane. The shape of the secondary concentrator or its absence allows to categorize the receivers in a butterfly, compound parabolic concentrator, segmented parabolic secondary concentrator or trapezoidal receiver. Vacuum mono-tube receivers have heat losses between 200 W/m and 270 W/m at an absorber temperature of 350°C. A mono tube receiver at partial vacuum losses more than 350 W/m at 350°C. The lowest heat losses of a multi-tube receiver with a trapezoidal secondary concentrator can reach 500 W/m at an absorber temperature of 350°C. This paper discusses a comparative study of existing receiver designs in order to find the most suitable for rural areas in the sub-Saharan region, i.e. easy to design by hand and low cost. Although they do not have the best thermal performance, trapezoidal receivers with a black-painted copper multi-tube absorber and a glass cover seem to be the most suitable.

Measuring Concentrated Solar Radiation Flux in a Linear Fresnel-Type Solar Collector

Linear Fresnel solar collectors are a promising and emerging solution to contribute to renewable heat supply in industrial processes with thermal energy demand in the medium temperature range (<250 °C). An innovative linear Fresnel collector (LFC) prototype has been designed, patented, and built at the Plataforma Solar de Almería (PSA), Spain. This work presents the applied methodology, experimental device, and results obtained in the measurement of the flux density of concentrated solar radiation in the focal plane of the solar collector. The experimental results confirm that an average flux density of (9.8 ± 0.6) kW/m2 was obtained with a direct normal solar irradiance of (870 ± 10) W/m2 in tests performed in May 2002, which is a result similar to that obtained in optical simulations of the system.

Thermal Performance Analysis of a Linear Fresnel Concentrating Solar Collector Absorber Tube

Linear Fresnel solar collectors are suitable for a wide range of applications, which include steam generation for power generation, industrial process heat, solar cooling, institutional and domestic hot water production etc. The thermal performance of a linear Fresnel solar collector absorber tube was investigated in this study for different fluid mass flow rates, heat flux intensities, heat transfer fluid inlet temperatures, ambient air temperatures and external loss heat transfer rate. Turbulent flow liquid water heat transfer fluid and uniform circumferential heat flux distribution boundary were considered under steady-state conditions. The fluid flow was considered incompressible. This study was limited to a first order model approximation for thermal performance of a linear Fresnel solar collector absorber tube. The heat transfer fluid and absorber tube material properties were considered constant and independent of temperature. The results indicated that the absorber tube outlet heat transfer fluid temperature decreased with an increase in the Reynolds number and increased with the heat flux intensities. Thermal efficiency increased with an increase in the heat transfer fluid mass flow rate and however, decreased with increase in pressure drop and the consequent pumping power requirement. It was also found that the thermal efficiency of the collector decreased with an increase in the fluid bulk inlet temperature and decreased with an increase in the external loss heat transfer rate.

Optical performance comparison of two receiver configurations for medium temperature Linear Fresnel Collectors

Linear Fresnel collectors are good candidates to lower the use of fossil fuels in the built environment and in the industry, due to their compact nature and adaptability. In addition, the technology shows large margins for improvement, in terms of efficiency capital and operational expenditures. The present study presents a new atmospheric double tube absorber, which fully explores non-imaging optics design. An existing LFR system with a second stage concentrator consisting of an evacuated tube with an associated secondary parabolic reflector, is compared with a novel model adopting the same LFR primary field but a new second stage concentrator, which achieves a much wider acceptance angle. It is shown that, beyond a better performance, the novel proposed solution provides simpler maintenance, as in cleaning and parts’ replacement, and a reduced cost, as it includes cheaper standard components. The study was conducted in ray-tracing environment with the Tonatiuh++ software, which is able to directly implement non-imaging optics configurations via analytic equations. The present study is centred on the optical performance of the collector. The quantitative comparison demonstrates that the annual yield of the novel model is increased at least by 8.3% while the cost per metre of the receiver is decreased by 45%.

Impacts of biomass hybridization on exergetic sustainability of a solar organic Rankine cycle power plant

Due to the low thermo-economic performance of solar ORC plants, several studies are ongoing to investigate the potential merits/demerits of biomass hybridization as a retrofit. Although many of such studies have examined the technical and economic viabilities of various hybrid solar-biomass concepts, due attention has not been directed to the area of their sustainability based on the Second Law of Thermodynamics. This study was aimed at investigating the potential effects of biomass hybridization on the exergetic sustainability of an organic Rankine cycle (ORC) power plant. Design data of an existing solar ORC plant currently operational at Ottana (Italy) were employed for analysis. The referenced ORC plant is rated at about 630 kWe, powered at the moment solely by a concentrated solar power (CSP) field, which integrates linear Fresnel collectors with two-tank thermal energy storage (TES) device. Five different exergetic sustainability indicators were employed in this study to assess the aforementioned ORC plant when fed by hybrid solar-biomass energy resources. Results showed the hybrid plant's destruction factor (DF), exergetic sustainability index (ESI), environmental effect factor (EEF), improvement potential rate (IPR), and recoverability ratio (RECR) of 89.40%, 0.119, 8.435, 4744.8 kW, and 0.89, respectively. Additionally, a comparison of the solar-only and the hybrid solar-biomass schemes revealed that biomass hybridization would improve the exergetic sustainability of the ORC plant. Nevertheless, the high value of IPR obtained suggests that ample opportunities would yet exist to further enhance sustainability indices of the studied ORC plant post biomass hybridization. In sum, biomass hybridization of the solar ORC plant considered in this study would enhance sustainability performance but more opportunities would yet exist to further optimize the system.

Control Strategies Applied to a Heat Transfer Loop of a Linear Fresnel Collector

The modelling of Linear Fresnel Collectors (LFCs) is crucial in order to predict accurate performance for annual yields and to define proper commands to design the suitable controller. The ISO 9806 modelling, applied to thermal collectors, presents some gaps especially with concentration collectors including LFCs notably due to the factorisation of the incidence angle modifiers and the fact that they are considered symmetric around the south meridian. The present work details the use of two alternative modellings methodologies based on recorded experimental data on the solar system installed at the Cyprus Institute, in the outskirts of Nicosia, Cyprus. The first modelling is the RealTrackEff, which is an improved ISO9806 modelling, and the second is constructed using the CARNOT blockset in MATLAB/Simulink. Both models include all the elements of the heat transfer fluid loop, i.e., mineral oil, with a tank and a heat-exchanger. First, the open loop’s studies demonstrated that the root mean square on temperature is 1 °C with the RealTrackEff; 2.9 °C with the CARNOT and 6.3 °C with the ISO9806 in comparison to the experimental data. Then, a PID control is applied on the experimental values in order to estimate the impact on the outlet temperature on the absorber and on power generation. Results showed that the error on the estimation of the heat absorbed reaches 32%.

Comparative Study on Heat Flux and Temperature Distribution Performance of Linear Fresnel Collector Based on Uniformity Index

Comparative Study on Heat Flux and Temperature Distribution Performance of Linear Fresnel Collector Based on Uniformity Index

Comparative evaluation of Integrated Solar combined cycle plant with cascade thermal storage system for different heat transfer fluids

The existing conventional combined cycle power plant(s) are generally not getting the schedules for supply of power because of the high price of Natural Gas and are forced to remain idle or to run on part load. On the other side, the focus is on the capacity addition of power generation units based on the alternate sources mainly solar to counter the ill effects on environment through fossils fuel-based plant(s). In such a scenario, the combined cycle power plant(s) with its integration with solar (ISCC) can pave the way forward to provide an optimal solution to tap most of the power generation through solar power and to ensure grid stability through utilising the installed combined cycle power plant(s) at part or full load. It will be a win-win situation for solar plants as well as combined cycle power plants. This study presents an integration of Linear Fresnel collector solar system and latent heat cascade storage system with a 328.10 MW combined cycle power plant of north India for operating it as integrated solar combined cycle (ISCC). The present work discusses the configurations of integration of solar power generation cycle with the combined cycle power generation and presents the analysis of the performance of these integration configurations including the operation of gas turbine(s) at full load or part load. A MATLAB code is used for simulation to analyse the performance of ISCC by varying direct normal irradiation at different part-load condition of gas turbine with different heat transfer fluids such as water and molten salt, then also compare the performance of latent heat cascade thermal storage system with oil & molten salt as HTF. The effect of cascade thermal storage has also been analysed on the plant performance. The efficiency of ISCC with molten salt as HTF is 50.87% which is more than with water as HTF by 1.51%. The present study also brings out the saving of the fuel to figure out the financial benefit. However, the financial model has not been developed in the present work due to the dynamics of the price of natural gas internationally. The study also presents the analysis of the enhanced fuel-saving ratio and reduced emissions.

Analysis of Light Concentration Error and Compensation Algorithm of Linear Fresnel Collector

Analysis of Light Concentration Error and Compensation Algorithm of Linear Fresnel Collector

Realistic Simulation Tool for practical Analysis of Solar Cooling Thermal Systems driven by Linear Fresnel Collectors

The objectives of this study were to develop a realistic simulation tool to analyze solar thermal cooling systems driven by Fresnel collectors and carry out a case study in which the performance of a solar cooling system of 190 kW located in Riyadh is simulated to demonstrate the functionality and potentiality of the developed tool. This tool is based on an integrated mathematical model that considers the ambient conditions, the thermal loads of the building, the pre-sizing data of each of the components of the system and the simultaneous interaction among them, to conduct a realistic, simple, and precise analysis. A demonstrative simulation example was performed. During the month of July, with a solar opening area of 704 m2 and a tank of 35200 L, a total amount of 47,5 MWh of cooling energy was obtained, with a reduced contribution of the auxiliary system (5,6 MWh) and a minimum number of solar collector system deactivation hours (0,7 %). The daily COP of the absorption machine remained above 0,69. The obtained results from the case study with the simulation tool allowed to verify its functionality, capabilities and correct operation to carry out hourly and parametric studies of this type of systems.

Comparative exergoeconomic evaluation of integrated solar combined-cycle (ISCC) configurations

This paper provides an exergy, economic, and exergoeconomic comparative analysis for the three most promising solar thermal technologies of integrated solar combined-cycle systems: direct steam generation linear Fresnel collectors, solar power tower, and oil parabolic trough collectors. The exergetic analysis shows that configurations using Fresnel collectors result in the highest exergetic efficiencies (44.1%), while the configuration using a solar tower leads to the lowest efficiency of 33.2%. Integrating the solar field into the high-pressure part results in higher efficiencies for day operation. However, this limits the steam cycle to benefit from higher pressure levels, especially during night operation, as the cycle has to operate on the same design pressure level to avoid possible part-load losses. Findings of the economic analysis show that sharing the same power block of the combined-cycle plant results in a significantly lower incremental specific investment cost for concentrated solar power (2545 $/kW) that helps new installations at moderate investments, leading to steeper learning curves of the technology. Configurations using solar collectors with direct steam generation produce electricity at the lowest price of 36.75 $/MWh. The configuration using oil parabolic trough produces electricity at the highest price (38.62 $/MWh).

Transient simulation of hybridized system: Waste heat recovery system integrated to ORC and Linear Fresnel collectors from energy and exergy viewpoint

Industrial waste heat often has a discontinuous flow with considerable fluctuations in both mass flow rates and temperature. Besides, there are challenges associated with the reliability of solar power due to its intermittent nature. The present study has prepared a continuous and steady heat load for the Organic Rankine Cycle (ORC) in two sectors. The first sector, waste heat recovery system (WHRS) of low-temperature gases in an electric arc furnace (EAF) integrated to ORC, secondly the hybrid of WHRS and ORC along with linear Fresnel collectors (LFC). Steam accumulators as thermal energy storage (TES) stabilize the thermal power fluctuations in both WHRS and LFC. The steam accumulator thermodynamic model was simulated in terms of the non-equilibrium thermal model for the liquid and vapor phases. The behavior of the hybridized WHRS was presented with three solar multiples of 1.8, 2.1, 2.8. Constant and continuous thermal power for the ORC was provided with a solar multiple of 2.8 in a full day (20th August) with an average net power of 1252 kW. It should be noted that the transient state of the system was examined from the energy and exergy viewpoint. The thermal and exergy efficiencies of the WHRS integrated with the ORC were 16.4% and 27.1%, respectively. However, the hybridized WHRS concerning thermal and exergy efficiencies were 12.3% and 16.35%, respectively. Moreover, the exergy destruction rate for all system components was calculated, and the maximum value was found to occur in the LFCs.

Calculation of the incidence angle modifier of a Linear Fresnel Collector: The proposed declination and zenith angle model compared to the biaxial factored approach

Since their first appearance as a contribution by Professor Francia at the University of Genova, Italy, the Linear Fresnel Collectors (LFC) demonstrated to be an engineering efficient technology for medium to high temperature solar applications. The strength of the LFC concept is related to the simple mirror motion law, to the compactness of the mirror fields (power to land surface ratios), to the lowest resistance to wind, to the system intrinsic scalability. To perform reliable LCOE analyses, robust performance simulation tools are needed. The Authors developed to this aim a 3D ray-tracing model, able to account for shading, blocking, and end effects as a function of LFC geometry, including primary and secondary mirror curvatures. In this paper, a new approach is implemented to reduce huge yearly ray-tracing datasets and provide very compact analytical equations for fast hourly performance simulations. The present model introduces new Incidence Angle Modifier (IAM) correlations based on the declination and zenith angles. The new model demonstrated to fit subhourly 3D ray-tracing data all year long with an overall error lower than 1.5%, well below the best IAM factored models here compared as a general criticism to the biaxial factored approach related to Fresnel applications.