Clear Days Research Articles

Experimental Evaluation Study of the Comfort and Energy Performance of Suspended Particle Device Smart Windows in a Residential Building: Achieving Optimal Control during the Cooling Season

In contrast to traditional windows, smart windows dynamically affect indoor visual and thermal environments through Visible light transmittance (VT) and Solar heat gain coefficient (SHGC) changes. Therefore, for enhancing smart window application effects, it is necessary to analyze comprehensively the impacts of smart window tinting on indoor visual and thermal environments, and to establish appropriate tinting control methods. This study aimed to determine optimal smart window control strategies for residential buildings during the cooling season by evaluating visual and thermal comfort and energy performance in an actual building equipped with SPD smart windows. An experimental building was located in Sejong, South Korea (36.5°N latitude, 127.3°E longitude; temperate climate zone), and the measurements were conducted from July to August 2023 to compare glare, indoor daylight illuminance, thermal comfort, and cooling and lighting energy between typical and smart windows. And, optimal control methods were proposed from general comfort and energy performance perspectives. The measurements indicated that it was difficult to satisfy all aspects of the visual and thermal environment, and comprehensively it was recommended to employing “always tinting” on summer. However, on a clear day, jointly applying smart windows and lighting dimming control and controlling automatically based on indoor daylight illuminance levels were found to be the most effective as it not only secured visual comfort performance but also reduced lighting energy consumption.

Anomaly detection of photovoltaic power generation based on quantile regression recurrent neural network

Distributed photovoltaic (PV) power generation systems are widely spread. Moreover, due to the randomness of meteorological conditions and the complexity of installation environments, it is difficult to eliminate the interference of factors such as meteorological fluctuations in the monitoring of abnormal states of PV equipment. Based on this, this paper proposes a PV power generation anomaly detection method based on Quantile Regression Recurrent Neural Network (QRRNN). First, the characteristics of solar irradiance on clear days are analyzed, and the clear day masking method is used to eliminate the interference of cloudy and rainy weather. Then, the output correlation of different power stations is analyzed to obtain PV stations with high output correlation as the horizontal reference, which is used to exclude interferences such as permanent faults at the power stations. At the same time, vertical comparison of the output curves of the station under test on different clear days is conducted to eliminate interference factors such as weather and environmental conditions. Subsequently, the metered active power output data, which is free from interference, is input into the QRRNN model to obtain the normal active power output range of the PV. The power threshold of the normal output range is utilized to identify anomalies in PV power generation. Finally, simulation analysis of actual PV system data is conducted, and the results show that the method can effectively identify PV power generation anomalies and has high accuracy in PV fault detection.

Benchmark of estimated solar irradiance data at high latitude locations

Estimated solar irradiances from CAMS, PVGIS SARAH-2, Solargis, Meteonorm, PVGIS ERA5, and NASA POWER are benchmarked against measurements conducted at 34 ground stations in Norway at latitudes between 58 and 76°N. We find that the data products that mainly rely on high-resolution, geostationary satellite images, i.e., CAMS, PVGIS SARAH-2, and Solargis, have higher accuracy with lower relative Mean Absolute Error (rMAE) and relative Mean Bias Error. By dividing the stations in distinct categories, such as above 65°N, snow-affected and horizon-shaded, challenges with irradiance estimation that are common in Norway and at high latitudes in general are highlighted and discussed. The accuracy of the data products is dependent on latitude, and by excluding stations above 65°N, the median rMAE of the different data products improves 3.2 – 9.4 %abs compared to the median rMAE when including all stations, depending on data product. Similarly, by excluding snow-affected stations, the median rMAE improves 1.9 – 8.1 %abs, depending on data product. The improvement in rMAE by excluding snow-affected stations is partially related to the difficulty of separating snow on the ground from cloud cover in satellite images. This difficulty is illustrated by concrete examples of irradiance time series from clear sky days when the ground is covered in snow. Although the performance of the data products is dependent on the categorization of stations, i.e., latitude, snow conditions, and local topography, the relative performance between the products is maintained regardless of sub-division.

Evaluation of pedestrian thermal comfort from a whole-trip perspective: An outdoor empirical study

Pedestrian thermal comfort is a critical factor influencing urban livability and sustainability. However, existing models often overlook its cumulative impact from dynamic thermal experiences throughout the whole-trip. This study builds on previous findings, conducting outdoor mobile observations in Guangzhou's urban blocks on clear summer days. Methods for assessing thermal comfort during pedestrian travel were tested and refined, taking into account participants' skin temperatures and accumulated heat storage. The research found that the dynamic changes and non-uniform distribution of radiant temperature are the main characteristics of pedestrians' thermal experiences during summer clear weather and are critical factors affecting their thermal comfort. Non-uniform exposure to direct solar radiation can cause variations in pedestrians' instantaneous thermal sensations, and dynamic thermal experiences can lead to the formation of memorized thermal sensations, causing a deviation between instantaneous and whole-trip thermal sensations. There is a significant correlation between pedestrians' mean skin temperature and heat storage and their thermal experiences over the past 10–25 min. Regression analysis provided different weights that could represent the memory component in whole-trip thermal sensations. The findings provide a theoretical basis for understanding pedestrian thermal comfort in dynamic outdoor environments and will help improve the thermal quality of outdoor travel spaces.

Performance Assessment of Hybrid PV/PVT Collectors Incorporating Natural Water-Cooling Circulation

The present work investigates outdoor recitals and characteristics of hybrid PVT collectors and compares using non-cooled Photo-Voltaic (PV) collectors on a clear day at Khamshet, Pune, India. The hybrid PVT is designed, fabricated, and mounted on the terraces of the institute to ensure maximum radiation will fall on PV and PVT collector. The spiral circular thermal absorber is manufactured and placed at the backside of the photovoltaic to lower the surface temperature by extracting heat through water flowing through the absorber. The experimentation is performed at 0.03 kg/sec of water and natural cooling circulation is adopted for experimental work. The uncertainty analysis is also performed to ensure the accuracy of the results. The investigation observed that the PVT collector is superior to the PV system from electrical and thermal efficiency viewpoints. The cutback in PV module temperature was observed in a variation of 8.7-13.7%, which justifies using the water-cooling technique. The maximum electrical and thermal efficiency of 6.93 % and 52.7% were found for PVT collectors while sole maximum electrical efficiency of 5.62 % was found for PV collectors. This study concludes that the PVT collector has better performance characteristics than the PV collector and can be further enhanced using different fluid and thermal absorber designs.

Investigating the performance of an affordable parabolic dish collector with double glass vacuum cavity cover

Parabolic dish collectors (PDC) are one of the most important ways to concentrate solar energy. In this study, the performance of a low-cost parabolic dish collector with high average output temperatures is investigated. The low-cost PDC has a 45 ° edge angle and a circular receiver. A vacuum double-glazed cavity is used to keep heat inside the receiver and reduce the rate of heat losses. On clear and cloudy days, tests were conducted with thermal oil as a heat transfer fluid (HTF) to analyze the performance of the PDC. The results show that the change in temperature of the heat transfer fluid between the open and closed ends of the cavity receivers affected the receiver heat gain, thermal efficiency, and exergy efficiency. It was also found that the HTF has the highest exit temperature of 221 °C, with an average radiation intensity of 1032 W/m2. With 48.4 % thermal efficiency and 9.1 % exergy efficiency, the results showed the best performance. When it came to total efficiency, PDC showed its highest value of 46.2 % at 13:17 p.m. on January 4th, 2024.

Seasonal variation in vegetation cooling effect and its driving factors in a subtropical megacity

The urban heat island (UHI) effect has become a global issue, attracting widespread attention in recent years. Urban vegetation is an effective way to mitigate UHI through evapotranspiration (ET). However, the seasonal variation in vegetation cooling effect and its driving factors have not been well investigated. Therefore, the seasonal UHI intensity (UHII) on typical clear days in 2021 was calculated for Shenzhen based on the land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS). The slope between UHII and vegetation coverage was then used to characterize the vegetation cooling effect. Results showed that: (1) there is a significant negative linear correlation between UHII and vegetation coverage, with slopes mostly less than −1 and coefficients of determination (R2) larger than 0.4. (2) The slopes varied seasonally, indicating a larger vegetation cooling effect during summer daytime. A 10 % increase in vegetation coverage can reduce the daytime UHII by 0.16 °C in January and 0.59 °C in June, while at nighttime, the cooling effect varied between 0.12 °C in January and 0.27 °C in June. The daytime and nighttime UHII for the whole year can be reduced by 0.43 °C and 0.24 °C, respectively. (3) The seasonal variation in vegetation cooling effects during the daytime can be largely explained by that of ET, which is mainly driven by leaf area index (LAI).

The level, source, and health outcome of PM2.5 exposure in Southwest Iran

IntroductionDusty storms considerably increase airborne particles in dry and semi-dry locations, such as deserts with no plants and strong winds. Therefore, the environment and people are affected severely. Ahvaz, an important metropolis, is often polluted by neighboring nations. The present research studies the concentration, source, and calculation of these particles' effects. Material and methodFor health consequences evaluation, the WHO suggests the Air Quality Health Impact Evaluation Programmed (Air Q 2.2.3). Khuzestan Meteorology Office recorded particulate matter measurements on both hazy and clear days. The data was gathered voluminously in 2023. ResultAccording to data collected from Khuzestan province's meteorology documents, 49 days in 2023 had very unsafe air quality. The most polluted months in terms of the number of dust days are as follows: January (14 days) > December (12 days) > November (11 days) > August (5 days) > May (3 days) > September (2 days) > March, February, June, July, October (1 day) > April (0 days). HYSPLIT maps indicate that Iran causes dust in March, the Great Arabian Desert in December and August, Iraq in April, September, and October, Kuwait in January, Turkey in February and July, Egypt in June and May, and Oman in November. ConclusionThe meteorology database reveals that Ahvaz is highly polluted and that 49 days had unacceptable dust levels. Based on assessments obtained employing the Air Q+ programs, the people of Ahvaz encountered heart disease, respiratory disease, and stroke caused by their exposure to PM2.5 particulates.

Los colores del cielo

This manuscript describes the Olbers paradox, the Purkinje effect, and the Rayleigh and Mie theories of light scatte-ring, explaining their link with the black of the night, the white of the stars, the blue of a clear day sky, the yellowish co-lors of the Sun, the reddish of sunsets, and the milky appearance of clouds

Photochemical degradation of bisphenol S and its tetrahalogenated derivatives in water

Bisphenol S (BPS), a widely used plasticizer, is known to have potential endocrine disrupting effects to organisms. Its tetrahalogenated derivatives, tetrachlorobisphenol S (TCBPS) and tetrabromobisphenol S (TBBPS), are flame retardants exhibiting high neurodevelopmental toxicity and cytotoxicity. Halogen substitution has been shown to significantly affect the optical and photochemical properties of organic compounds. In this study, we conducted a comparative investigation into the photochemical behaviors of BPS, TCBPS, and TBBPS in aqueous solutions under both laboratory UV and natural sunlight irradiation. Spectroscopic titration results indicated that the pKa of TCBPS (4.16) and TBBPS (4.13) are approximately 3.7 units smaller than that of BPS (7.85), indicating that the halogenated derivatives are mainly present as the phenolate anions under circumneutral conditions. The halogen substituents also cause a significant bathochromic shift in the absorption spectra of TCBPS and TBBPS compared to BPS, leading to the enhanced absorption of sunlight. Meanwhile, TCBPS and TBBPS showed higher quantum yields than BPS, attributed to the "heavy atom" effect of halogen substituents. GCSOLAR modeling predicted half-lives for BPS, TCBPS, and TBBPS in surface water in Nanjing (32°2′7.3′′N, 118°50′21′′E) under noon sunlight in clear mid-autumn days as 810.2, 3.4, and 0.7 min, respectively. Toxicity evaluation suggest potential ecological risks of BPS/TCBPS/TBBPS and their photoproducts to aquatic organisms. Our findings highlight direct photolysis as an important mechanism accounting for the attenuation of tetrahalogenated bisphenols in both sunlit surface waters and UV based water treatment processes.engineered (e.g., UV disinfection) and natural aquatic environments (e.g., surface fresh waters).

Advancing sustainable cooling: Performance analysis of a solar-driven thermoelectric refrigeration system for eco-friendly solutions

The solar-powered thermoelectric refrigerator (SPTR) is an innovative approach that uses solar energy to cool spaces. Its effectiveness relies on solar insolation rates and an intelligent dual-axis solar tracking system (STS) that maximizes solar energy capture. Performance analysis of SPTR with the fixed panel solar system (WST) and dual-axis STS by keeping the SPTR at a standard ambient temperature of 25 °C was carried out under local climate conditions. The experimental test setup includes a thermoelectric refrigerator (TER), thermoelectric module (TEM), solar panels, and STS. The experimental findings showed that the coefficient of performance (COP) of SPTR depends on the solar irradiance, the system's input power, the surface temperature of the solar panels, and the cooling rate. The maximum and minimum values of COPs were 1.19 and 0.27 for directly coupled SPTR with a WST and 2.07 and 0.39 for STS, respectively. Compared with the stand-still solar system, a COP enhancement of 44–75 % is achieved. The results also show that the cooling load is a function of the refrigerated space, and the products are to be cooled, which is affected by the thermoelectric properties of the TEM. The cooling rate is recorded at its maximum when the system is operated using an STS on a clear sunny day with a maximum solar insolation rate. The SPTR has proven to be environmentally friendly, the best alternative to conventional cooling systems, and sustainable due to the independence of traditional energy resources.

Assessing the Convective Environment over Irrigated and Nonirrigated Land Use with Land–Atmosphere Coupling Metrics: Results from GRAINEX

Abstract Land-use land-cover change affects weather and climate. This paper quantifies land–atmosphere interactions over irrigated and nonirrigated land uses during the Great Plains Irrigation Experiment (GRAINEX). Three coupling metrics were used to quantify land–atmosphere interactions as they relate to convection. They include the convective triggering potential (CTP), the low-level humidity index (HIlow), and the lifting condensation level (LCL) deficit. These metrics were calculated from the rawinsonde data obtained from the Integrated Sounding Systems (ISSs) for Rogers Farm and York Airport along with soundings launched from the three Doppler on Wheels (DOW) sites. Each metric was categorized by intensive observation period (IOP), cloud cover, and time of day. Results show that with higher CTP, lower HIlow, and lower LCL deficit, conditions were more favorable for convective development over irrigated land use. When metrics were grouped and analyzed by IOP, compared to nonirrigated land use, HIlow was found to be lower for irrigated land use, suggesting favorable conditions for convective development. Furthermore, when metrics were grouped and analyzed by clear and nonclear days, CTP values were higher over irrigated cropland than nonirrigated land use. In addition, compared to nonirrigated land use, the LCL deficit during the peak growing season was lower over irrigated land use, suggesting a favorable condition for convection. It is found that with the transition from the early summer to the mid/peak summer and increased irrigation, the environment became more favorable for convective development over irrigated land use. Finally, it was found that regardless of background atmospheric conditions, irrigated land use provided a favorable environment for convective development.

Validating Meteosat Second Generation and Himawari-8 Derived Solar Irradiance against Ground Measurements: Solarad AI’s Approach

This study assesses the efficacy of the Heliosat-2 algorithm for estimating solar radiation, comparing its outputs against ground measurements across seven distinct countries: the Netherlands, Spain, Japan, Namibia, South Africa, Saudi Arabia, and India. To achieve this, the study utilizes two distinct satellite data sources—Himawari-8 for Japan and Metosat Second Generation-MSG for the rest of the countries—and spanning the time between January 2022 and April 2024. A robust methodology for determining albedo parameters specific to Heliosat-2 was developed. During cloudy days, the estimates provided by Heliosat-2 generally exceeded the ground measurements in all of the countries. Conversely, on clear days, there was a tendency for underestimation, as indicated by the median values of the mean bias (MB) across most of the countries. The Heliosat-2 model slightly underestimates daily radiation values, with a median MB ranging from −27.5 to +10.2 W·m−2. Notably, the median root mean square error (RMSE) on clear days is significantly lower, with values ranging from 24.8 to 108.7 W·m−2, compared to cloudy days, for which RMSE values lie between 75.3 and 180.2 W·m−2. In terms of R2 values, both satellites show strong correlations between the estimated and actual values, with a median value consistently above 0.86 on a monthly scale and over 92% of daily data points falling within ±2 standard deviations.

Ratio of photosynthetically active radiation to global solar radiation above forest canopy in complex terrain: measurements and analyses based on Qingyuan Ker Towers

BackgroundUnderstanding of the ratio of photosynthetic photon flux density (Qp) to global solar radiation (Rs) (Qp/Rs) is crucial for applying Rs to ecology-related studies. Previous studies reported Qp/Rs and its variations based on measurements from a single observatory tower, instead of multi-site-based measurements over complex terrains. This may neglect spatial heterogeneity in the terrain, creating a gap in an understanding of how terrain affects Qp/Rs and how this effect interacts with meteorological factors.MethodsHere the Qingyuan Ker Towers (three towers in a valley with different terrains: T1, T2, and T3) were utilized to measure Qp and Rs over mountainous forests of Northeast China. An airborne LiDAR system was used to generate a digital elevation model, and sky view factor of sectors (SVFs) divided from the field of view of tower’s pyranometer was calculated as a topographic factor to explain the variations of Qp/Rs.ResultsThe results identified significant differences in Qp/Rs of the three towers at both daily and half-hour scales, with larger differences on clear days than on overcast days. Qp/Rs was positively correlated with SVFs of T1 and T3, while this correlation was negative with that of T2. The effect of SVFs on Qp/Rs interacted with clearness index, water vapor pressure and solar zenith angle. Random forest-based importance assessment demonstrated that explanation (R2) on Qp/Rs was improved when SVFs was included in the predictor variable set, indicating that incorporating terrain effects enhances the prediction accuracy of Qp/Rs. The improvement in the R2 values was more pronounced on clear days than on overcast days, suggesting that the effect of terrain on Qp/Rs depended on sky conditions.ConclusionsAll findings suggested that Qp/Rs is affected by terrain, and integrating terrain information into existing Qp/Rs models is a feasible solution to improve Qp/Rs estimates in mountainous areas.

The effects of solar insolation and cloud opacity on the optimum array size for a direct-coupled solar pumping system

The widespread adoption of solar photovoltaic pumping technology requires pertinent information on the sizing and design of these systems. This research investigated how the ratio of photovoltaic array peak power to motor power consumption, solar insolation and cloud opacity affects the water yield of a direct-coupled solar PV pumping system. The specific aim was to estimate the optimum photovoltaic power to motor power consumption (OPVM) ratio for a 3 W DC pump under Jamaican weather conditions. The PVM ratio is the ratio of peak array power to nominal motor power consumption. Four experimental direct coupled solar pumping systems were set up and the water yield for each measured daily for thirty days. Each system was identical in every respect except each having a different solar array peak power. The findings show that there is a strong correlation (Pearson coefficient of −0.903) between solar insolation and the optimum photovoltaic power to motor power consumption ratio. Additionally, there was found to be a strong correlation between average cloud opacity and optimum photovoltaic power to motor power consumption ratio (Pearson coefficient of 0.899). Both correlations were shown to be statistically significant, with both yielding p-values <0.001. The findings of the correlation analysis indicate that a relatively large PVM ratio would be economical when used on a site that regularly receives relatively low insolation and heavy cloud cover. Finally, the daily optimum photovoltaic power to motor power consumption ratio ranged from approximately 2.3 to 5.0. Generally, it was observed that the OPVM ratio shifted below 2.4 on clear sunny days and above 4.0 on very cloudy days. While these conclusions may not exactly extrapolate to scales of practical application, performance metrics of larger systems are expected to bear some similarity. Being guided by these results, additional studies at these larger scales are recommended.

The performance of floating Photovoltaic system over a small pond in Jakarta.

It is recognized that photovoltaic (PV) cells exhibit a drawback when subjected to significant temperature increases. This paper presents an initial study of the performance of Floating PV (FPV) over a pond, encompassing the effect of the PV panel’s surface temperature on the variation of the PV cell efficiency. To facilitate this study, an experimental study was conducted. The experiment deployed four monocrystalline PV panels with a maximum power output (Pmax) of 100 Watts for each panel. These four panels were divided into two sets that each set contain two PV panels. The first set was installed over a small pond with an area of 24 m2 and a depth of 1.2 m, while the other set was placed over a concrete surface with the same area size. The steps of the experiment study were as follows: (1) to measure the PV panel’s surface temperature of the two sets, and (2) to calculate the operating PV cell efficiency using an energy balance equation. The measurement of the PV panel’s temperature was taken hourly from 08.00 AM to 04.00 PM on clear and cloudy day. The data on rainy day was excluded. The study was conducted in an urban area of Jakarta, where the average ambient temperature ranges between 25°C and 30°C. The experimental site conditions are relatively clear, only several trees located on the south of the area. The results indicated that pond has a significant effect on the reduction of the PV panel’s surface temperature as compared to the PV set over the concrete surface. The average temperature reduction is around 3.5°C on a clear day, whereas the maximum reduction is 7.8°C, when the irradiance level rises to around 1000 W/m2. Indeed, the observed improvement of the PV cell efficiency was approximately 3.9% at the highest and in average was around 2%.

Performance evaluation and economic analysis of inclined solar dryer for Capsicum annuum L. (Red chilli) drying

This study presents an assessment of the performance and economic viability of solar dryers for drying perishable agricultural products. The dryer was constructed using locally sourced materials such as galvanized iron sheet, M.S. angle, glass, and S.S. wire mesh. The ability to tilt the dryer allows for optimal solar radiation absorption throughout the year in Jodhpur, India. It is well-established that a tilted surface captures more solar radiation compared to a horizontal plane, hence the utilization of a solar dryer in this research. A drying experiment was carried out in January 2023 using the dryer to dehydrate red chilli (Capsicum annuum L.). The maximum stagnation temperature inside the drying chamber was recorded at 65°C, which decreased to 55°C when loaded with 10 kg of chilli, while the outside ambient temperature was 26°C on a clear sky day (from 08:00 h to 18:00 h) in January 2023. Over the course of seven days, the moisture content of the chilli decreased from 80% (wet basis) to approximately 9%. The open sun drying method took 14 days for reducing the moisture content of red chillies to the same level. The dryer's thermal efficiency was calculated to be 16.25%. The economic analysis of the solar dryer indicated a high internal rate of return (IRR) of 82.5% and a short payback period of 1.50 years, highlighting its cost-effectiveness. The cost-benefit ratio was found to be 1.98, demonstrating the potential of solar dryers as a substitute for traditional drying methods. Economic parameters such as net present value (₹40220) and system annuity (₹5430) confirmed the economic feasibility of the system. Inclined solar dryers in remote or rural areas have the potential to significantly reduce postharvest losses and carbon emissions. The adoption of solar dryers would greatly benefit farmers in the arid region of Rajasthan.

Investigating turbulence distribution in the lower atmosphere using time-lapse imagery from a camera bank

The atmosphere’s surface layer (first 50–100 m above the ground) is extremely dynamic and is influenced by surface radiative properties, roughness, and atmospheric stability. Understanding the distribution of turbulence in the surface layer is critical to many applications, such as directed energy and free space optical communications. Several measurement campaigns in the past have relied on weather balloons or sonic detection and ranging (SODAR) to measure turbulence up to the atmospheric boundary layer. However, these campaigns had limited measurements near the surface. We have developed a time-lapse imaging technique to profile atmospheric turbulence from turbulence-induced differential motion or tilts between features on a distant target, sensed between pairs of cameras in a camera bank. This is a low-cost and portable approach to remotely sense turbulence from a single site without the deployment of sensors at the target location. It is thus an excellent approach to study the distribution of turbulence in low altitudes with sufficiently high resolution. In the present work, the potential of this technique was demonstrated. We tested the method over a path with constant turbulence. We explored the turbulence distribution with height in the first 20 m above the ground by imaging a 30 m water tower over a flat terrain on three clear days in summer. In addition, we analyzed time-lapse data from a second water tower over a sloped terrain. In most of the turbulence profiles extracted from these images, the drop in turbulence with altitude in the first 15 m or so above the ground showed a h m dependence, where the exponent m varied from −0.3 to −1.0, quite contrary to the widely used value of −4/3.

Dynamic Monitoring and Analysis of Dual-Axis movement of SPV Power Plant Parameters under various Atmospheric Conditions

This research paper presents comprehensive insight into the testing of a 1 KW sun tracking photovoltaic (PV) performance. The study uses a state-of-the-art real-time string monitoring system to allow this analysis while covering an extensive variety of atmospheric conditions. The design of the 1 KW solar tracker system incorporates a tracking sensor circuit, motor driver circuit, string monitoring system, and solar tracker control circuit. Solar tracking systems boost energy generation by adjusting the angle of PV panels to optimum sunlight exposure. The effectiveness of such devices can, however, be severely impacted by atmospheric changes. In a photovoltaic (PV) facility, we have successfully developed and placed into use a real-time system for monitoring certain strings. The system collected data on key parameters such as current, voltage, and temperature, providing insights into the health and efficiency of each string. Our study encompassed various atmospheric conditions, including clear skies, cloudy days, and fluctuating solar radiation. A DAQ system developed communicate with observations such as the voltage and current of photovoltaic arrays and the voltage and current of DC motors. When comparing the dual-axis tracking system to the static PV system, a maximum of 48% more electricity can be extracted. Both days with clear skies and days with clouds provide satisfactory results. The supply for the tracker control circuit comes from PV cells. Therefore, there is no need for any auxiliary supply, such as a battery.

Development of the Generation 3 Particle Pilot Plant Falling Particle Receiver

A falling particle receiver (FPR) has been designed to integrate with the G3P3-USA pilot plant currently being constructed at the National Solar Thermal Test Facility (NSTTF) at Sandia National Laboratories. This receiver integrates several innovative design features including a converging tunnel (SNOUT), an optimized cavity geometry, and a multistage “catch-and-release” trough. Details about the integration of these features and the final G3P3-USA FPR design and construction are described. Ray-tracing models of the FPR utilizing the NSTTF heliostat field are developed leveraging previous modeling efforts using SolTrace. Models demonstrate that at least 1.5 MWth of incident radiative energy can be provided to the FPR on a clear day throughout a typical year in Albuquerque, NM. Spillage fluxes around the periphery of the aperture are within acceptable bounds for the majority of the year. Intercept factors are computed for each utilized heliostat at the Vernal equinox to provide guidance to heliostat operators during operation of the system.