Application In Solar Power Plants Research Articles

Antimicrobial polymer composites with anti-biofouling features for floating solar power plant applications: Effect of zinc oxide nanoparticles

Antimicrobial hybrid polymer composites are developed for application in floating solar power plants. To avoid the degradation of the floater because of microbes living in the water as well as possible biofouling, zinc oxide (ZnO) is used as an antimicrobial agent, varying the weight percent (1, 2, and 3 wt%) within the high-density polyethylene (HDPE) matrix, along with carbon black (CB) as a reinforcing agent (1, 1.5, 2, and 2.5 wt%). Escherichia coli (facultative anaerobic) and Pseudomonas aeruginosa (aerobic-facultatively anaerobic) gram-negative bacteria formed a biofilm on HDPE in a 96-well plate for 5 days. In vitro, biofilm formation was determined by measuring absorbance (A420) in crystal violet dye, and the colony-forming unit (CFU) was determined by the spread plating technique. The biofilm formation and disruption are observed through a scanning electron microscope (SEM), where both the CFU and the SEM revealed uniform formation of biofilm onto neat HDPE. The best performance in terms of reduced biofilm formation and biofouling onto HDPE floaters was achieved for E. coli (ZnO: 2 wt% and CB: 2 wt%), whereas for Pseudomonas aeruginosa (ZnO: 3 wt% and CB: 2 wt%). Application of greener polymers and nanoparticles for future studies is highly recommended.

The Design of Solar Cell-Based Street Lighting for School Area

Currently, public street lighting using Solar-based Public Street Lighting has been widely used. Solar-based Public Street Lighting is an off-grid Solar Power Plant application for street lighting. This study aims to use Solar-based Public Street Lighting which has been designed for Inayah Islamic School according to the geographical features of the school. To design this Solar-based Public Street Lighting by considering the economic aspect. From the data obtained directly at the location, the road width is 4.5 meters and the total length is 330 meters. Road size is used to determine the need for lighting quality according to the Indonesian National Standard of 7391:2008. This Solar-based Public Street Lighting has been designed with a pole height of 5 meters and a 1.5-meter pole arm using a 20 Watt 2-in-1 LED lamp and a solar cell capacity of 50 Wp per pole. From the results of the design analysis, the component specifications used in the design have met the requirements according to SNI of 7391:2008, and the required poles for Solar-based Public Street Lighting are 22 points for the Inayah Islamic School Complex area

Thermochemical energy storage using coupled metal hydride beds of Mg-LaNi5 composites and LaNi5 based hydrides for concentrated solar power plants

• A MHTES system is proposed for CSP plant application. • Energy storage and recovery temperatures are estimated. • PCIs of Mg based composites and LaNi 5 based alloys are measured. • Reaction enthalpy and entropy are evaluated using van’t Hoff equation. • The performance of the MHTES system is analyzed thermodynamically. • The effect of operating temperatures on the performance of the MHTES is studied. Thermochemical energy storage based on coupled hydride beds is an attractive option for Concentrated Solar Power plant applications due to its efficient long term and high energy storage density. In the coupled system, a high temperature metal hydride (HTMH) bed is coupled with a low temperature metal hydride (LTMH) bed. In the present study, Mg-LaNi 5 composite hydrides are taken as HTMHs due to their high absorption capacity and high reaction enthalpy, and LaNi 5 based alloys are taken as LTMHs as these hydrides are ideal for hydrogen storage at ambient conditions. The thermodynamic properties such as reaction enthalpy and entropy are evaluated by measuring Pressure Concentration Isotherms of Mg- x wt% LaNi 5 ( x =20 and 30) composites, LaNi 4.7 Al 0.3 and LaNi 4.6 Al 0.4 . A new methodology for storing and recovering thermal energy together with upgradation of the quality of energy is established. Methodology to determine the minimum energy storage temperature and maximum energy recovery temperature is proposed. The quality of the thermal energy will be improved by increase in delivery temperature. Thermodynamic analysis is performed using measured properties to evaluate the performance parameters such as heat upgradation, coefficient of performance (COP), and energy storage density (ESD). Maximum COP and ESD of 0.705 and 418.841 kJ/kg, respectively is obtained for hydride pair Mg-5wt% LaNi 5 -La 0.8 Ce 0.2 Ni 5 . Maximum degree of upgradation of 34°C is obtained using the hydride pair Mg-20wt% LaNi 5 -LaNi 4.7 Al 0.3 . The effects of variation of heat source temperature, regeneration temperature and ambient temperature on the performance of the MHTES is studied. It is observed that the regeneration temperature is a significant parameter that influences the performance of the MHTES.

Operating Characteristics of Metal Hydride-Based Solar Energy Storage Systems

Thermochemical energy storage systems, based on a high-temperature metal hydride coupled with a low-temperature metal hydride, represent a valid option to store thermal energy for concentrating solar power plant applications. The operating characteristics are investigated for a tandem hydride bed energy storage system, using a transient lumped parameter model developed to identify the technical performance of the proposed system. The results show that, without operational control, the system undergoes a thermal ratcheting process, causing the metal hydride concentrations to accumulate hydrogen in the high-temperature bed over time, and deplete hydrogen in the low temperature. This unbalanced system is compared with a ’thermally balanced’ system, where the thermal ratcheting is mitigated by thermally balancing the overall system. The analysis indicates that thermally balanced systems stabilize after the first few cycles and remain so for long-term operation, demonstrating their potential for practical thermal energy storage system applications.

Design and Implementation of Boost Voltage Doubler for Maximum Power Point Tracker Application Using STM32F1038CT

Photovoltaic is an absolute device in the solar power plant system. A DC-DC converter with a maximum power point tracker (MPPT) algorithm is required to obtain the maximum power of photovoltaic. In general, solar power plant applications used a two-stage converter: the first stage is boosting DC-DC converter, and the second stage is the multilevel Inverter. Boost DC-DC converter is usually implemented singly, which causes many boost DC-DC converters to be implemented in a solar power plant application. The voltage doubler type boost DC-DC converter proposed in this paper is to simplify the circuit so that there is only one converter in a solar power plant application. This converter principle combines two conventional boost converters, which are integrated into one so that the power circuit and control circuit form become simpler. This proposal is verified through computation simulation and hardware design using the STM32F1038CT microcontroller for the final verification. The efficiency algorithm of the simulation is 99.7%, and the hardware experimental is 85.65%

Corrosion behavior of SS316L in ternary Li2CO3–Na2CO3–K2CO3 eutectic mixture salt for concentrated solar power plants

This paper elaborates the compatibility of SS316L alloy with LiNaK carbonate for concentrated solar power plant applications. In this study, corrosion behavior and corrosion mechanism of SS316L in the eutectic LiNaK carbonate molten salt, at 600 °C and 700 °C, were investigated in detail. The results revealed that the corrosion process of stainless steel 316L in the LiNaK carbonate molten salt is mainly divided into four successive steps: (i) selective oxidation process of metals → (ii) lithiation reaction of the oxide → (iii) formation of a dual-structured corrosion scale → (iv) separation and spalling of corrosion products. Moreover, increasing temperature to 700 °C results in a severe corrosion of SS316L in the molten carbonate salt. Therefore, it is imperative to explore a suitable protective coating for SS316L to use it as a structural material in concentrated solar power plant.

Natural convection of hybrid nanofluids inside a partitioned porous cavity for application in solar power plants

The present article deals with the CFD simulation of natural convection heat transfer of a hybrid nanofluid in an inverted T-shaped cavity partitioned and saturated by two different types of porous media. Suspensions of organic and inorganic nanoparticles, i.e., MWCNTs and Fe3O4, in water were selected as the working fluid. The macroscopic conservation equations for the flow field and heat transfer were modeled via volume averaging the microscopic equations inside porous media over a representative elementary volume. The effects of many parameters were investigated. The parameters included the Rayleigh number (Ra = 103–106), porosity coefficient ratio of two porous media (er = 0.5–1.8), volume fraction of the dispersed nanoparticles ( $$\varphi$$ = 0–0.003), Richardson number (Ri = 0.1–20), Darcy number ratio of two porous media (Dar = 0.01, 1, 100) and thermal conductivity ratio of two porous media (kr = 0.2, 0.4, 1, 5). The results showed that, with an increase in the Rayleigh number, porosity ratio and Darcy number ratio and decrease in the thermal conductivity ratio, the averaged Nusselt number increased.

Analysis of Changes in Temperature and Irradiance to DC-DC Buck Converter Based on IP Controller for Solar Power Plant Application

This paper presents a mathematical model of photovoltaic with buck converter to analyze the voltage and current as a result of radiation and temperature changes as the input signal. Photovoltaic simulator models created using the C programming integrated with Matlab Simulink. The IP controller is used to control the current of a buck converter with the reference current from the dynamic model of photovoltaic. The control signal from the IP controller is used for generating a PWM signal, which is used to drive the IGBT gate of the buck converter. Input of irradiance and temperature are given to the photovoltaic simulator. Moreover, the current and voltage of the buck converter are used as a feedback to the photovoltaic simulator. This experiment is run through the system in real time and the simulation results show that changing in radiation has more significant effect on the output voltage of a solar power system compared to changing in temperature.

Numerical Investigation of PCM-based Thermal Energy Storage System

Abstract A latent thermal energy storage system, which consists of sodium nitrate filled spherical capsules in a cylindrical tank, is analyzed for concentrating solar power plant applications. The high temperature synthetic oil, Therminol 66, is used as heat transfer fluid. A numerical model is developed to investigate the behavior of the system. The developed model is validated using the reported experimental and numerical data. The influence of capsule size and the flow rate of heat transfer fluid (HTF) on the temperature distribution, fluid flow, melting and solidification of the system is studied. The natural convection effect present in the liquid region during melting is resolved by the effective thermal conductivity, which is calculated by enthalpy formulation method. The results indicated that the heat transfer rate is increased and eventually the charging/discharging time is decreased when the capsule size is decreased, or the HTF flow rate is increased.

Geometric Modularity in the Thermal Modeling of Solar Steam Turbines

To optimize the start-up schedules of steam turbines operating in concentrating solar power plants, accurate predictions of the temperatures within the turbine are required. In previous work by the authors, thermal models of steam turbines have been developed and validated for parabolic trough solar power plant applications. Building on these results, there is an interest to increase the adaptability of the models with respect to different turbine geometries due to the growing trend of having larger steam turbines in parabolic trough and solar tower power plants. In this work, a modular geometric approach has been developed and compared against both the previous modeling approach and 96h of measured data from an operational parabolic trough power plant. Results show a large degree of agreement with respect to the measured data in spite of the different detail levels. The new model allows for simple and fast prediction of the thermal behavior of different steam turbine sizes and geometries, which is expected to be of significant importance for future concentrating solar power plants.

Absorber Layer Addition and Thermal Storage Media Comparison for Concentrated Solar Power Plant Optimization

Electricity generation from concentrated solar power plant can be optimized on its storage system or its receiver system. This paper conducts a review of how to optimize the concentrated solar power plant by increasing the stored energy capacity or by stabilizing the absorptance and emittance in the solar absorber. The additional stages in the CSP may increase thermal efficiency. The stages consist of two oriented solar absorber to create superheated steam fed to the steam turbine and one regenerator to optimally regenerate heat for working fluid before pumped to solar absorber. A suitable treatment for superheated steam from solar absorber can optimally supply the turbine with a continually stable steam. The continuous stable steam can be controlled using steam accumulator right before the superheated steam fed into turbine. The thermal energy storage in the cycle can be optimally selected based on the stored energy capacity per kg of compared material used. The final modification was made using recently developed absorber material of hafnium molybdenum nitride to create four layer tandem absorber of HfMoN(H)/HfMoN(L)/HfON/Al2O3. The tandem absorber indicates a stable absorptance and emittance up until 600°C (in vacuum) and 525°C (in air). The final configuration believed to enhance the thermal stability for high temperature concentrated solar power plant application.

A numerical thermal approach to study the accelerated aging of a solar absorber material

Solar power tower receivers are exposed to highly-concentrated solar flux. The strong flux variations that they are exposed to during their service life enhance the physical–chemical aging mechanisms and cause the decrease of the material’s thermal performance. A material that is commonly used for these applications was selected for our study. It is used for the absorber tubes of a solar power tower receiver. This material is made of an alloy (Inconel 625) that is coated with a silicone-based paint coating (Pyromark 2500 black) to increase the solar radiation absorption capacity.With the aim of determining the optimal conditions to accelerate the aging of this two-layer material (metal+paint coating), an axisymmetric 2-D model reproducing its thermal behavior was developed. Several thermal indicators (temperature, thermal gradients, temporal gradient), which are representative of the thermal aging factors and the material’s thermal performance, are analyzed in different configurations of boundary conditions. One configuration was defined according to the normal working conditions of a particular solar power plant application; the others are associated with various boundary conditions with the potential to increase or modify the thermal stress factors to accelerate the aging mechanisms. Other aging factors such as humidity, pollutants, and dust are not investigated in this paper. Several simulations were run in permanent and variable regimes. The most influencing boundary conditions and material properties were highlighted by a sensitivity study. To design relevant aging tests, particular attention should be paid to the incident solar power and the cooling characteristics of the material. The surface total absorptance, the thermal conductivities and the thermal contact resistance between the paint and the metal layers are the parameters that most affect the material’s thermal behavior. The evolution of those material properties characterizes the aging and should be monitored. Irradiance cycles were simulated for their potential to increase the thermal fatigue. Depending on the average, the amplitude and the period of the cycle, the evolution of the thermal indicators were analyzed. They were compared to select the most appropriate aging tests that are to be performed. From there, two aging strategies were determined. To put them in practice, an experimental Solar Accelerated Aging Facility (SAAF) was built and is described in this paper. It enables to perform accelerated aging experiments with a 2-m-diameter parabola concentrating the sun radiation up to 16,000 times. A preliminary experiment to validate the model confirmed that the simulation results are in good agreement with the experimental.