Parabolic Trough Collector Technology Research Articles

Energy, Economic and Environmental (3E) Analysis for an Optimal CSP Technology Integration in Morocco

Among the existing solar technologies, Concentrating Solar Power (CSP) stands out as the most efficient and adaptable option for base load applications, primarily due to its thermal storage capabilities. However, despite its potential, the implementation of this technology still lacks competitiveness compared to Photovoltaic (PV) systems. Therefore, optimizing the plant components and operational factors becomes crucial for its cost-effective utilization, particularly in the desert regions of Morocco. Hence, the objective of this study comprised two main aspects: first, to conduct a parametric analysis aimed at selecting the optimal configuration for a parabolic trough collector (PTC)-based power plant suitable for the Moroccan context. Subsequently, an environmental analysis was performed to assess the impact of soiling on the plant operation. This step aimed to refine the precision of the techno-economic analysis and enhance the project’s bankability. High-quality in situ meteorological data and soiling measurements were utilized for these analyses. Furthermore, to ensure the reliability of the results, the results from the employed simulation tool were validated against real data obtained from an operational power plant. The results indicate that Morocco holds significant potential for the integration of large-scale CSP plants. A capacity of 1 MW utilizing PTC technology could yield an annual electricity production of up to 33 GWhe, with a levelized cost of electricity (LCOE) estimated at 0.1465 EUR/kWh. However, accounting for soiling effects in the yield analysis, which is recommended for precise yield calculations, revealed a decrease in the annual production to 28 GWhe for the same 1 MW capacity. This reduction represented a 20% loss from the nominal conditions, resulting in a corresponding increase in electricity cost by 30.6 €/MWh.

Harnessing solar power in industry: Heuristic optimisation design and transient thermal modelling of parabolic trough solar collector networks

This study presents the development of a transient model for designing and optimising parabolic trough solar thermal plants for industrial processes. The model is validated against published experimental data and other models from the literature. A heuristic optimization methodology based on Particle Swarm Optimization (PSO) to maximise the Present Value of the Life Cycle Energy Savings (PVLCES) is employed. This methodology is applied to three case studies. The results highlight the versatility of PTC (parabolic trough collector) technology in handling a wide range of temperatures. Additionally, the study reveals the optimal PTC aperture width dimensions that maximise the capture of solar thermal energy while increasing the solar fraction. Specifically: For low-temperature processes, the optimum aperture width is 5.0 m; in medium-temperature processes, the optimum aperture width increases to 5.5 m; for high-temperature applications, the optimal value is 5.8 m. Finally, the optimised networks achieve the following heat load-to-area ratios: Low-temperature applications: 0.57 kW/m²; medium-temperature applications: 0.58 kW/m²; high-temperature applications: 0.6 kW/m².

Enhancing the efficiency of solar parabolic trough collector systems via cascaded multiple concentration ratios

Solar parabolic trough collector (PTC) technology is clean and economical. However, PTC technology suffers from relatively low optical and thermal efficiencies at high operating temperatures and concentration ratios (CRs). In this work, a novel strategy for cascadingly using solar collectors with multiple concentration ratios in one collector loop is proposed to reduce optical losses and improve the overall performance of the PTC system. Two systems were studied for implementation of the proposed strategy: an ideal system employing multiple optimal CRs in distinct collector loop sections and a multisection system employing multiple practical CRs. An integrated optical model and two-dimensional heat transfer model based on finite volume and radiation heat transfer methods were developed in this study. These models proved to be highly accurate in estimating the thermal properties of solar collectors. At operating temperatures between 293 and 393 °C, the optical efficiency of the multisection system was 6.7% higher than that of a conventional system with a single CR. Under the same conditions, the thermal efficiency was improved by 4.5%. This work is anticipated to provide a reference for solar collector design and a new avenue for enhancing the overall efficiencies of PTC systems.

Comparative Analysis of Transient Thermodynamic Performance for the Parabolic-Trough Photothermal Conversion Technology

The intermittent nature of solar energy poses a great challenge to the parabolic trough collector (PTC) technology. Although PTC technology is mature in application, its thermodynamic performance in transient processes is in need of a more comprehensive understanding. Here, a transient photothermo-hydraulic model of a parabolic-trough collector loop (600 m) was established with the finite volume method (FVM). A comprehensive comparative analysis for the transient photo-to-thermal characteristics (transient entropy generation and thermal-exergy efficiency) of PTC loop under a main weather disturbance [direct normal irradiance (DNI)], main control parameter (the mass flow rate of the heat transfer fluid mHTF), and geometry-dependent parameters (the collector width a and the absorber tube diameter douter) was carried out. The research shows that increasing DNI increases the entropy generation rate of each part of the absorber tube (up to 45.52%) and decreases the energy and exergy efficiency during the transient process, and vice versa. Transient entropy generation can be reduced by regulating the operating parameters (increase mHTF rapidly) and changing the geometric parameters (a or douter) of PTC (up to 87.58%, 38.03%, and 32.92%, respectively). Moreover, the influencing mechanism of mHTF (a or douter) on the transient entropy generation of the absorber tube is different from that in steady state. The transient thermodynamic response analysis is of great significance to the control and design optimization of PTC loop in the actual system.

Modeling and performance analysis of solar parabolic trough collectors for hybrid process heat application in Kenya’s tea industry using system advisor model

Among the Concentrated Solar Collector (CSC) technologies, Parabolic Trough Collector (PTC) is the most mature and commercialized CSC technology today. Currently, solar PTC technology is mainly used for electricity generation despite its huge potential for heating, especially in industrial process heat (IPH) applications. Though the technology is well-developed and successfully used in many developed countries, there is barely any development in Kenya. This paper studies the techno-economic feasibility of a solar PTC-assisted tea drying process in one tea factory that currently relies on biomass for process heat, in the tea producing area of Kericho, Kenya. The plant integrating parabolic troughs is modelled and a yearly simulation performed using System Advisor Model (SAM) software. The weather data are derived from ground measurements at Kericho meteorological weather station. SAM is used to model the impact of the principal design parameters, i.e., solar multiple (SM), thermal energy storage (TES) and hybridization percentages, on solar–biomass plant configurations, and to reveal the optimum case. The studied impacts are linked to the annual energy production and the optimal size which minimizes the levelized cost of heat (LCOH). Analysis of monthly variations of energy production by the solar PTC reveals that even when the solar system is designed to its maximum capacity (SM of 3 and TES of 24 h), some months will still require hybridisation with biomass to fully meet the energy demand. TES must also be incorporated in the solar PTC design to maximise on energy production. The hybrid solar–biomass plant with TES provides optimal performance when SM is 1.8 and TES is 24 h. This results in LCOH of 1.85 US cents/kWh, which is 25% cheaper than using biomass only as is the current practice. Furthermore, integration of solar PTC has a positive impact on carbon footprint and considerably reduces annual greenhouse gas (GHG) emissions by 9817 tons of CO2-eq, and annual fuel wood consumption by 16,462 m3 (equivalent to 23.51 acres of mature grown trees).

A comparative study between two different techniques of solar integrated systems

• Integrated solar system based on SPT offers the best annual thermal performances. • The solar power tower allows HRSG to operate in fired mode. • Ganapathy’s method is adopted to evaluate the steam mass flow generation. • Noticeable enhancement in solar-to-electric efficiency with a value of about 21%. • ISCC saves about 20.12 million $ of fuel and 0.5 million ton of CO 2 during 30 years. A comparative study between two techniques of solar integration in Integrated Solar Combined Cycle system power plant in terms of thermal performances and economic assessment is carried out in this work. The first system power plant is based on parabolic trough collector technology where solar heat is introduced in the steam power block as a latent heat and the second system runs with a solar power tower technology. The latter integrates solar thermal energy as a sensible heat to heat up the flue gases from the gas turbine till the fired temperature before entering the heat recovery steam generator. Thermodynamic investigations show high thermal performance for both thermal power plants, but the system plant with solar tower exhibits the best annual performances efficiency value of about 57.2%. Furthermore, in terms of solar conversion to electricity, the plant based on solar tower reveals noticeable enhancements; almost constant values during the year of about 20.8% have been registered. In terms of economic analysis, both power plants show approximately the same Levelized cost of energy of 0.0395 $/kWh and 0.0355 $/kWh for the plant based solar tower and that based parabolic collector respectively.

Optimization of solar-coal hybridization for low solar augmentation

This work presents a process to determine the preliminary optimal configuration of a concentrating solar power-coal hybrid power plant with low solar augmentation, and is demonstrated on a regenerative steam Rankine cycle coal power plant in Castle Dale, UT, USA (average DNI of 542 W m−2). A representative plant model is developed and validated against published data for a coal power plant. The simplifications that lead to the representative model from a coal power plant model include combining multiple feedwater heaters, combining turbines, and using a mass-average calculation for extraction steam properties. Comparing net power generation and boiler heating estimates from the representative model to the benchmark power plant, the representative model predictions are accurate to within ±2.5% of the accepted value. Methods for quantifying solar resource based on geography and simulating a concentrating solar power field arrangement are provided and the solar contribution to electrical power output is estimated using an exergy balance. A financial model is also included to estimate the solar marginal levelized cost of electricity and payback time using a cash-flow analysis. A multi-objective optimization routine is then employed to determine the optimal configuration using the models described in this study.It is shown that a solar augmentation of >3% of boiler heating is required for a hybrid design to be considered thermodynamically feasible. However, as the augment fraction is increased, the financial benefit from fuel savings is insufficient, without a carbon tax, to offset the higher capital cost. Optimization results, constrained to a maximum solar field size of 20 ac, are also provided assuming a common carbon tax value (16 USD sh.tn.−1). The resulting optimal design for the Castle Dale Plant with a carbon tax and no premium indicates the use of parabolic trough collector technology at an augment fraction of k=9% to bypass feedwater heater 6. The resulting marginal solar levelized cost of electricity is 9.5 x 10-4 USD kWh−1 with an estimated payback time of 25.2 years. With a green energy premium price of 0.018 USD kWh−1 and no carbon tax, the payback time reduces to 3.9 years. This process can be applied to a subcritical Rankine cycle coal power plant for which operating data and meteorological data are available to evaluate preliminary hybridization feasibility.

MoS2-based nanofluids as heat transfer fluid in parabolic trough collector technology

Concentrating solar power is becoming one of options for producing energy to replace conventional polluting energy sources. However, improving the efficiency and reducing the cost of technologies based on this type of energy to make it more competitive is still a work in progress. This study proposes replacing the thermal oil used as the heat transfer fluid in the absorber tubes of parabolic trough solar collectors (PTCs) with nanofluids based on spherical molybdenum disulphide nanoparticles with the aim of improving the thermal efficiency of concentrating solar power plants. The colloidal stability of the nanofluids was verified by Ultraviolet–Visible spectroscopy, Zeta potential and Dynamic Light Scattering monitoring. The presence of spherical MoS2 nanoparticles resulted in an increase of up to 13% in specific isobaric heat and 6% in thermal conductivity compared to thermal oil. Finally, the efficiency of parabolic trough solar collectors was estimated to increase by 5%, which also favours the decrease of pumping power and the elimination of selective coatings on the absorber tube. To our knowledge, this is the first time that MoS2-based nanofluids are tested as heat transfer fluids in PTCs analysing its implementation in the solar energy application.

A Techno-Economic Analysis of Parabolic Trough Collector (PTC) and Solar Power Tower (SPT) as Solar Energy in Malaysia

Malaysia receives an annual average of 2200 hours of solar radiation, making her abundant renewable resources to generate electricity. Thus, a good planning is required to manage the resources efficiently and to utilize the abundant resources fully. Concentrating solar power (CSP) technology is a possible approach to manage renewable resources in Malaysia. Using a techno-economic analysis, the researchers, engineers, industries, or government agencies will be able to identify contributing and discouraging factors of building the CSP technology. This paper presents a techno-economic analysis of two CSP technology: parabolic trough collector (PTC) and solar power tower (SPT), for potential implementation in Malaysia. This paper provides information on two CSP technologies to researchers and industries prior to the planning and design stages. The techno-economic analysis begins with identifying potential locations based on the direct normal irradiation (DNI). Kuah, Kuantan, Miri and Labuan are identified as the potential locations using the RETScreen Expert software. Labuan could be the most promising PTC and SPT technology project because it has the highest DNI received annually. Next, the techno-economic analysis uses two reference projects, ANDASOL-1 and PS-10 systems in Spain, as references for all locations. The techno-economic analysis consists of annual electricity generation, unit cost of electricity, net Present Value (NPV), benefit-to-cost ratio (B/C), internal rate of return (IRR), and payback period calculated in Microsoft Excel. Finally, a sensitivity analysis is conducted to measure the impact of uncertainties of one or more input variables, leading to uncertainties on the output variables. Two sensitive factors are the annual electricity generation and the initial cost, affecting the construction, installation, and implementation of PTC or SPT technology.

On the thermal and thermodynamic analysis of parabolic trough collector technology using industrial-grade MWCNT based nanofluid

The thermal and thermodynamic performance of parabolic trough solar collector (PTC) could be enhanced by using nanofluids due to their enhanced thermophysical properties. In this work, numerical and experimental investigations were carried out to study the effect of suspended industrial-grade multi-walled carbon nanotubes (MWCNTs) in distilled water (DW) for low to medium temperature PTCs. Stable nanofluids were prepared at various volume concentration of 0.05%, 0.1%, and 0.3%. Moreover, a one-dimensional numerical model is developed to investigate the optical and thermo-hydraulic performance of the commercial IST-PTC at different locations in the United Arab Emirates (UAE). The results of simulations show that Abu Dhabi is the best location with the highest annual thermal efficiency of 49.52%. Also, the suspension of MWCNTs nanoparticles in water results in an improvement of Nusselt number by 12%, 16%, and 21% for nanoparticle concentrations of 0.05%, 0.1%, and 0.3%, respectively. The impact of inlet temperature and flow rate are also investigated, and a thermodynamic analysis is carried out to study the entropy generation. The use of nanofluid at low concentrations could enhance the thermo-hydraulic performance for flow rates lower than 0.2 L/s, while nanoparticles concentration should be increased at higher flow rates for better heat transfer. • Stable industrial grade MWCNT/DW nanofluid are prepared and characterized. • Abu Dhabi is the most suitable location in UAE for PTC technology. • Nusselt number is enhanced by up to 21% for 0.3% nanoparticle loading. • Thermo-hydraulic performance enhanced for flow rates below 0.2L/s. • Adding nanoparticle concentrations is needed for higher flow rates.

Analytical assessment of a concentrated solar sub-critical thermal power plant using low temperature heat transfer fluid

The paper presents energy–exergy–economic–environment–ethics analysis of a concentrated solar thermal power plant. Design basis of a concentrated solar power for 24 h operation on parabolic trough collector technology in best suited direct normal irradiation location and least capital cost analysis has been presented. An unconventional approach of reducing the capital cost is analyzed by intentionally designing the power plant for sub-critical conditions using a low-cost mineral oil with permissible operating temperature of 320°C in place of the conventional synthetic solar grade oil of 400°C. Using low pressure and temperature steam in the plant, it has been shown that while there is a reduction of 0.1% in energetic efficiency, there is a gain of 0.28% in the exergetic efficiency of the solar power plant conditions, gross thermal efficiency decreases by 1.18% and the net thermal efficiency decreases by 2.91%. However, the energetic and exergetic utilization factor for heat transfer fluid is increased by 0.84 and 5.58%, respectively. By suitably adjusting the solar field configuration and inlet oil temperature, energy savings to the tune of 45% is possible apart from 2.5 times of cost saving. An attempt has been made to quantifiably assess the ethics of switching to renewable electricity through shared responsibility as a novelty in the study. The payback period for the investment has also been shown to reduce from 20 years to 5 years assuming that the carbon price increases, concentrated solar power cost comes down by 25%, and cost at which electricity can be sold increases to US $0.14 (Rs. 10) per unit.

Thermal selective coatings and its enhancement characteristics for efficient power generation through parabolic trough collector (PTC)

World climate is an area of concern due to the use of fossil fuels that have been the most commonly preferred resource of energy since the industrial revolution and urbanization. The target to maintain the lowest level of carbon emissions and greenhouse gases has created an urge to look for renewable energy resources. Among the renewable energy resources available worldwide, solar energy is considered as one of the feasible and mature technologies in view of large-scale commercial deployment. Solar photovoltaic and solar thermal conversion (STC) techniques have been implemented so far and are still advancing towards cost-effective solutions. Parabolic trough collector (PTC) is one such economical and feasible STC technology as far as high-temperature thermal applications are concerned and are being widely used for power generation. This paper is an attempt to present the current scenario of PTC technology along with its various advancements over the years. Further in this paper, selective coatings, coating techniques and heat collection element (HCE) or receiver are discussed in detail with regard to their advancements. The present work also illustrates the progressive trends in PTC technology, particularly with respect to various heat transfer fluids, HCE inserts, selective coatings and other performance factors along with some futuristic aspects with respect to coatings and receiver inserts in view of high thermal performance.

Performance Analysis of Copper Absorber Tube Parabolic Collector

The solar parabolic trough collector technology is one of the most reliable technologies in the field of solar thermal. This is due to the fact that temperatures as high as 400o C can be achieved using this technology. The energy development from these systems used for hot water production, process steam requirement, power generation and many more. Majorly they have wide applications in cooking. They are also used to generate steam at higher temperatures which is used to run a subsequent engine. In the present Paper, performance analysis of copper absorber tube parabolic collector is done for different parameters of the system such as Reflector sheet material, heat transfer fluid, Period of Sun Incidence at different levels the output responses such as Out Temperature of heat transfer fluid, Discharge, and Thermal Efficiency are recorded for each run. The optimization method S/N ratio analysis is applied for determining the optimal parameters level for better responses and the optimum results are confirmed experimentally

Parametric Trough Solar Collector With Commercial Evacuated Receiver: Performance Comparison at Plant Level

A new anidolic parametric trough solar collector (PmTC) having 8.12 m net width aperture has been recently proposed for a commercial evacuated receiver tube with an absorber diameter of 70 mm. Since the collector was designed ignoring transmission, absorption, and reflection optical losses, calculations of the optical efficiency and the incidence angle modifier (IAM) by means of Monte Carlo spectral raytracing simulations using real slope errors distributions and taking into account Fresnel reflection losses were done. Comparison with an Eurotrough parabolic trough collector (PTC) shows an optical penalization of 5.1% due to the reflectivity and additional soiling of the secondary mirror, to an increase in the end losses and to the Fresnel reflection losses. The National Renewable Energy Laboratory (NREL) system advisor model (SAM) was used to perform annual simulations of two commercial 50 MWe oil power plants without thermal energy storage located in Seville. A PTC solar field consisting of 90 loops, each one having four Eurotrough solar collector assemblies (SCA) with 150 m length was first modeled resulting in a gross production of 386 kWh/(m2 yr). A PmTC solar field with the same module length and similar SCA net aperture area was also simulated. A final configuration of 94 loops and four SCAs with 100 m length per loop yields a gross production of 379 kWh/(m2 yr) showing no improvement compared to the reference PTC plant. The present study allows to advance in the understanding of the potential of the anidolic optic to produce optical geometries able to effectively improve the PTC technology in the short-term projecting results at a commercial plant level.

Study on the integration characteristics of a novel integrated solar combined cycle system

This paper proposes a novel integration system of integrated solar energy combined cycle (ISCC), which uses the compressed air from the gas turbine compressor to heat the water from heat recovery steam generator (HRSG) with three pressure levels and to be the Heat Transfer Fluid (HTF) of solar collectors. For each high pressure integration and intermediate pressure integration, the solar energy is used to heat the water from the high pressure feedwater pump and the intermediate pressure feedwater pump, respectively. Then the water is preheated, evaporated, even superheated. Different ISCC configurations with 30 MW design capacity of solar power are compared, including a solar field based on parabolic trough collectors working with the HTF and the compressed air. The results show that the maximum annual solar power efficiency of the novel system is 13.6%, 1.3% higher than that with the HTF, and the minimum electricity cost is 0.266€/kWh, 0.094€/kWh lower than that with the HTF. Meanwhile, considering the efficiency reductions at the pump and turbine working on the off-design condition, the optimal HTF temperature is obtained for each pressure integration with different design capacities of solar power. This novel ISCC system offers a new utilization way for the parabolic trough collector technology.

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.

Process Heat Generation Potential from Solar Concentration Technologies in Latin America: The Case of Argentina

This paper evaluates the potential of solar concentration technologies—compound parabolic collector (CPC), linear Fresnel collector (LFC) and parabolic trough collector (PTC)—as an alternative to conventional sources of energy for industrial processes in Latin America, where high levels of solar radiation and isolated areas without energy supply exist. The analysis is addressed from energy, economic and environmental perspective. A specific application for Argentina in which fourteen locations are analyzed is considered. Results show that solar concentration technologies can be an economically and environmentally viable alternative. Levelized cost of energy (LCOE) ranges between 2.5 and 16.9 c€/kWh/m2 and greenhouse gas (GHG) emissions avoided range between 33 and 348 kgCO2/(m2·year). CPC technology stands out as the most recommendable technology when the working fluid temperature ranges from 373 K to 423 K. As the working fluid temperature increases the differences between the LCOE values of the CPC and LFC technologies decrease. When 523 K is reached LFC technology is the one which presents the lowest LCOE values for all analyzed sites, while the LCOE values of PTC technology are close to CPC technology values. Results show that solar concentration technologies have reached economic and environmental competitiveness levels under certain scenarios, mainly linked to solar resource available, thermal level requirements and solar technology cost.

Line-focusing concentrating solar collector-based power plants: a review

Concentrated solar power (CSP) plant is an emerging technology among different renewable energy sources. Parabolic trough collector (PTC)-based CSP plant, using synthetic or organic oil as a heat-transfer fluid, is the most advanced technology. About 87 % of the operational capacities of CSP plants worldwide are based on PTC technology. Direct steam-generating linear Fresnel reflector (LFR) systems have been developed as a cost-effective alternative to PTC systems. Line-focusing concentrating solar collectors (PTC and LFR), with single-axis tracking, are simple in design and easy to operate. Prior to the detailed design of a CSP plant, it is necessary to finalize type of the solar field, type of the power-generating cycle, overall plant configuration, sizing of the solar field and the power block, etc. The optimal design of a CSP plant minimizes the levelized cost of energy for a given site. In this paper, a detailed review of important design parameters which affect the design of line-focusing concentrating solar collector-based power plants is presented. This includes parameters for solar collector field design, receiver, heat-transfer fluid, thermal energy storage, power-generating cycle, sizing and configuration of the plant, etc. This review may provide a reference for designing CSP plants. Future research directions are also identified.

Optical Analysis of a Two Stage XX Simultaneous Multiple Surface Concentrator for Parametric Trough Primary and Flat Absorber With Application in Direct Steam Generation Solar Thermal Plants

Today most commercial parabolic trough collector (PTC) solar power plants make use of the well-known LS3/Eurotrough optics. The PTC has a concentration ratio relative to the maximum thermodynamic limit equal to 0.31. In order to improve the competiveness of PTC technology, two well differentiated R&D strategies have been undertaken: (i) developing larger parabolic troughs, which places a higher demand in tracking accuracy and lower tolerances with respect to wind loads, quality of mirrors, control and assembly imprecisions, and (ii) developing secondary concentrators with the aim of bringing the concentration ratio relative to the maximum one as close to 1 as possible. In this paper, a parametric trough collector (PmTC) for a flat receiver designed with the simultaneous multiple surface (SMS) method is proposed. The method assumes zero transmission, absorption, and reflection optical losses and allows for both reflective primary and secondary surfaces (XX-reflective plus reflective) to be simultaneously designed, guaranteeing Etendue matching. The proposed PmTC geometry increases the referred ratio up to 0.59 with a rim angle greater than 100 deg and with the same effective acceptance angle as the PTC. The flat absorber can be replaced with a multitube receiver for application in direct steam generation (DSG).

Benchmark of Concentrating Solar Power Plants: Historical, Current and Future Technical and Economic Development

This paper compares the evolution of Concentrating Solar Power (CSP) Plants. The study is based on a data of 240 CSP plants whose give us a roadmap of technical and economic characteristics of these systems. On the basis of this information collected from the literature, we benchmarked and analyzed the state of the CSP plants from 1982 to 2020. As statistical results show, 87% of CSP projects are located in Spain and USA, but other countries have invested in CSP since 2012. Solar technologies analyzed are Parabolic Trough collector (PTC), Solar Power Tower (SPT), Linear Fresnel Reflector (LFR), and Parabolic Dish Collector (PDC). As detailed data studies for Fresnel and Dish are hardly available, special attention was given to parabolic trough system. The progressive reduction in investment cost of PTC technology over time is presented, taking also into account the energy storage option. Our sensitivity analysis indicates that PTC with thermal oil and molten salt storage at 50 MW is the most mature system, but SPT plants are promising and might have the greatest potential by early 2018.