Concentrated Solar Power Systems Research Articles

Coordinated control strategy for concentrated solar power systems considering active defocusing

With an increasing proportion of renewable energy in the energy structure, concentrated solar power plants are required to respond rapidly to automatic generation control (AGC) commands, to ensure the grid stability when connected to the grid. Active defocusing affects the collecting capacity of the collector, which not only serves as a safety protection measure for system operation, but also improves the system load shedding rate and provides the possibility of system participation in the auxiliary service of grid frequency regulation. In this paper, a coordinated control strategy for parabolic through concentrated solar power (PTCSP) system considering active defocusing of collector is proposed. The coordinated controller utilizes four manipulated variables, including mass flow rate of heat transfer oil in the collector, active defocusing angle, mass flow rate of molten salt in the heat storage system, and main steam valve opening, to regulate three output variables, namely, collector outlet temperature, turbine power, and main steam pressure. By integrating the steady-state defocusing angle in the optimization function, the controller can utilize the extra control freedom degree to improve the control effect, and ensure that the final steady-state defocusing angle to be small, which reduces the unnecessary heat collection loss. The proposed control strategy improves the power response rate and also avoids excessive heat transfer oil temperature and main steam pressure. In the simulations featuring two 20% variations in load target value, the root mean square error of the outlet temperature of the collectors is reduced by 0.094, and the heat storage is reduced by 0.99 MWh.

Agile Deflectometry

Concentrating Solar Power (CSP) systems use mirorrs to focus light onto a receiver, and high optical slope accuracy is required to achieve high concentration. Deflectometry is a technique for measuring optical slope directly, at fine spatial resolution across a miror surface. In this paper we report techniques for making an existing deflectometry system, SOFAST, more flexible and easier to deploy across a wide range of application scenarios. Example applications include mirror prototype development, high-volume manufacturing, outdoor in situ heliostat inspection, and education. We report using the resulting system to measure mirrors ranging in diameter from 0.13 m to 9.3 m, a range of nearly two orders of magnitude. Hardware implementations vary from a simple laptop computer to a system combining a computer, projector, screen, and camera. These efforts pursue a goal of making deflectometry easier to use, applicable to a wider range of problems, and widely available to the CSP community.

A coupled fluid-thermo-mechanical evaluation of various freeze recovery strategies for molten salt parabolic trough collectors

This research advances the field of Concentrating Solar Power (CSP) by offering a comprehensive assessment of freeze-recovery strategies for molten salt parabolic trough collectors, essential for the next generation of CSP plants. Employing a cutting-edge transient 3D Conjugate Heat Transfer (CHT) model, the research elucidates the significant yet previously underestimated role of natural convection in the phase transition of solidified salts. The study demonstrates that the strategic inclusion of impedance heating not only accelerates the defrosting process but also minimizes thermal stresses within the absorber tubes, ensuring mechanical integrity. Moreover, the dual-method approach, which combines solar and impedance heating, reveals a potential to improve the Levelized Cost of Electricity (LCOE) by 4% annually following a complete freeze event. The research conclusively suggests that this synergistic strategy could yield substantial operational cost savings while maintaining the structural robustness of CSP systems. The presented findings provide a detailed blueprint for enhancing plant resilience and economic viability, opening new avenues for operational excellence in CSP technology.

Preface: SolarPACES 2022, 28th International Conference on Concentrating Solar Power and Chemical Energy Systems

The SolarPACES 2022 International Conference was held from September 27 to September 30, 2022 in Albuquerque, New Mexico. As the premier international conference and network for advancing commercial deployment and research and development of concentrating solar-thermal power (CSP) and related technologies, the community was excited to convene in person after two years of virtual collaboration. The conference brought together more than 400 participants from 29 countries. The technical presentations and plenary sessions highlighted exciting advances in state-of-the-art commercial deployment and next-generation research and development. There was much focus on emerging commercial markets, including the value of thermal energy storage for cost-effective long duration energy storage – charged either with electricity or solar heat – and the use of solar thermal energy for industrial and chemical processes, especially to decarbonize the large portion of energy that’s currently used for industrial process heating. By holding the conference in the U.S., we were able to highlight particular technical and strategic objectives being advanced by the U.S. Department of Energy (DOE) and the US Government, including the progress in advancing the Generation 3 (Gen3) CSP test facility [1] at Sandia National Laboratories. This megawatt-scale system will demonstrate a fully integrated thermal transport and storage system that can collect, store, and deliver heat above 700° Celsius, using solid particle heat transfer media. Attendees to the conference were able to tour the globally renowned CSP research center at Sandia National Laboratories and the National Solar Thermal Test Facility (NSTTF). The NSTTF opened in 1978 as the world’s first tower research facility for CSP and has been operating for more than 40 years. The site has been a center of excellence in the development of molten salt technologies for CSP and has played a key role in the demonstration of technologies used in some of the largest solar power plants in the world. We also highlighted the recent announcements from the U.S. Department of Energy of the Energy Earthshot Initiatives to accelerate breakthroughs of abundant, affordable, and reliable clean energy solutions by the end of this decade. Specifically, the Long Duration Storage Shot [2] established a target to reduce the cost of grid-scale energy storage by 90% for systems that deliver 10 or more hours of duration, to $0.05 per kilowatt-hour of electricity delivered from storage. The Industrial Heat Shot [3] aims to develop cost-competitive industrial heat decarbonization technologies with at least 85% lower greenhouse gas emissions by 2035. Hydrogen Shot [4] seeks to reduce the cost of clean hydrogen by 80%, to $1 per 1 kilogram. CSP technologies have promising potential to contribute to all of these important goals. The 2022 conference covered important contributions in all of these areas, and more, across 15 technical tracks, coordinated and chaired by international experts in each field. We had high quality contributions across the board, including 211 oral presentations and 111 posters. Additionally, the plenary sessions brought together leading experts on energy storage, US and global markets for CSP technologies, and a specific focus on industrial decarbonization. On behalf of SolarPACES, I thank all of the conference participants, authors, presenters, track chairs, and the conference organizing committee for an extremely successful meeting! Avi Shultz Chairman of the 28th SolarPACES conference

Prediction of Circumsolar Irradiance and Its Impact on CSP Systems under Clear Skies

In this work, a model to estimate circumsolar normal irradiance (CSNI) for several half-opening angles under clear skies was developed. This approach used a look-up table to determine the model parameters and estimate CSNI for half-opening angles between 0.5° and 5°. To develop and validate the proposed model, data from five locations worldwide were used. It was found that the proposed model performs better at the locations under study than the models available in the literature, with relative mean bias error ranging from −13.94% to 0.70%. The impact of CSNI for these different half-opening angles on concentrating solar power (CSP) systems was also studied. It was found that neglecting CSNI could lead to up to a 7% difference between the direct normal irradiance (DNI) measured by a field pyrheliometer and the DNI that is captured by CSP systems. Additionally, a case study for parabolic trough concentrators was performed as a way to estimate the impact of higher circumsolar ratios (CSR) on the decrease of the intercept factor for these systems. It was also concluded that if parabolic trough designers aim to reduce the impact of CSNI variation on the intercept factor, then parabolic troughs with higher rim angles are preferred.

A cascaded thermochemical energy storage system enabling performance enhancement of concentrated solar power plants

Calcium looping (CaL) thermochemical energy storage (TCES) exhibits promising potential for application in concentrated solar power (CSP) plants. However, the CSP-CaL integrating system encounters challenges related to elevated heat loss and diminished power generation efficiency. Herein, for the sake of a more rational heat management and enhanced energy utilization, we propose a cascaded energy storage and utilization strategy. Accordingly, a cascaded TCES system model consisting of Calcium looping and Magnesium looping (MgL)-MgCO3/MgO thermochemical cycle subsystem is developed. The energy analysis and exergy analysis results show that the solar power efficiency and exergy efficiency of the considered system are 41.7% of 44.7%, which are 2.6% and 2.8% higher than the single CaL energy storage CSP system, respectively, demonstrating the superiority of the proposed strategy and system for CSP application. Furthermore, the operation strategy of the system under off-design conditions is proposed by considering the real solar irradiation, and the yearly overall solar power efficiency is 39.2%. The economic analysis of the proposed system indicates that the levelized cost of electricity ranges from 179–156 $/MWh for different plant sizes and is superior in large-scale CSP plants. The cascaded energy storage and utilization strategy of thermochemical cycles with different working temperatures provides better dispatchability to meet the different thermal energy demands.

Experimental Investigation of a Small-Scale Parabolic Trough Concentrated Solar Power ‎Systems

Large-scale systems have a lower levelized cost of electricity than small-scale concentrated solar power systems. Thus, the purpose of the present study is to evaluate the potential of using standalone small-‎scale ‎concentrated ‎solar power collectors in order to generate process ‎heat ‎at ‎a ‎moderate ‎temperature, which directly utilizes thermal energy without the need to generate electricity. ‎A ‎parabolic trough ‎collector (3.6m2) ‎was ‎designed ‎and ‎manufactured, including a dual-axis solar tracking system with and without an insulating function. An ‎insulating ‎cavity ‎was incorporated to ‎minimize the heat ‎losses collected by the absorbed ‎tube. ‎The experiments ‎were ‎carried out during a time of high winds and unfavorable weather ‎in ‎Sabratha City. The findings of the experiments demonstrated that the produced temperature and the collected heat energy progressively increase until they reach their maximum value, and then gradually decrease. The maximum water ‎temperature ‎was 96ºC at ‎a ‎flow rate ‎of ‎‎0.5L/min, and ‎the highest amount of ‎heat energy was 550W/m². ‎Wind speed showed an important impact on the produced temperature; therefore, various comparative experiments were carried out in the same climate condition; ‎the experiment with the insulating function ‎presented the least heat loss, and it takes a higher edge of 11% in terms of efficiency. ‎In addition, the water temperature rose to 120°C where steam was generated at a zero flow rate, while the oil ‎reached 194ºC. In addition, a mathematical model was also implemented to theoretically study energy balance; with little expected discrepancy, its predictions and the experimental results agreed. In conclusion, the results presented reasonable markers of interest despite the poor environmental conditions during the experiments.‎

Analysis of the Performance of a Hybrid Thermal Power Plant Using Adaptive Neuro-Fuzzy Inference System (ANFIS)-Based Approaches

The hybridization of conventional thermal power plants by the incorporation of renewable energy systems has witnessed widespread adoption in recent years. This trend aims not only to mitigate carbon emissions but also to enhance the overall efficiency and performance of these power generation facilities. However, calculating the performance of such intricate systems using fundamental thermodynamic equations proves to be both laborious and time-intensive. Nevertheless, possessing accurate and real-time insights into their performance is of utmost significance to ensure optimal plant operation, facilitate decision making, and streamline power production planning. This paper explores the novel application of machine learning techniques to predict the performance of hybrid thermal power plants, specifically the integrated solar combined cycle power plant (ISCCPP). These plants combine conventional thermal power generation with renewable energy sources, making them crucial in the context of carbon reduction and enhanced efficiency. We employ three machine learning approaches: the adaptive neuro-fuzzy inference system (ANFIS), ANFIS optimized via particle swarm optimization (ANFIS-PSO), and ANFIS optimized through a genetic algorithm (ANFIS-GA). These methods are applied to the complex ISCCPP, comprising steam and gas turbine sections and a concentrated solar power system. The results highlight the accuracy of ANFIS-based models in evaluating and predicting plant performance, with an exceptional overall correlation coefficient of 0.9991. Importantly, integrating evolutionary algorithms (PSO and GA) into ANFIS significantly enhances performance, yielding correlation coefficients of 0.9994 for ANFIS-PSO and 0.9997 for ANFIS-GA, with ANFIS-GA outperforming the others. This research provides a robust tool for designers, energy managers, and decision makers, offering valuable support in assessing the performance of hybrid thermal power plants. As the world transitions to cleaner energy sources, the insights gained here are poised to have a significant impact on the growing number of these thermal power plants globally.

Binary nitrate molten salt magnetic microcapsules modified with Fe3O4-functionalized carbon nanotubes for accelerating thermal energy storage

Molten salts are important media for heat transfer and thermal energy storage in concentrated solar power (CSP) system, but it has drawbacks such as poor thermal conductivity and corrosive properties. This study increases the thermal energy utilization rate and expand the range of applications for phase change materials by developing a multifunctional magnetic microcapsule phase change material composed of SiO2@Solar Salt microcapsule and Fe3O4-functionalized carbon nanotubes (CNTs-Fe3O4). The microcapsules have regular spherical core-shell structure and relatively small size, which improves the disadvantage of corrosiveness of molten salt and prolongs their working life. The microcapsule not only shows a good latent heat-storage capability with satisfactory phase-change enthalpies of over 88.6 J/g under an encapsulation efficiency of over 61.6 %, but also exhibits high temperature stability and cycling stability. The encapsulation of SiO2 and introduction of the CNTs-Fe3O4 high thermal conductivity enhancement phase increased the thermal conductivity of the microcapsules by approximately 53.4 % compared with pure nitrate. The microcapsules also possess superparamagnetic characteristics and photothermal conversion characteristics, both of which may be used as an additional method to improve the thermal storage efficiency. As a result, this novel material provides a promising solution for energy collecting, conversion, and storage.

Experimental evaluation for enhancement of small-scale concentrated solar power ‎systems – a case study ‎for solar cooking

ABSTRACT Small-scale concentrated solar power systems have a higher levelized cost of electricity than large-scale systems. Therefore, this ‎study aims to evaluate small-scale concentrated solar ‎power ‎systems, ‎which use thermal energy ‎directly without having to produce ‎electricity, with particular emphasis on the use of solar ‎cooking. ‎ The sun’s rays are reflected using a huge number of mirrors and focused on a ‎focal ‎point (the target), in this study, the bottom of the ‎cooking pot.‎ ‎The study encompasses three ‎main ‎parts: 1) the design and manufacture of a small-scale central receivers model for solar cooking; 2) the installation of an automated solar tracking system; and 3) the ‎experimental studies. The area of the proposed model is 1 ‎m2, while the ‎heliostat ‎area is 0.56 ‎m2. For the tracking procedure, the astronomical almanac method was utilized to estimate the sun’s position; this technique is not affected by ‎ambient ‎conditions like ‎clouds.‎ Despite employing normal flat mirrors and conducting the tests in inclement weather (winter), the results were excellent and suggested a possible interest. A half-liter of water took 20 minutes to heat up to the point of starting boil, and 193°C was the oil’s highest measured temperature‎. This result can be improved by using high-absorptivity cooking pots and specialized mirrors such as Fresnel lenses. Efficiency for the water studies varied from 50% to 76%, where a half litter took only 18 minutes to get to the highest temperature, while for a half litter of oil, efficiency was 79%.

Small-scale concentrated solar power system with thermal energy storage: System-level modelling and techno-economic optimisation

A dynamic, techno-economic model of a small-scale, 31.5 kWe concentrated solar power (CSP) plant with a dish collector, two-tank molten salt storage, and a sCO2 power block is analysed in this study. Plant solar multiple and storage hours are optimised using a multi-objective genetic algorithm to minimise the levelised cost of electricity (LCOE) and maximise the capacity factor (CF). The optimal LCOE is found to be ranging from 122.7 USD/MWhe to 217.8 USD/MWhe when using optimistic and pessimistic power block cost assumptions. In contrast, the literature reports an LCOE of 193.9 USD/MWhe for a similar 31.5 kWe CSP system without storage. The addition of thermal energy storage in the system configuration dramatically improves the CF from 30.4%—reported in the literature—to 87.2% obtained from the present model. The sensitivity analysis suggests that upscaling the system to 400 kWe reduces the LCOE to 121.9–172.2 USD/MWhe as a result of lower unit power block costs at larger scales. The comparison of CSP and PV-battery systems in three distinct locations—characterised by varying direct and global solar resources—indicates that the CSP system is promising in locations with abundant direct normal irradiance (DNI). For locations with medium DNI resource, the LCOE of PV-battery system is within the margin of uncertainty of CSP system. In low-DNI locations, PV-battery systems proved to be preferable.

Enhanced high-temperature thermal stability of the novel MoAlSiN-based solar selective absorbing coatings by optimizing the multilayer structure

Solar selective absorbing coating (SSAC) plays an important role in the high-temperature concentrated solar power system. The high thermal stability of SSAC above 600 °C has been a big open question for molten salt concentrated solar power projects. In our work, the TiN/Mo/MoAlSiN/MoAlSiON/SiO2 and the TiN/Mo/MoAlSiN/Si3N4/SiO2 SSACs are developed for getting high-temperature thermal stability, besides excellent spectral selectivity. The solar spectral absorptivities of the MoAlSiN/MoAlSiON and MoAlSiN/Si3N4 SSACs are 95.2% and 93.2%, respectively. While the infrared emissivities of the MoAlSiN/MoAlSiON and MoAlSiN/Si3N4 SSACs are controlled below 10.6% and 10.5% at 400 °C, respectively. The novel MoAlSiN/Si3N4 SSAC deposited on quartz can maintain thermal stability even after heat treatment at 800 °C for 200 h in vacuum, which is one of the best results in the research field for high-temperature SSACs. It is found that the choice of suitable materials without oxygen and the elimination of interfacial thermal stress are very important for improving thermal stability. Furthermore, the practical total energy conversion efficiencies of the MoAlSiN/Si3N4 SSAC at 600 °C–800 °C are always above 57%. When the activation energy is assumed as 180 kJ/mol, the estimated service life of the MoAlSiN/Si3N4 SSAC at 600 °C is more than 25 years.

Techno-economic assessment of a numbering-up approach for a 100 MWe third generation sodium-salt CSP system

This work presents the design and techno-economic analysis of a 100 MWe concentrated solar power (CSP) system using a supercritical CO2 power block with 700 °C input temperature. Aiming to leverage the relatively higher efficiency of small heliostat fields and potential multi-build discounts, a numbering-up approach is examined, developing four alternative configurations (1×100, 2×50, 3×33, and 4×25MW˙e), in which each module has its own dedicated tower, heliostat field, receiver, thermal storage and power block. A comprehensive techno-economic model is combined with detailed annual simulations to yield levelised cost of energy (LCOE) estimations and analyse the potential of system numbering-up for high-temperature next-generation CSP systems based on liquid heat transfer fluids (HTFs). The simulations are verified against the System Advisor Model with differences in the LCOE calculations within ±1.0%. Comparing the four systems shows that a 1×100MW˙e system leads to an LCOE of 54.88USD/MWh˙e, lower than for the numbered-up modules. However, the LCOE difference between configurations with one and two modules is moderate, with the 2×50MW˙e configuration showing an LCOE of 55.99USD/MWh˙e (+2%). Despite their higher annual conversion efficiencies, the 3×33MW˙e and 4×25MW˙e systems are more capital-intensive and escalate LCOE by 6.9 and 12.2%, respectively. With size-dependent power block efficiency, further LCOE escalation with numbered-up systems is observed, however, multi-build savings could potentially reverse this cost escalation and a 13.9–19.6% saving on the two-module system would allow them to break even.

Strength analysis of molten salt tanks for concentrating solar power plants

Promoting the development of concentrating solar power (CSP) is critical to achieve carbon peaking and carbon neutrality. Molten salt tanks are important thermal energy storage components in CSP systems. In this study, the cold and hot tanks of a 100 MW CSP plant in China were used as modeling prototypes. The materials and geometric models were determined based on related specifications and engineering experience. Mechanical characteristics of the tanks under steady condition, including the deformation, stress distribution, and stress concentration, were simulated and calculated. Furthermore, the strength of the tank walls was evaluated. The findings can be used as a reference for designing the molten salt storage tank and reducing the risk during the operation.

Temporal performance indicators for an integrated pilot-scale membrane distillation-concentrated solar power/photovoltaic system

Management of concentrate streams in inland applications has uncertain long-term environmental impacts. This study investigates an intensified solar-energy capture desalination system that integrates membrane distillation (MD) with a hybrid concentrated solar power (CSP)/photovoltaic (PV) collector to realize self-sustained zero-waste discharge for effective management of concentrate streams in inland and off-grid applications. The demonstration-scale CSP/PV system can produce up to 178 kWh of thermal energy and 4 kWh of electrical energy per day. The thermal and electrical energy from the CSP/PV system is directly supplied to the air gap MD (AGMD) pilot-scale system producing up to 288 L of distilled water per day. Experiments were performed on the hybrid AGMD-CSP/PV system to evaluate system performance under various operating conditions including AGMD and CSP flow rates, CSP system pre-heating, and AGMD vacuum pressure. Experimental results indicate that doubling the AGMD flow rate results in a 119% increase in thermal energy utilization and a 71% increase in distillate production. Compared to the winter months, operating the system in summer months when direct normal irradiance (DNI) is highest results in nearly double the distillate production (88 L in winter and 168 L in summer) and nearly three times the amount of thermal energy consumption (15 kWh in winter and 43 kWh in summer). Operating with vacuum resulted in a 34% increase in distillate production and allowing the thermal storage reservoir to preheat in the winter resulted in a 61% increase in distillate production. Overall, experimental results highlight the tradeoff between distillate production and thermal and electrical energy production and consumption under various environmental conditions and the potential for AGMD-CSP/PV to be a stand-alone desalination system.

Geographical information systems based site selection methodology for renewable energy systems in Palestinian territories

<span lang="EN-US">Renewable energy is the key term for the energy industry sector in the world recently. Palestinian territories (PT) have good potential for multiple renewable energy applications. The purpose of this study was to evaluate the potential sites for solar photovoltaic systems, concentrated solar power systems, and wind farms in the West Bank (WB). The study was derived from geographical information systems (GIS) and multi-criteria decision making (MCDM). The criteria for each application were identified and weighted according to the analytical hierarchy process (AHP). All the resulting layers were multiplied to produce the final suitability map for each application. The results of the study depend on two scenarios, In the first scenario, where area C is included, the areas classified as highly suitable for photovoltaic (PV), concentrated solar power (CSP), and wind turbines are between 14.27 and 7.56 km<sup>2</sup>. The second scenario is excluding area C, the highly suitable areas were between 4.1 to 2.47km<sup>2</sup>.</span>

Evaluation of the calcium chloride-calcium fluoride system for high temperature thermal energy storage

The storage of excess or unutilised energy generated by renewables remains a key unsolved piece in the decarbonisation of the energy sector. One potential way to solve this is through the use of thermal energy storage which can use the heat as is (e.g., in concentrated solar power systems) or through the conversion of electricity to heat (e.g., through resistive heating) at very low costs. To achieve these low costs, high storage densities and low-cost materials should be utilised. A potential way to achieve this is by harnessing the energy released during phase change in appropriate materials such as molten salts. Therefore, the current study investigates calcium chloride and mixtures of calcium chloride and calcium fluoride as storage options. Aside from the pure salt, a eutectic was found at 647 ± 1.7 °C and 18.3 mol% calcium fluoride, while a peritectic was also found at 730 ± 2.3 °C and 41 mol% calcium fluoride. Determination of the storage density of the materials was undertaken using differential thermal analysis and differential scanning calorimetry to measure the enthalpy of transition and specific heat capacity. These results showed high heats of transition (298–310 ± 15.0 J/g) and heat capacities (0.72–1.02 ± 0.1 J/g∙K) making them potentially a cost-effective high temperature storage medium.

Modeling of a hybrid power system integrating solar radiation and syngas combustion energy

AbstractThis study aims to model a hybrid power system that can continuously generate power by switching between two possible thermal sources: solar radiation and combustion energy from synthesis gases. The system comprised a hybrid energy receiver, solar dish, Stirling generator, fluidized‐bed gasifier, boiler, and water tank. The solar dish was a dual‐reflection solar collector that used two mirrors, namely the main and subordinate concentrators, to concentrate a broad expanse of solar radiation onto a hybrid energy receiver. The fluidized‐bed gasifier was employed for the production of synthesis gases. The synthesis gases were combusted to provide an auxiliary heat source for the Stirling generator when solar radiation was insufficient. Solar radiation or combustion energy was alternatively introduced into the hybrid energy receiver and converted to power by a 1‐kW‐scale beta‐type Stirling engine. In this manner, the Stirling generator could serve as a base‐load power plant regardless of solar conditions. In this study, a complete quantitative model was developed for a demonstration plant by incorporating thermodynamic and dynamic models of the beta‐type Stirling engine, a ray‐tracing model for the dual‐reflection solar dish, an energy model of the hybrid energy receiver, and experimental data for the fluidized‐bed gasifier. The performance response of the system during switching between solar radiation and combustion energy was predicted. The modeling results indicated that switching can result in a continuous power output ranging from 600 to 1200 W. With synthesis gas combustion as the auxiliary heat source, the hybrid Stirling power system can be operated continuously, and the overall power output is increased by 109.82% compared to a conventional concentrated solar power system that only uses solar radiation.

Techno-economic optimization of molten salt based CSP plants through integration of supercritical CO2 cycles and hybridization with PV and electric heaters

The present study explores the integration of supercritical CO2 (sCO2) power cycles into Concentrating Solar Power (CSP) plants using molten salt, and the hybridization of these plants with solar photovoltaic (PV) systems through electric heaters. Techno-economic evaluations determined the optimal power cycle configuration and subsystem designs for two different scales and locations and then compared them with state-of-the-art solar power plants. The results show that hybridizing PV with state-of-the-art CSP can lead up to a 22% reduction in the Levelized Cost of Electricity (LCOE) compared to standalone CSP systems. This hybridization and the use of electric heaters are particularly beneficial for small-scale installations and locations with low DNI/GHI ratios. By replacing the steam Rankine cycle with a sCO2 power block, a further 42% reduction in LCOE can be achieved at small scales, even with a simple recuperated cycle. In conclusion, the hybridization with PV and the integration of sCO2 power blocks provide cost benefits despite the temperature limitations imposed by the molten salt. Hybrid PV-CSP plants with sCO2 power blocks prove to be a cost-effective solution for capacity factors exceeding 60%. For lower capacity factors, configurations combining PV with battery energy storage or PV with electric heaters, thermal energy storage, and sCO2 power blocks are preferable options.

Pengembangan Alat Desalinasi Air Laut dengan Teknologi Thermal Energy Storage

The need for clean water in household life is very important because humans cannot live without it. The composition of seawater consists of 96.5% pure water and 3.5% other materials, namely salts, dissolved gases, and others. Indonesia is one of the countries that has the second-longest coastline in the world, so the potential for utilizing sea water is very large, one of which can be through the desalination process. Distillation itself is distillation, and its by-product is salt when seawater is heated using a heat energy source with a concentrated solar power (CSP) system. Based on research that has been done previously, the tool is a lab-scale seawater desalination device, but the process of making a lab-scale seawater desalination tool is not optimal. Then design the construction of a lab-scale seawater desalination device with the Multi Stage Flash (MSF) type, and the aim is to determine the performance and functionality of the MSF-type lab-scale seawater desalination device. The results show that the results of the coil heat exchanger development obtained an inlet temperature of 85.9°C and an outlet temperature of 67.8°C, and the room temperature in the chamber can be maintained at a temperature of 68.9°C. As for the components being developed, such as sea water pumps, hoses, tees, and sprayers, a sea water debit of 53.78 liters per hour has been obtained.