Average Solar Radiation Research Articles

Thermal Evaluation of Solar Dryer’s Curve-Front utilized Heat Transfer Analysis

The sun is most sustainable renewable energy, environmentally friendly and utilized for preservation of food and agricultural crops. The main objective of this experiment research work has focused on using renewable energy for evaporated moisture of foods fruit vegetables and herbs by drying system. The heat transfer equation are analyzed to effectively harness the temperature from the sun. Experimental data obtained were used to evaluate the properties of dry air on boundary region condition. Initial, testing was carried out under without load condition, and the result shows that the ambient and dryer’s internal temperature range between 29.3-40.2˚C and 37.4-60.3 ˚C, respectively, in Thailand a latitude of 14°0'48.46" North and longitude of 100°31'49.76" East (recorded average solar radiations and temperature on January 2023 - June 2024), average solar radiations range between 312 W/m2 and 513 W/m2. The indirect natural convection was design and calculated energy base on average temperature not higher than 55˚C, utilized sun daylight at 08:00 a.m. to 04:00 p.m. local time and clear sky or partially cloudy. Second, determination of design parameters; heat energy equation and steam table analysis. Final, utilization of the design under local time, solar radiation and the climatic local conditions and test with ginger slices (represent product in order to examine weight loss). The solar dryer’s curve front shape conduced on without load showed the heat transfer coefficient natural convections range between 3.7 and 4.5 W/m2 ˚C, the energy of dry air analysis range between 54.7 and 155.2 J/s and performance of drying rate range between 0.06 and 0.82 g/s, under increasing and decreasing trends of solar radiations from the time, date and climatic local region condition.

Thermal Performance of Novel Eco-Friendly Prefabricated Walls for Thermal Comfort in Temperate Climates

The global threat of climate change has become increasingly severe, with the efficiency of buildings and the environment being significantly impacted. It is necessary to develop bioclimatic architectural systems that can effectively reduce energy consumption while bringing thermal comfort, reducing the impact of external temperatures. This study presents the results of a real-scale experimental house prototype, MHTITCA, using a unique design composed of novel eco-friendly prefabricated channel walls filled with a blend of soil, sawdust, and cement for walls and roofs. The experimental analysis performed in this study was based on dynamic climatology. A solar orientation chart of the place was constructed to identify the solar radiation intensity acting on the house. Measurements of roof surface temperatures were conducted to determine temperature damping and temperature wave lag. Monthly average temperature and direct solar radiation data of the site were considered. Compared to other alternative house prototypes, the system maximizes thermal comfort in high-oscillation temperate climates. Temperature measurements were taken inside and outside to evaluate the thermal performance. A thermal insulating layer was added outside the wall and the envelope to improve the prototype’s thermal comfort and reduce the decrement factor even more. This MHTITCA house prototype had 85% thermal comfort, 0% overheating, and 15% low heating. This eco-friendly prototype design had the best thermal performance, achieving a thermal lag of twelve hours, a reduced decrement factor of 0.109, and preventing overheating in areas with high thermal fluctuations. Comparatively, the other prototypes examined provided inferior thermal comfort. The suggested MHTITCA system can be an energy-saving and passive cooling option for thermal comfort in low-cost houses in temperate climates with high thermal oscillations in urban or rural settings.

Design, modeling and cost analysis of 8.79 MW solar photovoltaic power plant at National University of Sciences and Technology (NUST), Islamabad, Pakistan

Climate change, as a critical global concern, has fueled our efforts to address it through different strategies. In response to the critical worldwide issue of climate change, we suggested a Photovoltaic (PV) system at the National University of Sciences and Technology (NUST) in Islamabad, Pakistan (latitude: 33.724530 N, longitude: 73.046869, terrain elevation: 552 m). Islamabad is located in a region blessed with enormous solar resources, boasting a daily horizontal solar irradiance of 1503.45 kWh/m2 and an average daily solar irradiance of 5.89 kWh/m2, with an exceptional solar fraction of 98.99%. The ambient air temperature, averaging 23.21 °C, reaches its maximum in June and its minimum in December. Our research thoroughly evaluates the system’s performance, accounting for various losses and utilizing modern PVsyst software. Over the course of 18 years, our PV system is expected to save 75,478.60 tons of CO2, the equivalent of planting 348,754 teak trees. Furthermore, the cost of energy generation is an affordable 0.0141 US $/kWh, much lower than traditional rates, including the Sherif cost of 0.028$/kWh. Along with the performance research, we conducted a detailed cost analysis, projecting the starting cost and cash flow, and discovered that the plant would be in surplus within 12 years of installation. Our system is positioned to generate 11,270,771 kWh/year with a respectable performance ratio (PR) of 76.2% and a Capacity Utilization Factor (CUF) of 16%. Our findings not only highlight the potential of renewable energy but also provide important insights for future sustainable energy programs.

Graphene Coating and its Effect on Performance of Box Type Solar Cooker: An Experimental Investigation

Background: Solar cookers have been the subject of several theoretical and empirical investigations, with numerous modifications attempted to increase efficiency and security. Solar cookers need much sophisticated research and enhancement work to function better. A thorough grasp of the application of graphene in box-type solar cooking systems is crucial for both solar energy and graphene. Objective: To improve the performance of box-type solar cookers, this patent research aims to offer an experimental investigation and insightful information on of applying graphene coating to the absorber plate and its derivative. Materials and Methods: To ensure equal dispersion of graphene into the black paint, three samples containing (1, 3, and 5wt%) of graphene embedded with the paint were produced with 1mm, 3mm, and 5mm thickness of the coating and stirred at 400 rpm for two hours using a magnetic stirrer. Xray diffraction and scanning electron microscopy have been studied to comprehend the influence of graphene nanoparticles on the surface morphology of the coated absorber panel. Performance evaluations of the box-type solar cookers were conducted with and without a graphene coating on the absorber plate, and data has been recorded for each case. Results: The results of patent research show that the absorber plate with (1, 3, and 5wt.%) of graphene embedded with black paint 1mm, 3mm, and 5mm thickness coating has a maximum thermal efficiency of 41.48% with 97.08 W cooking power, 46% with 109.35 W cooking power, and 49% with 114.77 W cooking power for the average solar irradiation is 978 W/m2. Discussion: It was determined that the cooking power (P), the first figure of merit (F1), and the second figure of merit (F2) were all satisfactorily achieved. Embedding black paint into graphene coating has been shown to significantly influence the heat transmission and thermal performance enhancement of box-type solar cookers, as demonstrated by the findings of X-ray diffraction and Scanning Electron Microscopy analysis. Conclusion: The current research makes it abundantly evident that the incorporation of graphene into the absorber plate of a box-type solar cooker, together with the application of a black paint coating, leads to increased heat transfer rates, which in turn provides an increase in cooking power. Because of this, graphene is an attractive nanomaterial that has the potential to improve the performance of box-type solar cookers, which is the novelty of this research work.

Feasibility of optimum energy use and cost analyses by applying artificial intelligence and genetic optimization methods in geothermal and solar energy-assisted multigeneration systems

This study evaluates the potential for optimizing energy utilization and cost analysis in geothermal and solar energy-supported multigeneration systems using artificial intelligence (AI) and genetic algorithm (GA) optimization methods. Integrating renewable energy sources aims to promote sustainable energy solutions focusing on efficiency and cost-effectiveness. A cogeneration system that leverages geothermal and solar energy for electricity generation and space cooling is analyzed. The model incorporates an organic Rankine cycle (ORC) for power generation and a geothermal-solar absorption cooling cycle for space cooling, developed using Artificial Neural Networks (ANN) and optimized through thermoeconomic methods. Thermodynamic and thermoeconomic analyses guide the optimization process using an ANN-based GA method. The system, with parameters such as a 130 °C geothermal source temperature, an 85 kg/s mass flow rate, and a 600 W/m2 monthly average solar radiation intensity in Afyonkarahisar, achieves overall energy and exergy efficiencies of 19.5 % and 43.5 %, respectively. Optimization via the GA method significantly improves performance, increasing net power output from 2240 kW to 2760 kW and cooling capacity from 2720 kW to 3061 kW. Additionally, the cost of electricity decreases by 12.1 %, from 0.0165 $/kWh to 0.0145 $/kWh, while the cooling cost is reduced by 41.9 %, from 0.0745 $/kWh to 0.0525 $/kWh.

Optimizing COP by RSM and MATLAB model of mini refrigerator based on thermoelectric units driven by solar photovoltaic

AbstractEnergy scarcity in the world and the pollutants resulting from excessive use of conventional energy aroused the need for sustainable alternatives that are environment friendly. A multi-use thermoelectric refrigerator powered by solar energy to obtain the lowest consumption with the highest efficiency. The designed refrigerator is based on the Peltier effect using Peltier units where a temperature difference is created between the junctions by applying a voltage difference across the junction. This study investigates the performance of a refrigerator cooling system powered by a photovoltaic (PV) system. The research aims to assess the efficiency, effectiveness, and feasibility of utilizing solar energy to drive refrigeration, particularly in off-grid or environmentally conscious applications. Through a comprehensive experimental setup and data analysis, the study examines energy consumption, cooling efficiency, and overall system performance under varying conditions. The findings contribute valuable insights into the potential of PV-powered refrigerators as sustainable cooling solutions. It relies on a control unit that measures the resulting temperature to determine the appropriate connection mode to give the highest cooling efficiency. The average solar radiation when operating for 8 h, for the different seasons of the year was 149.5, 67.5, 119.3, and 118.3 w/m2 in summer, winter, spring, and fall, respectively. The average cooling energy consumption was 107.25, 137.04, 107, and 138.08 w for temperatures (20 ± 1, 15 ± 1, 20 ± 2, and 15 ± 2) °C respectively that proof solar radiation is sufficient to produce energy for the summer of cooling temperatures up to 15 °C, while in the spring and fall it is sufficient to 20 °C. The Fast not Eco mode is the least energy consuming and the fastest cooling, it can be used for rapid cooling at a short time less than an hour. The best mode in the case of continuous operation is the case of as next Eco mode cooling temperature of 20 ± 0.1 °C. The MATLAB Simulink model was developed to reduce the design cycle and facilitate the integration of solar photovoltaic with the TEC. The optimal operating point is identified through simulation and validated through experimental analysis, the optimal COP was 71.089% by Response surface methodology (RSM).

A novel method of high-density urban block form generation based on multi-objective solar performance optimization: A case study of Nanjing

Efficiently harnessing solar radiation in high-density urban environments to optimize block forms holds significant potential for advancing urban low-carbon development. This paper introduces a novel method for generating high-density block forms based on comprehensive solar utilization. Grasshopper was used to compile an automated workflow for block form generation, solar simulation, and multi-objective optimization algorithms. Leveraging maximum solar radiation within and surrounding the block and effective photovoltaic utilization ratio are the three objectives in the multi-objective optimization process. From 60,000 generated samples, 1200 block forms were selected as the Pareto fronts. As the plot ratio of the generated blocks increases from 3 to 7, the annual mean solar radiation around the block decreases from 891.3 kWh/m2 to 863.5 kWh/m2, a reduction of only 3.1 %. When the number of blocks within the block increases from 1 to 4, the average solar radiation inside the block increases from 484.8 kWh/m2 to 516.1 kWh/m2, an increase of about 6.5 %. Additionally, as site coverage increased from 30 % to 60 %, the average solar radiation inside the block decreased from 549.2 kWh/m2 to 459.8 kWh/m2, a decrease of approximately 17 %. Notably, the photovoltaic power generation fell from 90.3 kWh/m2 to 61.2 kWh/m2, a decrease of about 32 %. The results indicate that the grid modeling method and multi-objective optimization algorithm adopted in this study can significantly improve the diversity of block morphology and achieve multiple solar performance requirements. The findings support designers in swiftly assessing building volume rationality and solar utilization potential at the early stages of urban design.

Modulating intramolecular charge transfer via π-d conjugative effect in coordination polymers toward photo-thermo-electric conversion

The prospect of harnessing sunlight to generate cost-effective heat and electricity presents a captivating opportunity to address water scarcity and electricity shortages. Photothermal materials with a broad absorption spectrum are indispensable for effectively harnessing solar energy and converting it into heat/electricity. Herein, we developed an intramolecular charge transfer strategy via conjugated effect to regulate solar absorption and photothermal conversion ability of M-DABDT (M = Fe/Co/Ni/Cu/Zn, DABDT = 2,5-diaminobenzene-1,4-dithiol), overcoming a common limitation of narrow absorption and low photothermal efficiency in traditional metal-organic assemblies. The density functional theory calculations reveal that altering transition metal ions induces the structural torsion of organic linkers, resulting in a significant change in dihedral angle from 89.96° to 2.57°. The structural change significantly facilitates the charge transfer and electron relaxation, ultimately promoting the conversion of light to heat. Under one sun irradiation, the maximum temperature of Fe-DABDT can reach approximately 92.5 ℃. More significantly, the integration of M-DABDT CPs and thermoelectric devices under normal solar irradiation results in an extraordinary open circuit voltage (238 mV) and maximum power density (364.5 μW m−2), processing a peak output voltage density of 76.9 V m−2 at 11:00 a.m. in the presence of outdoor sunlight. This strategy presents an avenue for developing metal-organic solar absorbers for photo-thermo-electric conversion systems.

Radiative cooling materials prepared by SiO2 aerogel microspheres@PVDF-HFP nanofilm for building cooling and thermal insulation

Radiative cooling is promising in meeting the current global demand for green sustainable development. However, the effective cooling of the existing radiant cooler will be limited due to the serious solar energy absorption and poor thermal insulation performance on the cold side. To addresss these issues, we propose herein a novel composite material of silicon dioxide (SiO2) aerogel microspheres combined with polyvinylidene fluoride-cohexafluoropropylene (PVDF-HFP) nanofiber membrane, in which SiO2 aerogel microspheres are firstly synthesized by sol-gel method and then incorporated into PVDF-HFP nanofiber membrane to give radiative cooling performance. As we expected, the molecular vibration characteristics of PVDF-HFP nanofiber membrane and the phonon polarization resonance of Si-O-Si bond in the transparent window can enhance the infrared emissivity of the membrane surface. In addition, the high porosity and the mesoporous structure formed by the interconnection of nano-network skeletons of SiO2 aerogel microspheres determine its excellent thermal insulation performance. The as-prepared material displays that the average solar reflectance of the composite membrane is 96.07 % and the average infrared emissivity of the atmospheric window is 94.95 %. Notably, when the average solar radiation intensity is 885.56 W•m−2, the passive radiative cooling temperature during the day can reach 11.2 °C. Furthermore, this material has excellent self-cleaning and thermal insulation performance, making it a potential radiant cooling candidate in many fields.

Durable hybrid metamaterial with hierarchically porous structure for efficient passive daytime radiative cooling

Passive daytime radiative cooling, which strongly emits heat while minimally absorbing sunlight, constitutes a promising strategy to address the energy density mismatch between solar irradiance and the low infrared radiation flux from material surfaces. However, nanoscale-precision manufacturing and the need for additional metal backing often result in low efficiency and limited applicability. Here, we present a durable hybrid metamaterial (DHM) comprising a randomly distributed inorganic dielectric particle–polymer composite with a hierarchically porous structure created via a simple phase separation method. Despite the absence of a metal backing, the DHM exhibits a broadband, high mid-infrared emissivity of 98.2 % and a high solar reflectivity of 98.0 %, enabling it to strongly radiate heat and scatter sunlight. Outdoor testing demonstrates that the DHM achieves an average cooling temperature of 9.0 °C under an average solar irradiance of 853.4 W·m−2, comparable to recently reported radiative coolers. The high electronegativity of C–F bonds in polyvinylidene fluoride–hexafluoropropylene (PVDF–HFP) and the high thermal and chemical stability of zirconium dioxide microparticles (ZrO2 MPs) endow the DHM with excellent environment durability. Moreover, the DHM provides effective and passive protection for ice and snow under sunlight exposure. Considering its outstanding cooling performance, environmental stability, and scalability, the DHM holds great promise for widespread applications in building and vehicle cooling, as well as glacier preservation efforts.

How to cool a warming world? – The potential of photovoltaic green cooling with natural refrigerants in sunbelt countries

The study investigates the economic feasibility of photovoltaic-powered air-conditioning (AC) systems in thirteen different sunbelt countries. Two different technical solutions have been analysed: (i) hybrid (partially PV powered, grid-connected) and (ii) off-grid (fully PV powered, no grid connection). These two solutions have been studied for three different locations in each country, namely minimum, average and maximum annual global solar irradiation on the horizontal. Lastly, each solution and location has been examined for application in the residential and commercial sector. All solar-based air-conditioning scenarios use high efficiency AC appliances with R290 as refrigerant (Global Warming Potential – GWP of 1) and have been compared against a base-case scenario using AC units with moderate efficiency AC appliances with conventional R410a refrigerant (GWP of 2088) and 100 % grid electricity supply. The scope of the study is to identify the economic potential of solar PV cooling technologies. Levelized Cost of Electricity (LCOE) and Net Present Value (NPV) have been calculated for each scenario as part of the comparative analysis. It was found that hybrid photovoltaic-based air-conditioning for a residential house has a financial advantage over grid-based air-conditioning in eleven out of thirteen countries investigated. Exceptions are Ghana and Vietnam. Off-grid photovoltaic-based air-conditioning for residential houses is only economically feasible in five out of thirteen countries, namely Costa Rica, Iran, Grenada, Philippines and Thailand. Hybrid photovoltaic-based air-conditioning for a small commercial building has a financial advantage over grid-based air-conditioning in ten of thirteen countries, except in Colombia, Ghana and Iran. Off-grid photovoltaic-based air-conditioning for a small commercial building is only feasible in China, Grenada, Kenya and Philippines.

Measuring solar radiation and spatio-temporal distribution in different street network direction through solar trajectories and street view images

Under the dual pressures of rapid urbanization and global warming, the management of solar radiation has become an urgent issue to address. In this context, the potential regulatory role of urban street networks on solar radiation has garnered widespread attention. However, existing research lacks an understanding of the impact of street direction. By utilising street view data and solar trajectory simulation technology, it becomes possible to facilitate the revelation of spatiotemporal differences in solar radiation across streets with different direction. The results show that solar radiation is generally lower on north–south streets than on east–west streets. In terms of spatial differences, the average solar radiation in the fifth ring of Beijing is 25.38% higher than that in the second ring. Temporally, the average solar radiation in August, the highest month, is 15.98% greater than in October, the lowest month. Additionally, solar radiation on east–west street direction shows more intense variations in summer. A periodic variation in solar radiation was also discovered in relation to street angles, with different frequencies and amplitudes at 30° and 180°. This study is the first to focus on the directional attributes of roads at an urban scale. By utilising 100,000 street view images, it calculates and analyses the spatiotemporal distribution of solar radiation in Beijing during summer across different direction. The findings provide new insights into the relationship between the distribution of solar radiation and the morphology of urban roads.

دراسة التأثير الحراري لعملية تجفيف الطماطم باستخدام نظام الطاقة الشمسي

This study developed a hybrid solar greenhouse dryer (lean-to) incorporated with a solar collector and photovoltaic (PV) system for smallholder processors of tomatoes and evaluated the thermal performance of forced convection mixed-mode solar dryer with two pretreatments of fresh tomatoes (halves and slices) with salt and sugar. Tomatoes dipped in a 40% sucrose solution for 72 hours before drying exhibited a greater initial drying rate than those treated with salt. The hourly average incident solar radiation without a reflector was 673.8 (±214.2) W/m2 outside and 754.6 (±284.5) W/m2 inside the lean-to solar dehydrator during operation. The incident solar radiation in the collector ranged from 390.3 to 1156.0 W/m2, indicating higher levels at the tilt angle. The hourly average air temperatures outside and inside the solar dehydrator and solar collector during the experiment, respectively, were 30.7 (±2.3), 52.7 (±10.1), and 30.7 (±2.3), 79.7 (±26.9)°C for the salt treatment and 31.0 (±2.0), 55.1 (±15.3), and 31.0 (±2.0), 84.8 (±28.0)°C for the sugar treatment. Thus, the solar dehydrator and the solar collector raised the dehydrating air temperatures over the outside for the salt and sugar treatment by an average of 22.0, 49.0, 24.1, and 53.8ºC, respectively. The average hourly air-relative humidity inside the solar dehydrator was 33.5%, while outside was 47.2%. The pretreated tomatoes had an initial moisture content of 93.1% (w.b). The solar dehydrator's thermal efficiency was 72.21%, and its drying efficiency was 56.48%. Consequently, solar energy contributed 84.28 and 71.18% of the generated heating power. The solar dehydrator lost 15.72 and 28.82% of its remaining solar energy due to exhausted air. The solar dehydrator had a daily average energy of 59.375 kWh, and the heating power was 47.473 kWh during the experimental period (29 h).

Examining effects of air pollution on photovoltaic systems via interpretable random forest model

Renewable energy plays a vital role in power generation and solar photovoltaic systems due to resource availability throughout the year. This work aims to investigate the impact of air pollutants and meteorological parameters on the performance of the photovoltaic systems locally, taking into consideration the advantages of the photovoltaic power potential of the SW part of Romania, where Craiova is located (average solar radiation intensity >1350 kWh/m2/year). This study is based on a one-year dataset provided by a sensor that monitors particulate matter concentrations, volatile organic compounds, dioxide of carbon, ozone, noise, formaldehyde and three climate parameters (temperature, pressure, and relative humidity). The research methodology applies an innovative interpretable random forest model emphasising the implications of air pollution for photovoltaic systems. The proposed machine learning model was trained to predict the particulate matter level in air based on the basic environmental variable measurements. The study presents six random forest models of varying complexity, which reach the accuracy of classification for the selected problem up to 99 %, and applies the Shapley Additive Explanations technique to interpret the decision-making model. The observation regarding the highest concentration of particulate matter occurring during cold months, which typically do not align with peak solar irradiance, underscores the importance of considering various environmental factors in solar energy planning. With its practical implications, this insight offers decision-makers valuable information about the feasibility of optimising solar energy generation despite seasonal variations in air pollution levels, directly addressing their needs and concerns.

The Nigeria climate zones: Variability, trends and analysis from era-interim data (2010-2015)

This study analyses diurnal weather patterns in the lower atmosphere across four climate domains in Nigeria from Era-Interim data for synoptic hours of 0000, 0600, 1200 and 1800 hours from 2010-2015. The climate domain includes: Port Harcourt (tropical maritime), Enugu (bi-modal tropical continental), Jos (montane), Kano (mono-modal tropical continental) and Maiduguri (semi-arid). Findings revealed that air temperature across the areas indicate strong latitudinal positions with drier and hotter weather pattern northwards. Average air temperature across diurnal hours were 23.2-26oC, 23-29oC, 26-32oC, 26-34oC and 26.6-34 oC for Port Harcourt, Enugu, Jos, Kano and Maiduguri. Average solar radiation peaked at 1200 noon with values 508 W/m2, 639 W/m2, 830 W/m2, 905 W/m2, 832 W/m2 for the areas. Average wind speed increases northwards, i.e. 0.9-1.3m/s, 2.0-2.5m/s, 2.1-2.5m/s, 2.4-3.0m/s and 2.9-3.5m/s respectively. The wind variation is due to the surface characteristics across the areas. Southwesterly winds dominated coastal zone while southeasterly/northeasterly winds dominated the arid zone except during periods of peak rainy season. Average cloud cover for the coastal and northern domains in oktas was: 6-7 and 2-4. Relative humidity shows that prevailing atmospheric conditions at any given time are stronger at the areas close to the sources of influence and the position of Intertropical discontinuity (ITD). Humidity values were: 67-93% and 31-71% for coastal and northern domains. Rainfall amount reduces northwards i.e. 200-46 mm. Rainfall pattern is significantly influenced by the air masses source regions. These regions include closeness to massive water bodies, proximity to Sahara Desert and effects of mountainous barriers.

Solar global irradiance from actinometric degree data for Filaret Observatory (Bucharest), 1892–1903

Long-term series of solar irradiation measured at ground level are not available in the old times. However, long-term series of actinometric degree data obtained by using the Arago-Davy instrument have been recorded in the second half of the 19th century in several locations of the world. We have developed recently a method to estimate global solar irradiance on horizontal surface from actinometric degree data (doi.org/10.1007/s00704-023-04485-2). This opens a way of finding proxy information about the incident solar irradiance on various areas of the globe before the 20th century. Hourly actinometric degree data for the years 1892–1903 are available at the Filaret Observatory (Bucharest, Romania, South-Eastern Europe). The observed series have a systematic decreasing tendency, which has been removed by using a correction procedure. The proposed method is used here to evaluate solar global irradiance at Filaret Observatory. Solar irradiance data provided by the Twentieth Century Reanalysis Project version 3 (20CRv3) are used as a reference. The expected hourly and daily average solar irradiance values show reasonable qualitative consistency with the 20CRv3 data. This consistency is notably stronger during the warmer months from April to September. Much better agreement is found for the monthly averaged solar global irradiance values. At this level, the proposed method and the procedure of the 20CRv3 project seem to validate each other.

Full analysis and deep learning optimization of a sustainable and eco-friendly power plant to generate green hydrogen and electricity; A zero-carbon approach

Among alternative energy sources for fossil fuels, hydrogen has emerged as a promising candidate; however, its production methods, reliant on fossil fuels, constrain its widespread adoption as a sustainable energy source. To transcend this limitation, researchers have proposed the concept of green hydrogen production, leveraging renewable energy sources, as a viable solution. This study presents a comprehensive techno-economic analysis that seeks to evaluate the feasibility of establishing a multi-generation green power plant in Iran. Extensive climate data from diverse locations across Iran were collected to determine the most influential design parameters. A mathematical model was developed to simulate the entire system, and an innovative neural network algorithm was employed to optimize the objective functions, given the substantial computational time required for the optimization process. The results of the optimization revealed Qeshm island as the optimal location for the green power plant, considering its favorable annual average temperature, wind speed, and solar radiation intensity. Remarkably, the proposed green power plant boasts a robust power generation capacity of 10.1 MW, enabling the production of 250 tons of hydrogen per year, exhibiting a 10 % improvement in exergy efficiency, and a 6 % reduction in LCOE, in comparison to similar studies. Furthermore, it exhibits an impressive total exergy efficiency of 41.6 %, resulting in a substantial annual income of $3.9 million and achieving a commendable payback period of 1.8 years.

VALORIZATION OF ONION AND TOMATO THROUGH SOLAR DRYING: CASE OF THE SHELL SOLAR DRYER

One of the most widely grown vegetable crops in Burkina Faso is onion and tomato. Solar drying is crucial for the conservation of these products. One of the most accessible solar dryers is the shell solar dryer, which allows these products to be dried hygienically. We were able to obtain some results from the experiment carried out over three typical days with a solar dryer which shelled 1116 g of onion and 695 g of tomato cut and distributed on the three racks of the dryer. We observed a total water loss of 456 g for the onion and 257 g for the tomato from the first to the third day of the experiment. The shell solar dryer has an efficiency of 29.88% with an inlet temperature of 33°C, an outlet temperature of 76°C and an air mass flow rate of 0.004 kg/s. The average solar irradiation is 579 W/m 2.

Design and development of solar parabolic concentrator, closed-loop pressurized hot water for a household baking system – For the case of injera baking in Ethiopia

A laboratory setup with two axis of manual sun-tracking was designed and built. To get the predicted values for a solar injera stove, a 20-min heating time to prepare it for baking, 3.1 kWh power in the first hour, and 5.8 kWh (with only an 87 percent increase) in the second hour were acquired to bake 9 and 28 injera using electric injera stove, respectively. The temperature distribution on the clay surface was the range of 180 °C–220 °C. Solar injera baking stove was designed and built using the average energy required to bake one injera from an electrical injera stove. The laboratory setup was put to the test, temperatures at the receiver's surface ranging from 315 to 318 °C and an average solar radiation of 1000 W/m2 was obtained on the first test. The injera stove inlet reached a maximum temperature of 180.92 °C with a pressure of 14.5 bars during a pressurized hot water production and circulation test (load test). The surface temperature of the solar injera stove clay plate reached a maximum of 62.69 °C. Temperature of more than 60 °C was maintained on the surface of the solar injera stove plate for nearly 2 h.

Climate change impacts on the extreme power shortage events of wind-solar supply systems worldwide during 1980–2022

Economic productivity depends on reliable access to electricity, but the extreme shortage events of variable wind-solar systems may be strongly affected by climate change. Here, hourly reanalysis climatological data are leveraged to examine historical trends in defined extreme shortage events worldwide. We find uptrends in extreme shortage events regardless of their frequency, duration, and intensity since 1980. For instance, duration of extreme low-reliability events worldwide has increased by 4.1 hours (0.392 hours per year on average) between 1980–2000 and 2001–2022. However, such ascending trends are unevenly distributed worldwide, with a greater variability in low- and middle-latitude developing countries. This uptrend in extreme shortage events is driven by extremely low wind speed and solar radiation, particularly compound wind and solar drought, which however are strongly disproportionated. Only average 12.5% change in compound extremely low wind speed and solar radiation events may give rise to over 30% variability in extreme shortage events, despite a mere average 1.0% change in average wind speed and solar radiation. Our findings underline that wind-solar systems will probably suffer from weakened power security if such uptrends persist in a warmer future.