Concentrated Solar Power Research Articles

The low-carbon economic scheduling method for regional integrated energy systems considering the joint integration of electric vehicles and concentrated solar power plants for wind power consumption

In northern China, there is a serious problem of source-load imbalance and significant wind curtailment, mainly due to the limitations of the “heat determines electricity” mode of operation of combined heat and power (CHP) units in winter. To further absorb excess wind power and overcome these limitations, this paper proposes an optimized scheduling method for a regional integrated energy system (RIES) based on source-load coordination. Firstly, on the supply side, the paper introduces the concept of a concentrated solar power (CSP) plant and an electric boiler for combined heat and power generation to provide heating, partially decoupling their operation mode from “heat determines electricity.” Secondly, on the demand side, the impact of electric vehicles (EV) is considered. A formula for the fluctuation ratio of peak-to-off-peak electricity prices is established, and EV charging and discharging are guided by electricity prices to fully exploit the demand response capability of dispatchable resources on the demand side. Charging loads during peak electricity consumption periods are effectively shifted to off-peak periods, aiding in peak shaving and valley filling. Finally, a tiered carbon trading mechanism is introduced. With the goal of minimizing the total cost of the RIES, an optimization scheduling model for the RIES is established, and the CPLEX solver is used for solving. Simulation results show that under source-load coordination scheduling, the overall efficiency of the system is significantly improved. It can further overcome the limitations of CHP units, enhance wind power consumption capacity, reduce carbon emissions, and improve the economic benefits of the RIES.

Modeling and dynamic characteristics analysis of concentrating-receiver-heat exchanger system of sCO2 solar thermal power plant

In a supercritical carbon dioxide (sCO2) solar thermal power plant system using solid particle as the heat absorption and transfer medium, the concentrating-receiver-heat exchange coupled system composed of a heliostat field, solar particle receiver, and particle/sCO2 heat exchanger is one of the most important subsystems in the power plant system, and its dynamic characteristics directly affect the performance of the whole system. In this paper, taking the 200kWe sCO2 solar thermal power plant as the research objective, firstly, a discretized lumped parameter model of the coupled system was established to study the dynamic performance and operational characteristics based on the TRNSYS platform, and the following characteristics of some key parameters such as particle and sCO2 outlet temperature to the DNI variation were deeply studied without taking any control measures. The results indicate that the particle and sCO2 outlet temperature are positively correlated with the DNI variation and are highly sensitive, and the efficiency of the particle receiver is basically maintained at around 0.7 whether it is sunny or cloudy; Secondly, in order to achieve the rated outlet design parameters, the dynamic characteristics on June 13 and 15, 2023 with a PID control strategy were also studied. The results show that the particle outlet temperature can be maintained at 800 °C by controlling the particle inlet mass flowrate in the particle receiver, while the sCO2 outlet temperature can be guaranteed at 550 °C by adjusting the sCO2 inlet mass flowrate in the heat exchanger with the condition of mild DNI variation. Besides, it is also found that, the PID control is unlikely to be effective under severe DNI changes. Therefore, the addition of buffer particle tanks is essential to compensate for the intermittency of the DNI in the system design process.

Design, off-design and operation study of concentrating solar power system with calcium-looping thermochemical energy storage and photovoltaic-driven compressed CO2 energy storage

The combination of thermochemical energy storage (TCES) based on calcium-looping (CaL) and concentrating solar power (CSP) is favorable as the potential choice for large-scale, low-cost green power production in the future. However, the self-consumption power of TCES based on CaL accounts for a relatively large proportion compared to the existing molten salt energy storage. To this end, this paper innovatively proposes a 50 MW CSP system integrated with CaL-TCES and photovoltaic (PV)-driven compressed CO2 energy storage (CCES). The percentage of system self-consumption has been significantly reduced after system being optimized based on the results of energy and energy analysis. Consequently, the overall system performance is significantly improved with the energy and exergy efficiencies increased from 14.6 % and 15.7 % to 29.4 % and 31.6 %, respectively, at design-point. Furthermore, a parametric study of the optimized system is investigated. Moreover, the annual operational performance of the optimized CSP-CaL system located in Delingha, China is predicted on an hourly basis. Finally, from a techno-economic perspective, the solar multiple (SM) and TCES capacity are optimized aiming the minimal levelized cost of electricity (LCOE). The results indicate that LCOE ranges from 0.010 to 0.159 $∙kWh-1 for different plant sizes and TCES capacities.

Performance assessment of hybrid adsorption/humidification-dehumidification desalination cycle powered by dish/stirling concentrated solar power system for sustainable freshwater production maximization

To achieve sustainable development, it is crucial to prioritize green polygeneration systems capable of generating diverse energy outputs, including electricity, heat, and distilled water, with enhanced efficiencies, reduced costs, and environmentally friendly advantages. Therefore, this study explores an innovative integration for a solar-powered desalination system to present an eco-friendly desalination system that agrees with sustainability goals of eco-friendly clean water and net-zero energy. The proposed system utilizes the waste heat from the solar dish Stirling power engine to drive the adsorption desalination system that is combined with two ejectors, humidification-dehumidification desalination. The humidification-dehumidification utilizes the waste energy from the silica gel-based adsorption desalination system process to enhance the freshwater productivity of the designed integrated system. Comprehensive modeling for the hybrid system components has been formulated using MATLAB to assess the electrical performance and freshwater production of the proposed system. The study also expresses the effect of evaporative-condenser heat recovery in enhancing the freshwater productivity of the hybrid system. Moreover, the effects of cycle time, and evaporator pressure on the performances of the system with and without heat recovery. The findings indicate that the proposed system has the capability to generate an electrical power output of approximately 23.42 kW, achieving a solar-to-electricity efficiency of 23.40 %. Moreover, the proposed system also produces a water production of 47.42 L/hr with a gained output ratio of 2.74. At the same time, the cost estimate revealed that the price of generated freshwater by the planned desalination facility utilizing the heat recovery loop was approximately 0.54 $/m3.

A DFT-based kinetic equation for Co3O4 decomposition reaction in high-temperature thermochemical energy storage

Thermal energy storage supports stable grid integration of variable renewable energy sources by reducing power curtailment and generation costs. Thermochemical energy storage (TCES) offers high energy density and long-duration, long-distance storage advantages, making it a focus in large-scale applications such as concentrated solar power plants. Metal oxide systems like Co3O4/CoO are widely used due to their operational flexibility, yet limited understanding of their decomposition kinetics hinders optimization of TCES materials and reactor design. In this study, we developed a rate equation based on density functional theory and transition state theory to identify the reaction mechanisms and rate constants at the gas–solid interface, prior to predict Co3O4 decomposition kinetics. A microkinetic model was then constructed to couple surface reactions with oxygen ion diffusion across the bulk, which was integrated into a reactor model accounting for mass transfer steps. The model’s accuracy was validated against the data from the micro-fluidized bed thermogravimetric analyzer experiments. For particles smaller than 150 μm, the formation step of adsorbed O2 (energy barrier of 0.8 eV) controls the reaction rate, while gas diffusion dominates the reaction rate for particles larger than 500 μm. To conclude, the optimal conditions for maximizing charge–discharge kinetics in TCES applications were identified as: 850–900 °C, 0–10 vol% O2, and 150–500 μm. This model provides theoretical guidance for optimizing TCES materials and reactor design, reducing experimental costs while maintaining accuracy.

Unique thermal architecture integrating heliostat solar fields with a dual-loop power generation cycle employing thermoelectric; thermal/financial study and GA optimization

This study delineates the development of a solar energy system that leverages concentrated solar power (CSP) technology to supply both electricity and potable water for residential applications. The proposed thermal architecture uniquely integrates heliostat solar fields with a dual-loop power generation cycle, augmented by a seawater desalination system that employs reverse osmosis (RO) membranes. To bolster electricity production, a thermoelectric generator (TEG) has been incorporated into the system's design framework. A comprehensive analysis of the system has been performed, encompassing thermodynamic and economic evaluations. Furthermore, a parametric analysis has been executed to investigate the effects of critical parameters on the system's operational efficiency. The efficacy of the system was rigorously assessed through a case study that examined its capabilities for daily production outputs. This research, grounded in the analytical projections from Saudi Arabia and the favorable environmental conditions characteristic of the region, explores the operational performance of the system within this specific geographical context. The primary objective of this inquiry is to determine the ideal operational parameters by employing multi-criteria optimization methods tailored to the established system. Variations in compressor pressure ratios were found to significantly affect the performance of the Brayton cycle and the exergetic efficiency of the system, with optimal economic efficiency being realized at a specific pressure ratio. Furthermore, increasing the inlet temperatures in the organic Rankine cycle has been shown to improve system efficiency up to a certain limit, beyond which potential reliability issues could arise. The case study demonstrated that electricity generation peaks during the summer months, particularly in June, aligning with a high volume of freshwater production totaling 264,530 m³. The optimization efforts achieved an exergetic efficiency of 17.69 % and an overall cost of $359.58 per hour.

New database of sustainable solid particle materials to perform a material-based design for a thermal energy storage in concentrating solar power

Renewable energies have surged worldwide, aiming to mitigate greenhouse gas emissions and reduce dependence on fossil fuels. Concentrated solar power (CSP) with thermal energy storage (TES) emerges as a viable alternative to bridge the gap between renewable energy generation and consumption. However, existing CSP plants face a significant challenge in optimizing performance due to the operational temperature limitations of solar salt. While alternative materials, such as solid particles for sensible heat storage in solar towers exceeding 600 °C, have been proposed, the crucial aspect revolves around selecting a new alternative sustainable low-cost material for use as a TES media. This article investigates the optimization of CSP-TES systems by evaluating alternative sustainable low-cost materials sourced from several sectors such as the mining or metallurgical industry, municipal solid wastes, or demolition wastes. The materials, either used in their original form or formulated into aggregates for mortars, underwent thorough a property comparison focused on thermal, physical properties, and cost. With this data, a database was created using the Constructor software from ANSYS and integrated with the Selector software from the same company that provides instrumental for the creation of a comprehensive repository of sustainable materials, providing a database that serves as a practical reference guide for optimizing the selection of sustainable materials as TES in CSP plants. Then, a baseline could be established for selecting a sustainable material for a specific design, considering the properties of the materials. This methodology consists of redesigning and adapting the system according to the material, and it is known as the Materials-Based Design (MBD) process.

Low carbon economic scheduling of integrated energy system with concentrating solar power and multi-stage hydrogen utilization based on ladder-type carbon trading

ABSTRACT As the energy crisis and the greenhouse effect intensify, developing a sustainable and clean energy system is particularly important. How to increase the utilization of clean energy and reduce carbon emissions is a pressing issue. To this end, an integrated energy system (IES) framework incorporating multi-stage hydrogen utilization and concentrated solar power (CSP) has been developed. This study optimizes the scheduling of the IES using a ladder-type carbon trading method to optimize the output of each unit, thereby achieving low-carbon economic operation. The research investigates the conversion and utilization among multiple heterogeneous energy flows, including electricity, heat, gas, and hydrogen, with a focus on the integration of multi-stage hydrogen utilization and CSP heat supply, and the interconnections among different units. Four comparative cases are established to evaluate the proposed IES framework in reducing the totalcost, mitigating renewable energy curtailment, and lowering carbon emissions. The results show that the proposed IES framework presents optimal results, with a total cost reduction of 19.74% and a carbon emission reduction of 36.79 tons, no new energy waste, and high carbon benefits. The proposed IES framework facilitates flexible and efficient distribution of multiple energy types, meeting energy demands while enabling multi-energy complementarity and feasibility.

AN ASSESSMENT OF PHASE CHANGE MATERIAL, PREPARATION TECHNIQUES AND CONTAINMENT MATERIAL WITH DIFFERENT MOLTEN SALTS FOR THERMAL ENERGY STORAGE SYSTEM

Molten salts are extensively used as high-temperature heat transfer media and thermal energy storage (TES) materials in concentrating solar power (CSP) plants. Molten salt corrosion is a critical factor influencing the safe operation of the system. This work comparatively summarizes various factors influencing molten salt corrosion, including temperature, impurities, alloy composition and gas atmosphere. Additionally, the corrosion mechanisms of nitrate, carbonate, chloride, and fluoride-based mixture salts are meticulously reviewed. The demand for high-temperature storage is indeed increasing, driven by the need for more efficient and sustainable energy solutions. High-temperature storage systems, particularly those utilizing phase change materials (PCMs) and molten salts, play a key role in enhancing energy efficiency and reducing carbon footprint. By improving the efficiency of energy storage and reducing the need for fossil fuels, high-temperature storage systems help decrease greenhouse gas emissions, contributing to the fight against global warming. The paper focused on enhancing the corrosion resistance of container materials in terms of improving PCM thermal conductivity and stability.

Parametric modeling of green hydrogen production in solar PV-CSP hybrid plants: A techno-economic evaluation approach

This study conducts a unique parametric study to comprehensively assess the integration of Photovoltaics (PV) and Concentrated Solar Power (CSP) for sustained electrolyzer load. An optimal design of the hybrid system is performed, and an economic model for hydrogen production is developed that considers six key parameters: Levelized Cost of Energy (LCOE) of PV, LCOE of CSP, electrolyzer cost, electrolyzer efficiency, electrolyzer stack lifetime hours, and the interest rate. A detailed parametric study for the electrolyzer model involved a dataset of 246,961 unique parameter combinations. The results reveal that the LCOE of CSP and electrolyzer costs are the most influential factors, with proportions of 51.6 % and 21.4 %, respectively. The LCOE's potential 24 % reduction in the Levelized Cost of Hydrogen (LCOH) is the major contributor to the 50 % decrease in CSP costs.”. The study highlights a consistent gradient in LCOH reduction as the electrolyzer cost with the LCOE of CSP decreases. This trend could lead to a remarkable decrease in LCOH to 1.5 $/kg at certain conditions, underscoring the significance of optimizing CSP costs and electrolyzer efficiency for efficient green hydrogen production.

Thermodynamic analysis of a novel concentrated solar power plant with integrated thermal energy storage

This research provides a detailed thermodynamic analysis of a new Concentrated Solar Power (CSP) plant with integrated Thermal Energy Storage (TES). The plant combines a central receiver tower with a supercritical CO2 (sCO2) Brayton power cycle and a hybrid sensible-latent heat storage system.The analysis shows significant improvements in energy and exergy efficiencies (41.3 % and 38.7 %, respectively) compared with conventional CSP plants. The integrated system’s optimal operating conditions are obtained with a receiver temperature of 750 °C, a TES capacity of 12 h, a solar multiple of 2.5, an s CO2 cycle with a turbine inlet temperature of 750 °C, and a pressure ratio of 2.8.The analysis of the TES performance shows the great potential of the hybrid storage system in improving dispatchability and capacity factors. The economic analysis shows acompetitive Levelized Cost of Electricity (LCOE), and the environmental impact assessment shows a great reduction in greenhouse gas emissions.The present study presents a blueprint for developing high-performance CSP systems with advanced components and operating conditions. It demonstrates the promising potential of the proposed CSP-TES system, a viable, efficient, sustainable, and cost-effective technology for power generation. This technology will enable us to address the global transition towards clean energy.

Thermochemical reaction kinetics of Mn-Fe based particles for High-Temperature energy storage systems

Concentrated Solar Power (CSP) systems, augmented by Thermal Energy Storage (TES), are crucial for enhancing renewable energy stability. However, challenges in CSP technology, particularly efficiency and cost factors, persist. Elevating heat collection and storage temperature stands out as an effective strategy to improve efficiency and reduce costs. In this study, we investigated the use of Mn-Fe particles for thermal energy storage in CSP, highlighting their excellent cycling stability and suitability for high temperatures (>900 °C). We conducted a detailed analysis of the oxidation kinetics. The oxygen partial pressure at equilibrium of oxidation process (pO2,eql(Tox))​ was determined and the onset temperature was found to exceed 850 °C, with a noticeable lag at lower pO2, diminishing or disappearing at higher pO2. To sustain a high re-oxidation conversion during the oxidation process, it is crucial to maintain either a high pO2 (>0.16 bar) or a low cooling rate β. The kinetic parameters were subjected to polynomial fitting with pO2 and β as independent variables, followed by an investigation into the correlation between these parameters and the fundamental physical processes of the reaction. Subsequently, a definitive kinetic model for the oxidation of Mn-Fe particle was established, exhibiting a strong correlation with experimental results (R2 = 0.9993). This model accurately describes the oxidation process under diverse conditions, spanning variations in pO2 from 0.16 bar to 0.7 bar and β from 5 K/min to 20 K/min, and establishes a foundation for monitoring and controlling the oxidation dynamics of Mn-Fe particle for fluidized-bed heat transfer in CSP.

Dynamic Modeling and Analysis of a Disruptive Thermochemical Energy Storage Suitable for Linear Focus Solar Technologies

The industrial sector is a significant energy consumer, primarily reliant on fossil fuels. Nevertheless, the potential of Concentrated Solar Power (CSP) technologies for decarbonizing the industry is promising and the challenges posed by variability in weather and seasons can be effectively addressed through the use of seasonal storage methods, such as Thermochemical Energy Storage (TCES). This study presents a dynamic lumped-capacitance model, implemented in Dymola, designed to simulate a continuous suspension reactor employing salt hydrates like calcium oxalate monohydrate/anhydrous. The model mainly comprised (i) heat balances, (ii) reaction kinetics for the dehydration process and (iii) a heat transfer model. Furthermore, the study delves into a comprehensive case study involving the integration of CSP and TCES into a dairy processing facility located in Spain, addressing both daily operational requirements and seasonal energy storage demands. The solar field, heating demand, and storage tanks are described in detail. The transient simulation results for July showcase the efficacy of the solar installation and sensible energy storage for day-to-day operations, resulting in a total solar contribution of 47.3%. Notably, the thermochemical energy stored during this period can cover 22.1% of the low-temperature energy demand in January. The study underscores the importance of TCES in sustainable energy systems and paves the way for further optimization, economic assessment, and expanded applications. Future work will focus on enhancing the model and incorporating additional thermochemical materials, supported by additional experimental data.

Performance Evaluation of a 40-kWth Prototype Counterflow Particle-sCO2 Fluidized Bed Heat Exchanger

Particle-sCO2 heat exchangers (HXs) can couple particle-based thermal energy storage for concentrating solar power (CSP) plants with recompression closed Brayton power cycles (RCBC) to enable continuous dispatchable renewable electricity. RCBC firing temperatures >700°C require HXs with expensive Ni-based alloys, requiring HX designs to reduce mass with high overall heat transfer coefficients UHX to meet CSP primary HX cost. To enhance UHX, mild bubbling fluidization with downward particle flows and upward fluidizing gas flows can achieve particle-wall heat transfer coefficients hT,w >800 W m-2 K-1 with CARBOBEAD HSP 40/70. To assess how high hT,w with mild particle fluidization impacts UHX, a 40-kWth particle-sCO2 HX with 12-parallel narrow-channel fluidized beds was assembled and tested to particle inlet temperatures up to 530 °C. Tests show reliable steady-state HX operation by maintaining fluidized particles in a freeboard zone above the parallel channels, but axial dispersion mixes partially cooled particles up from the fluidized channels with particles fed into the freeboard zone from the feed hopper. This mixing lowers the effective bed temperatures and the driving force for heat transfer to counterflowing sCO2 in microchannelled walls. Measured UHX based on particle inlet temperature never exceeded 205 W m-2 K-1. The trade-off between increased hT,w, and increased vertical dispersion with gas flows resulted in only small improvements in UHX after the onset of fluidization. Dispersion was incorporated into HX design and performance models that used hT,w correlations fitted to single-channel heat transfer tests. Model results show that reducing dispersion leads to higher particle wall heat transfer.

NSTTF Heliocon Wireless Closed-Loop Controls Test Bed Development

A closed loop controls test bed is in development at the Sandia National Laboratories (SNL), National Solar Thermal Test Facility (NSTTF) as part of the U.S. DOE SETO sponsored Heliostat Consortium (HelioCON) program. This work pertains to preliminary development of advanced feedback controls for a concentrating solar power (CSP) field of 218 heliostats, and the development of a baseline closed-loop controls extremum seeking control (ESC) algorithm. This algorithm utilizes a batch least squares (BLS) technique to facilitate feedback control automation for heliostat pointing. This allows the determination of the optimal highest flux within a Gaussian profile, for both a four-point (QuadCell) aim point strategy, and a concentric aim point strategy. The results of this work determined that both approaches using the ESC BLS were able to reduce pointing errors to zero for both azimuth and elevation heliostat position movements. This work also reviews progress of the test bed which will allow flexible employment of controls and sensors which will be communicating with both wired and wireless protocols. The solar field distributed control system (DCS) will manage the flux distribution of energy across test articles and solar receivers using real-time programmable logic controllers (PLC) at each heliostat, for aiming and closed-loop feedback. Feedback control will be facilitated with a variety of sensors, located: 1. On the heliostat, 2. On the tower or 3. At an ancillary field tower station. The system is also developed to incorporate environmental information to provide real-time feedback into advanced algorithms for solar field management.

Thermo-economic investigation of transcritical Carbon Dioxide solar-thermal power plants, Part 1: System modeling and simulation for design with validation of results

This study comprises the engineering design and economic assessment of a novel trans-critical-point Carbon Dioxide cycle integrated with a solar Parabolic Trough Collector (PTC) power plant. A 1-MW facility with a Rankine transcritical CO2 cycle providing combined heat and power for a small industrial facility in Texas was proposed as the baseline power plant to perform the analysis. A design and modeling effort was performed in Engineering Equation Solver (EES) for the many systems and components of the power plant, including the solar field, the power block, and sub-components such as turbomachinery and heat exchangers. The model created enabled the simulation of plant performance for the median day of each month in the year by inputting meteorological TMY3 data, and results were extrapolated to estimate the annual energy and monetary income yield. Data processing was performed with MATLAB. Economic analysis included estimation of capital and O&M costs for the baseline plant. Results were verified through empirical performance simulation, using System Advisor Model (SAM), a software provided by NREL. The levelized cost of energy (LCOE) for the modeled plant was $0.2915/kWh, as calculated with EES/MATLAB, and $0.305/kWh, as calculated with SAM, resulting in a difference of less than 5%, between the two different simulation approaches. The design and simulation work presented herein provides the means to perform an optimization analysis, which reveals important clues as to how the energy cost could be reduced so as to make this technology a competitive alternative within the energy market.

Analysis of thermal and mechanical properties with inventory level of the molten salt storage tank in central receiver concentrating solar power plants

Molten salt thermal energy storage (TES) tanks ensure steady power output of concentrating solar power (CSP) plants; however, recent tank failures have highlighted the need for further analysis. Current studies primarily focus on analyzing the molten salt flow, heat transfer, and thermal efficiency. Additionally, research on the latest tank structures is limited and lacks newest experimental validation. This study measures temperature and molten salt inventory levels in the high-temperature tank at a 50 MW central receiver CSP plant, connected to the power grid in 2019. A multi-physics model was developed to evaluate thermal and mechanical properties of TES tanks by combining computational fluid dynamics and finite element modeling using real plant data. Heat loss, temperature, displacement, and stress distribution of the tank at different inventory levels were investigated. Results show that ambient air velocity near the tank roof reaches 2.14 m/s, much higher than 0.2 m/s near the wall. The temperatures of inventory fluid and tank are close, varying slightly at different levels due to thermal conduction and radiation. Because the heat loss strongly depends on temperature, the total tank loss remains nearly constant across inventory levels. Larger temperature gradients and thermal stresses are primarily localized along the tank floor edge and the air-salt interface. Notably, the maximum thermal stress at the tank edge is three times higher than that at the interface. The magnitude of total stress changes by less than 5 MPa with and without thermal load, indicating that high temperatures exert only a minor impact on tank stress. In contrast, thermal load significantly affects tank deformation, particularly at the roof edge, where values exceed 150 mm. Despite the large variation in molten salt levels, tank wall temperatures and displacements present a minor change, suggesting a weak correlation with inventory levels. The findings obtained in this study provide important insights on the TES tank that could be used to optimize tank design and operation strategies.

Amorphous Carbon Film as a Corrosion Mitigation Strategy for Stainless Steel in Molten Carbonate Salts for Thermal Energy Storage Applications.

Ternary carbonate salts (Li2CO3-Na2CO3-K2CO3) are promising heat transfer fluids to increase the efficiency of the electric power in concentrated solar power (CSP) technology. However, the corrosion produced at high operating temperatures is a key challenge to tackle for employing cost-effective steels as construction materials in CSP. In this work, the use of stainless steels with amorphous carbon was investigated, for the first time, as a surface modification method to mitigate the corrosion of structural CSP materials by molten salts. In doing so, an amorphous carbon (a-C) film of 100 nm in thickness was deposited on the 301LN stainless steel's surface by the carbon thread evaporation technique. The corrosion behavior of the 301LN was assessed in carbonate salt at 600 °C for 1000 h. This film decomposed forming carbide layers, contributing to corrosion mitigation due to the generation of denser oxide layers, decreasing the Li+ diffusion through the stainless steel.

High-Resolution Remotely Sensed Evidence Shows Solar Thermal Power Plant Increases Grassland Growth on the Tibetan Plateau

Solar energy plays a crucial role in mitigating greenhouse gas emissions in the context of global climate change. However, its deployment for green electricity generation can significantly influence regional climate and vegetation dynamics. While prior studies have examined the impacts of solar power plants on vegetation, the accuracy of these assessments has often been constrained by the availability of publicly accessible multispectral, high-resolution remotely sensed imagery. Given the abundant solar energy resources and the ecological significance of the Tibetan Plateau, a thorough evaluation of the vegetation effects associated with solar power installations is warranted. In this study, we utilize sub-meter resolution imagery from the GF-2 satellite to reconstruct the fractional vegetation cover (FVC) at the Gonghe solar thermal power plant through image classification, in situ sampling, and sliding window techniques. We then quantify the plant’s impact on FVC by comparing data from the pre-installation and post-installation periods. Our findings indicate that the Gonghe solar thermal power plant is associated with a 0.02 increase in FVC compared to a surrounding control region (p < 0.05), representing a 12.5% increase relative to the pre-installation period. Notably, the enhancement in FVC is more pronounced in the outer ring areas than near the central tower. The observed enhancement in vegetation growth at the Gonghe plant suggests potential ecological and carbon storage benefits resulting from solar power plant establishment on the Tibetan Plateau. These findings underscore the necessity of evaluating the climate and ecological impacts of renewable energy facilities during the planning and design phases to ensure a harmonious balance between clean energy development and local ecological integrity.

Integration of Thermal Solar Power in an Existing Combined Cycle for a Reduction in Carbon Emissions and the Maximization of Cycle Efficiency

The energy transition towards renewable energy sources is vital for handling climate change, air pollution, and health-related problems. However, fossil fuels are still used worldwide as the main source for electricity generation. This work aims to contribute to the energy transition by exploring the best options for integrating a solar field within a combined cycle power plant. Different integration positions at the gas and steam cycles for the solar field were studied and compared under several operating conditions using a thermodynamic model implemented in MATLAB R2024a. Fuel-saving and power-boosting (flowrate and parameter boosting) strategies were studied. The results revealed that, for a maximum fuel savings of 7.97%, the best option was to integrate the field into the steam cycle before the economizer stage. With an integrated solar thermal power of 3 MW, carbon dioxide emissions from fuel combustion were reduced to 8.3 g/kWh. On the other hand, to maximize power plant generation, the best option was to integrate the field before the superheater, increasing power generation by 24.2% for a solar thermal power of 4 MW. To conclude, guidelines to select the best integration option depending on the desired outcome are provided.