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Individuals are easily threatened by heat stress or hypothermia in outdoor environments. Therefore, there is a pressing necessity for thermal regulation materials capable of adapting to temperature shocks. Herein, an aerogel‐functionalized textile as a passive thermal regulator (AT‐PTR) is designed and demonstrated, comprising a heating side composed of carbon nanotube‐modified cotton fabric and a cooling side built of silica aerogel‐functionalized poly(vinylidene‐co‐hexafluoropropene) P(VdF‐HFP) nanofibers. The AT‐PTR demonstrates exceptional solar absorption on the heating side, achieving a warming performance of 23.2 °C in cold winter. On the cooling side, its high solar reflectance and infrared emissivity facilitate a sub‐ambient cooling effect of 12.7 °C during hot summer. Moreover, outdoor field tests of the AT‐PTR conducted across various regions and seasons demonstrate an all‐seasonal outdoor human thermal management capability. Additionally, the AT‐PTR exhibits outstanding wind‐proof and moisture permeability, and heat flow can be simply attained by flipping the AT‐PTR, ensuring sustained thermal comfort for individuals across various environments. [ABSTRACT FROM AUTHOR]

Technologies regarding solar heating, ventilation and air-conditioning (S-HVAC) are aimed at making modern 3D numerical forms that address the Sutterby flow ternary nanofluids circulating onward the convective heating and extendable seats. Heat transport includes joule heating, heat source or sink along with thermal radiation. Using fitting modifications, mathematically conveyed partial differential equations of energy, fixation and strength may decrease into ordinary differential equations (ODEs). They determine ODEs beyond dimension, and for this, the mathematical process is utilized. Copper–silver–aluminum alloys/sodium alginate (Cu–Ag–AA7075/C6H9NaO7) was used to address the behavior of this research work. The natural attributes, for example, heat movement and surface drag coefficients, are numerically prepared and shown in figures and tables when there is an alteration in distant factors. The field of temperature was raised to develop the Biot number. This heat transport rate was hiked to 34.0839% although the shear stress rate was hiked to 32.8043% in the single nanoparticle case compared to the triple nanoparticle case. To validate the analysis, a comparison between the presented and existing is reported under certain assumptions on the flow parameters. It is found that the results are reliable and in line with the existing ones. [ABSTRACT FROM AUTHOR]

The objective of this article is to examine potential techniques for suppressing solar heat flow on the optical antenna of a laser communication sensor. Firstly, the characteristics of the geosynchronous Earth orbit's (GEO) space radiation environment are analysed, and a combined passive and active thermal control solution is proposed. Secondly, the temperature distribution of the lasercom sensor under extreme operating conditions is simulated utilising IDEAS-TMG (6.8 NX Series) software, which employs Monte Carlo and radiative heat transfer numerical calculation methods. Finally, a strategy for avoiding direct sunlight around midnight is proposed. The simulation results demonstrated that the thermal control solution and solar avoidance strategy proposed in this paper achieved long-term fine-stable control of the temperature field of the optical antenna, which met the thermal permissible communication hours per daily orbit cycle in excess of 14 h per day. [ABSTRACT FROM AUTHOR]

Water is the secret of life. People demand more and more water. Solar stills generate distilled water. The present project involved designing and evaluating a heat exchanger-connected solar collector and solar still system. The effects of nanofluids on solar collector performance and solar still productivity were studied. Hybrid and mono ZnO/WO3- water nanofluids have been produced in two steps. Individual and mixed nanofluids have a volume concentration of 0.035%. Four hybrid nanofluids with varying ZnO and WO3 concentrations were examined. Nanofluid stability has been established. The thermal conductivity of nanofluids increased by 5.18–24.8%. The thermal optical efficiency of the solar collector was 0.708, with energy removal parameters of 34.888. The heat removal factor was raised to 0.8 for mono ZnO nanofluid. At a concentration of 0.035%, ZnO/water nanofluid can produce 3.14 kg of distilled water daily. The solar still's total efficiency, including pump consumption, was 39.9% for mono ZnO and 36.4% for WO3. The highest efficiency received for hybrid ZnO + WO3 nanofluids were 37.6%, 37.9%, 38.6%, and 39.2% for ZnO 0.01% + WO3 0.025%, 0.015% + WO3 0.022%, 0.025% + WO3 0.015%, and 0.025% + WO3 0.01%, respectively. As the ZnO percentage rose in hybrid ZnO + WO3 nanofluids, energy absorption, thermal conductivity, solar still productivity, and efficiency were promoted. [ABSTRACT FROM AUTHOR]

Thermal energy-driven adsorption refrigeration systems are potential alternatives to the vapour compression refrigeration system. Using solar or waste heat thermal compressors over electrical compressors diminishes fossil fuel-based energy expenditure and its adverse effects on the environment. The solar thermal energy system's cost is highly dependent on the system's maximum temperature-generating capacity. The present work focuses on the experimental investigation of the adsorption thermal compressor performance by supplying source heat at different temperatures and determining the optimum desorption temperature and the supply heat cycle time resulting in the best performance. The adsorbent–adsorbate pair considered for the study is activated charcoal extra pure powder—R134a. The compressor is supplied with hot water at different temperatures, and the variation in performance parameters such as desorption pressure, desorbed mass change and average temperature is analysed. A novel index, i.e. rate of pressure change with respect to temperature (dp/dT), is introduced to evaluate the optimum desorption temperature with respect to different supply heat cycle times. The best performance of the adsorption thermal compressor is observed in the range of 50–60 °C, and the corresponding pressure change recorded is equal to 1.04 bar in 120 s. The obtained optimum temperature and pressure range can limit the thermal energy losses and increase the desorbed mass flow rate, thereby enhancing the entire system performance. The findings can be considered in design and development of an adsorption refrigeration system driven by renewable source heat or waste heat. [ABSTRACT FROM AUTHOR]

The growing need for industrial development, limited availability of non-renewable energy resources, minimizing energy consumption, and ecosystem concerns has prompted researchers to explore the practical applications of two-phase nanofluid materials processing and electromagnetic energy emitted via the sun. Therefore, using two-phase nanofluids in solar thermal technology systems can enhance system performance by improving heat absorption and transfer efficiency. Owing to its usage, this study examines the magnetized two-phase nanofluid flow on a two-dimensional laminar mixed convective boundary layer with the impact of multiple slips. The flow contains an electrically conducting non-Newtonian nanofluid over a deformable (stretching/shrinking) sheet with a solar radiation effect. Also, the study utilizes a nonlinear Roseland diffusion flux approximation to incorporate the solar radiation effect, which is valid for nanofluid media with high optical density. This work utilizes similarity variables to simplify the partial derivative model into ordinary differential equations. These equations are then solved using the wavelets and Chebyshev wavelets scheme with the help of MATHEMATICA 11.3 software. According to the findings, the nanoparticle volume fraction is increased for high electrical conductivity (M = 2) and decreased for the electrically non-conducting case (M = 0). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Solar dryers are a convenient option for drying fruits and vegetables, but they largely depend on climatic conditions. Climate dependency makes them vulnerable to dry products and maintain the quality of the products accurately. To mitigate this problem, an electric auxiliary heating system (AHS) was designed, constructed, and tested for a solar dryer in Bangladesh. The developed system had three parts: an auxiliary heating unit, an air duct, and hot air convection pipes. The performance testing of the AHS was done in three experimental trials. The average air velocity from the auxiliary heating unit was found to be between 3.57 and 3.80 m s−1. Trial runs showed a maximum drying temperature of 66.97°C, while the average value remained between 35.10 and 43.26°C. During the off‐sunshine hours, the AHS rose the average temperature by 1.00–12.84°C above ambient and continued the drying operation. Overall, the solar dryer with AHS saved 30%–36% sunshine hours than open sun drying, and its efficiency was estimated as 14.55%–21.9%. Regression analysis showed that the Page and Modified Page models were suitable for predicting the drying kinetics of cabbage samples. Through the results of the study, the developed AHS showed potential for significantly improving the solar drying process. It could be an effective measure for establishing a weather‐independent drying solution to reduce the postharvest losses of perishable agro‐products. Further improvements to the auxiliary heating unit, implying an Internet of Things (IoT)‐based control system will facilitate an improved and user‐convenient drying operation. Practical Applications: Postharvest losses are prevalent for perishable agricultural products (fruits and vegetables) in Bangladesh and are considered a prime reason for the inhabitants to consume a less nutritious diet than recommended. An appropriate dry chain technology that is affordable, weather‐independent, continuous, and fast in operation could be the optimal solution to this problem. Numerous types of solar hybrid dryers with different additional heating sources (electricity, biomass, LPG, etc.) have been investigated around the world. However, the extent of these research endeavors is very limited in Bangladesh. The study was thus conducted to develop a novel auxiliary heating system for a solar dryer in Bangladesh and check its technical viability. Our results indicate that an electric auxiliary heating system can be an efficient option for drying fruits and vegetables irrespective of the weather and can substantially reduce postharvest losses in Bangladesh. [ABSTRACT FROM AUTHOR]

Oceanic oil spills exert enduring adverse effects on marine ecosystems and human health. In contrast to conventional cleaning methods, advanced oil sorbents present a promising technology characterized by low cost, reduced environmental impact, and exceptional hydrophobicity and oleophilic properties for efficient oil removal from seawater. Despite these advantages, the efficacy of sorbents is hindered by highly viscous oil, impeding the oil/water separation process. To overcome this limitation, solar‐driven sorbents incorporating semiconductor materials are innovatively developed, leveraging increased temperatures to enhance crude oil absorption by reducing viscosity. Herein, a comprehensive review specifically focuses on various semiconductor‐functionalized sorbents for oil spill remediation, elucidating oil weathering and traditional cleaning methods to underscore the complexities and challenges in oil cleaning processes. An in‐depth discussion about the cleaning mechanisms of sorbents and the photothermal conversion processes facilitated by semiconductors is also provided. Additionally, it explores three coupling strategies—Joule heating and solar heating, photothermal effect, and magnetic effect, as well as photothermal and photocatalysis—that offer significant advancements in oil cleanup efficiency. Concluding with forward‐looking insights, the challenges and perspectives for the next generation of ocean oil spill removal technologies are proposed at the end. [ABSTRACT FROM AUTHOR]

Antarctic sea ice extent has been persistently low since late 2016, possibly owing to changes in atmospheric and oceanic conditions. However, the relative contributions of the ocean, the atmosphere and the underlying mechanisms by which they have affected sea ice remain uncertain. To investigate possible causes for this sea‐ice decrease, we establish a seasonal timeline of sea ice changes following 2016, using remote sensing observations. Anomalies in the timing of sea ice retreat and advance are examined along with their spatial and interannual relations with various indicators of seasonal sea ice and oceanic changes. They include anomalies in winter ice thickness, spring ice removal rate due to ice melt and transport, and summer sea surface temperature. We find that the ice season has shortened at an unprecedented rate and magnitude, due to earlier retreat and later advance. We attribute this shortening to a winter ice thinning, in line with ice‐albedo feedback processes, with ice transport playing a smaller role. Reduced ice thickness has accelerated spring ice area removal as thinner sea ice requires less time to melt. The consequent earlier sea ice retreat has in turn increased ocean solar heat uptake in summer, ultimately delaying sea ice advance. We speculate that the observed winter sea ice thinning is consistent with previous evidence of subsurface warming of the Southern Ocean. Plain Language Summary: Following 2016, the Antarctic sea ice cover has been persistently low. To understand why, we retrace the seasonal timeline of sea ice and oceanic changes, using satellite observations. We find that the sea ice season has been significantly shorter following 2016, due to a later start and an earlier end. This shortening is likely caused by thinner sea ice in winter, accelerating sea ice melt in spring and causing sea ice to disappear earlier. In turn, this has caused the ice‐free ocean to absorb more solar heat in summer, and to take longer to cool down in the fall, ultimately delaying the ice season onset. Warmer waters beneath the Southern Ocean's surface, as evidenced by previous studies, could be a plausible cause of the observed thinning, by increasing the heat supply to sea ice. Key Points: The Antarctic sea ice season duration has undergone an unprecedented shortening since 2016The changes include thinner ice, faster melt, earlier retreat, larger ocean heat uptake, later advance, in line with the ice‐albedo feedbackThe near‐circumpolar ice thinning suggests a possible increase in sensible heat supply by the ocean [ABSTRACT FROM AUTHOR]

We show the performance of solar heating by coupling a Solar Water Heating System (SWHS) with an Absorption Heat Transformer (AHT) for annual continuous water heating. Solar Fraction (SF), Solar Heat Gain (SHG), and Auxiliary Heat (Qaux) were meticulously assessed for three Mexican cities located in the most characteristic climates (Saltillo, Toluca, and Tapachula). This rigorous assessment process ensures the reliability and accuracy of our findings. The potential reduction in net solar collector area (Ac) and storage tank volume (Vt) can be seen by comparing its annual performance to that of a conventional SWHS. Both configurations were designed to deliver the same hot water amount (0.019 kg/s, 1693.4 L/day, heating from 15.8 to 94.4 °C) and simulated using TRNSYS software version 16.01 concerning combinational systems. The results showed that SWHS-AHT achieved superior performance in solar water heating, achieving a higher SF (up to 99.6%) and SHG (up to 1352 kWh/m2-year) compared to the conventional SWHS. On the other hand, the SWHS-AHT achieved similar performance to a conventional SWHS with up to 60% less Ac. For instance, in Tapachula, a SWHS-AHT with an Ac of 150 m2 and a Vt of 18 m3 matched the performance of a SWHS with an Ac of 375 m2 and a Vt of 15 m3. Notably, both systems required the same Qaux. Thus, the Qaux requirement shows that SWHS-AHT is promising for industrial applications in Mexico, offering improved performance and a reduced footprint. [ABSTRACT FROM AUTHOR]

The global energy transition requires efficient seasonal energy storage systems (SESSs) to manage fluctuations in renewable energy supply and demand. This review focuses on advancements in SESSs, particularly their integration into solar district heating systems, highlighting their role in reducing greenhouse gas emissions and enhancing energy efficiency. Tanks are the most suitable solutions for seasonal storage, as they can be implemented regardless of location for volumes up to 100,000 m3. However, pits are the most optimal solutions in terms of cost and size, as they can be constructed for volumes up to 200,000 m3. This review analyses key performance indicators such as energy efficiency, cost-effectiveness, and environmental impact, drawing on case studies from countries like Denmark and Germany. Notable findings include Denmark's Silkeborg system, which supplies 22,000 households and reduces CO2 emissions by 15,000 tons annually. Challenges such as high initial costs and system maintenance remain, but coupling SESSs with heat pumps enhances thermal stratification within SESSs. This approach can reduce the annual cost by up to 9% and the purchase cost of energy by 23%. Future research should focus on innovative materials, system design optimization, and supportive policies to enhance adoption. In conclusion, advancing SESS technologies and integrating them into renewable energy systems is necessary for achieving sustainable energy solutions and mitigating climate change impacts. [ABSTRACT FROM AUTHOR]

The diurnal cycle of dust aerosols on Mars is studied by analyzing lidar observations at the Phoenix landing site under cloud‐ and fog‐free conditions and in the absence of elevated, long‐range transported dust layers. There is a pronounced diurnal cycle in the dust‐layer height with minimum heights of 4–6 km occurring between 11:00 and 17:00 local time. The ratio of the aerosol optical depth (AOD) within the lowermost 2 km to the total AOD reaches peak values at the same time. This can be explained by local dust emissions driven by the diurnal cycle of heating and cooling in the boundary layer. Analysis of wind and pressure measurements show that the gustiness of surface winds and the frequency of convective vortices undergo diurnal variations resembling those of AOD, indicating that these processes are the main drivers for local dust emissions. Plain Language Summary: Dust particles suspended in air are important for the radiative energy budget of Mars. By interacting with solar radiation, these aerosols impact the temperature, dynamics, and composition of the atmosphere, as well as the surface temperature of Mars. Dust aerosols are produced by wind‐lifting processes ranging from small‐scale eddies to planetary‐scale dust storms, resulting in spatially and temporally varying concentrations. Here the focus is on the diurnal cycle of dust emissions as observed by the Phoenix lander. By jointly analyzing light‐scattering observations by a lidar instrument and measurements of wind speed and air pressure, one can correlate the concentration of aerosols in air in proximity to the ground to meteorological processes. The results reveal distinct maxima in aerosol loads, the intensity of wind gusts, and the frequency of dust devils around local noon and early afternoon, and corresponding minima around midnight. This indicates that gustiness and dust devils, both fueled by solar heating during the day, are among the main causes for local dust emissions. During daytime the aerosols are concentrated at altitudes of 4–6 km. This can provide us with an indication for the degree of vertical mixing in the planetary boundary layer of Mars. Key Points: Diurnal variation of local dust emissions, wind gustiness, and convective vortices are analyzed for the entire Phoenix missionPeak values are observed in early afternoon, indicating that gustiness and convective vortices are main drivers for local dust emissionsTypical dust‐layer heights in early afternoon are 4–6 km, consistent with typical boundary‐layer heights [ABSTRACT FROM AUTHOR]

In the presented study, the focus is on the exergy efficiency of a textile factory that has the potential to optimize itself using solar energy and waste heat. Two distinct scenarios are considered in this study. In Scenario 1 (S-1), the whole system components operate solely for hydrogen production, while in Scenario 2 (S-2), the whole system components are utilized for both electricity, heat water and hydrogen production. For the harnessing waste heat, a 25 kW capacity Organic Rankine Cycle (ORC) system, 20 evacuated tube solar collectors (ETSC) for solar energy utilization, and a water electrolyzer for hydrogen production are employed. As a result of the thermodynamic analysis of the whole system, the energy and exergy efficiency is calculated as 5.17 %, 2.63% and 39.32%, 21.74%, respectively, according to the S-1 and S-2 scenarios. Furthermore, considering S-1 and S-2 conditions, hydrogen production amounts to 5197 kg/annual and 2209 kg/annual, respectively. • The highest hydrogen production amount is calculated as 5197 kg/annual, depending on S-1 Scenario operating conditions. • The highest energy efficiency is calculated as 39.32% based on S-2 Scenario operating conditions. • The highest exergy efficiency is calculated as 21.74% based on S-2 Scenario operating conditions. [ABSTRACT FROM AUTHOR]

Chromospheric condensations (CCs) are a prominent feature of flare footpoint heating in the solar flare standard model, yet their timescales and velocities are not well understood. Fisher derived several important analytical relationships, which have rarely been examined with modern spectral observations. The Interface Region Imaging Spectrograph (IRIS) provides a wealth of flare data with a high enough cadence to sufficiently capture CC evolution. We analyzed Doppler shifts in Mg ii 2791 and Fe ii 2814 from a sample of flare footpoint pixels observed by IRIS to compare with Fisher's analytics and recent flare models. We found a detection lifetime of 1 minute occurs in 50% of the sample, with Mg ii showing several pixels with longer values and Fe ii almost categorically shorter, and both growing with the maximum velocity, v max. The shifts' half-life is commonly <40 s and is inversely related to v max, indicating that the first half of the CC evolution has more efficient kinetic energy loss. The lifetime's wide range and growth with v max indicate that the footpoint atmospherics and heating scenarios can vary more widely than first postulated in Fisher. Around 90% of the sample had observable acceleration periods, lasting an average of 38 and 32 s for Mg ii and Fe ii, respectively. These acceleration periods, as well as serving as flare model diagnostics themselves, could potentially be used to calculate other model diagnostics such as the initially accelerated mass. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) smart windows are an elegant alternative to dusty curtains, blinds, and traditional dimming devices. The EC energy storage smart windows and displays received remarkable attention in the optoelectronic industry as they hold promise for high energy efficiency, low power consumption, reversibility, and swift response to stimuli. However, achieving these properties remains challenging. Moreover, most EC molecules do not exhibit electrofluorochromism, which is highly essential for smart displays because its EC property can modulate the solar heat entering the building, and its electrofluorochromic (EFC) aspects can create lighting during the night. In this work, a structure‐property relationship is utilized to develop new electrochromes that can store the injected charge, and these molecules indeed exhibit electrofluorochromism. The compounds are synthesized from tetrabenzofluorene with two aromatic acceptor units, and avoids the use of widely studied heterocycles and amine derivatives. The electrochromes switches from yellow to dark hue in solution, solid, and gel state. The compounds display exceptional electrochemical stability and reversibility in 1000 cycles and capacity retention of 93–100 % in 300 charging‐discharging cycles. The proof‐of‐concept device fabrication of the self‐dimming EC smart window presented here demonstrates that it can furnish visual comfort, modulate transmitted light and glare, and reduce energy usage. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the impact of solar radiation intensity on the performance of direct-expansion solar PVT heat pump systems. To this end, an experimental setup was constructed for direct-expansion photovoltaic (PVT) solar heat pump water heating systems and photovoltaic (PV) power generation systems. The system performance and main parameters were analyzed and discussed under different solar radiation intensities. The winter experiments in southern China revealed that the exhaust temperature of the heat pump unit varied considerably under clear conditions, while the back temperature remained stable, fluctuating between approximately −13.5 °C and 24 °C. In contrast, the power generation of PVT panels increased with the increase in radiation intensity, from 78.33 W to 122.68 W, for an increase of 56.6%. Furthermore, the total electricity generation of the PVT panels was higher than that of PV panels, with an increase of 8.7–8.3%. Nevertheless, discrepancies between experimental and theoretical data were observed, particularly under overcast conditions, where the back panel temperature error was pronounced. Additionally, the system exhibited enhanced stability at elevated temperatures in comparable environments, accompanied by an improvement in the system's coefficient of performance (COP) by 5.67%. [ABSTRACT FROM AUTHOR]

Linear Fresnel reflectors are a versatile solar concentration technology, suitable for a wide range of industrial processes and thermal conditioning applications. Such collectors entail a certain footprint, generating shading on the surface where they are installed. This effect is rarely quantified but may play an indirect role on the surface below. When installed on a roof, the solar radiation heats the building less. In places where the annual heating demand is higher than the cooling demand, this constitutes an asset. However, this becomes a disadvantage when the cooling demand is higher annually than the heating demand. Essentially, the reduced solar radiation allows for the growth of plants that would not grow without the shade provided by the collector. The present paper is a quantitative analysis of such shading based on the linear Fresnel reflector of the Cyprus Institute. The work was conducted using the Tonatiuh++ ray-tracing software to determine the annual radiation blocking. A total of four years of actual meteorological measurements were applied directly to the ray-tracing model. [ABSTRACT FROM AUTHOR]

This paper concerns an economic and exergetic efficiency analysis of a plate heat exchanger placed in a solar installation with TiO2:SiO2/DI:EG nanofluid. This device separates the primary circuit—with the solar fluid—and the secondary circuit—in which domestic hot water flows (DHW). The solar fluid is TiO2:SiO2 nanofluid with a concentration in the range of 0.5–1.5%vol. and T = 60 °C. Its flow is maintained at a constant level of 3 dm3/min. The heat-receiving medium is domestic water with an initial temperature of 30 °C. This work records a DHW flow of V ˙ D H W , i n = 3–6(12) dm3/min. In order to calculate the exergy efficiency of the system, first, the total exergy destruction, the entropy generation number Ns, and the Bejan number Be are determined. Only for a comparable solar fluid flow, DHW V ˙ n f = V ˙ D H W 3 dm3/min, and concentrations of 0 and 0.5%vol. is there no significant improvement in the exergy efficiency. In other cases, the presence of nanoparticles significantly improves the heat transfer. The TiO2:SiO2/DI:EG nanofluid is even a 13 to 26% more effective working fluid than the traditional solar fluid; at Re = 329, the exergy efficiency is η e x e r g y = 37.29%, with a nanoparticle concentration of 0% and η e x e r g y (1.5%vol.) = 50.56%; with Re = 430, η e x e r g y (0%) = 57.03% and η e x e r g y (1.5%) = 65.9%. [ABSTRACT FROM AUTHOR]

• The article introduces a novel semi-empirical model for a TEV operating with R290. • No prior experimental work was found involving TEV operating with R290 in DX-SAHP. • The article emphasizes a careful data collection process encompassing 150 experiments. • The multiple linear regression resulted in a R² of 0.9648 with predictions not exceeding more than 15 % deviation. • The model was applied and compared with 44 experiments from the literature, resulting in a deviation of less than 15 %. The expansion device plays a crucial role in the operation of heat pumps and refrigeration systems, making its study integral to advancements in the fields of refrigeration and heating. Among various expansion devices, the Thermostatic Expansion Valve (TEV) stands out due to its rapid response time and mechanical nature, which grants it high control capacity over refrigerant superheating. In this study, was developed a semiempirical mathematical model for a TEV incorporated in a DX-SAHP utilizing R290. The research was carried out in an experimental way, conducted using a fully instrumented DX-SAHP. A series of experiments tested different operational modes for water heating, subject to varying solar radiation intensities. A uniform methodology collected operational parameters, resulting in 150 experiments. The semiempirical model creation involved combining basic equations from the literature describing TEV operation and formulating an equation using multiple linear regression based on experimentally evaluated parameters. These parameters included solar radiation incidence, inlet and outlet pressures, and superheating degree. The regression model achieved an adjustment higher than 96 %. Combining this regression with equations suggested by previous researchers, resulted in a model with an adjustment exceeding 94 %. Furthermore, this study culminated in the derivation of a generalized model primed for broad application across various heat pump configurations for water heating purposes. Notably, the model underwent rigorous validation across a separate set of experiments, reaffirming its reliability and versatility. While excelling in steady-state operations, the model's transient data analysis falls short, as intended. [ABSTRACT FROM AUTHOR]

Efficient utilization of nanofluids in shell-and-tube heat exchangers for solar thermal energy systems requires a rigorous sensitivity analysis, enabling fine-tuning design parameters to achieve optimal heat transfer performance and overall system efficiency. Previous research has primarily focused on utilizing nanofluids to enhance heat transfer in solar thermal systems, emphasizing nanoparticle selection, optimization techniques, and sensitivity analysis. The central concern addressed by this study is the development of an optimal shell-and-tube heat exchanger (STHE) configuration employing nanofluids within a solar thermal energy framework. The research uses statistical modeling to analyze the interplay between heat transfer coefficients, pressure drops, and shell dimensions in nanoscale heat exchanger construction. Utilizing computational fluid dynamics (CFD) simulations, the study investigates flow patterns and temperature distributions within the heat exchanger, considering variations in hot water flow rates, initial dimensions, cold-water flow rates, and tube geometries for optimization. The findings underscore the positive impact of increased cold-water flow rates on efficiency and total heat transfer coefficients, while longer initial dimensions result in decreased efficiency. Regarding sustainability, corrugated tubes are superior to smooth tubes, shedding light on the relationship between energy efficiency and sustainability in this context. [ABSTRACT FROM AUTHOR]

[Display omitted] To cope with the demand of more complex and variable applications, it is urgent to develop dual-mode triggered, breathable, and shape-memory wearable heaters for all-weather personal thermal management of composite phase change materials (PCMs). Herein, after high-temperature carbonization of ZnCo-MOF (metal–organic framework) nanosheet array grown in situ on flexible and breathable carbon cloth (CC) and subsequent encapsulation of polyethylene glycol (PEG), the as-prepared PEG/CC@Co/CNT (carbon nanotube) composite PCMs exhibited good breathability, mechanical strength (tensile strength of 9.15 MPa), thermal energy storage density (114.19 J/g), and shape memory due to the synergy of flexible CC skeleton and rigid PEG. More importantly, composite PCMs possessed excellent solar-thermal (93.7 %, 100 mW/cm2) and electro-thermals (94.5 %, 2.0 V) conversion and storage capacity, benefiting from the conjugation effect of high graphitized carbon/carbon heterostructure with fast electron/photon/phonon transmission and the localized surface plasmon resonance effect of Co nanoparticles. Therefore, the integration of solar heating and Joule heating into breathable composite PCMs can be accurately used for next-generation all-weather, all-season, dual-mode triggered personal thermal management, including indoor/outdoor, daytime/night, rainy/cloudy and other complex and changeable scenarios. [ABSTRACT FROM AUTHOR]

Interest in the research of renewable natural energy sources, such as solar, wind, water, and biomass, which will both protect the environment in an ecological sense and contribute to sustainable development, is increased to prevent the energy crisis that may occur in the future with the decrease in energy resources. Low‐cost and environmentally friendly nanogenerator systems are developed to generate, efficiently use, and store the energy obtained from these sources. A small portion of sunlight is used by solar heat collection and energy panel systems developed to generate heat and electricity; the remaining large part, in contrast, is used by photosynthetic organisms such as plants and algae to ensure the photosynthetic cycle. Photosynthetic energy, nanomaterials used to collect this energy, device performances, the effect of the parts in the photosynthetic cycle on device efficiency, and recent developments are discussed, and the development of photosynthetic energy is reviewed. Nanostructured materials play an active role in increasing the photosynthetic effect while converting solar energy into electrical energy by photosynthesis. Further research on developing photosynthetic nanogenerators, particularly enhancing the generation of photosynthetic electrons using nanomaterials and ensuring their more efficient transfer, is recommended. [ABSTRACT FROM AUTHOR]

Introduction: The surface expression of enhanced geothermal heat fluxes above an active hydrothermal system causes a surface thermal anomaly (ΔΌ. The thermal anomaly is expressed by the difference between the temperature within the heated zone (Th) and the temperature of non-heated surfaces (T0). Given that the resulting thermal anomaly at the surface is of extremely low magnitude (1°C-5°C at Vulcano, Italy), it is extremely sensitive to overprinting by external factors, namely, meteorological influences on surface temperature variation, such as solar heating, wind and rain. Methods: To test the sensitivity of the surface to external drivers, we installed two surface temperature measurement stations within the Vulcano's Fossa crater, one inside the thermal anomaly and one outside (separation = 50 m), with a weather station co-located with the T0 station. Time series of Th and T0 were collected for 2020, when the Vulcano Fossa hydrothermal system was at a low and stable level of activity so that external drivers would have been the main influences on Th and T0, and hence also ΔT To test for divergence from normality in terms of diurnal and seasonal variations in Th and T0, and the role of external factors in causing abnormality, we used the deep learning engine DITAN: a domain-agnostic framework to detect and interpret anomalies in time-series data. Results: During the year, DITAN found 16 cases of two types of meteorological events: intense low-pressure systems and high-intensity rainstorms (cloudbursts). Passage of 13 abnormal low-pressure systems were detected (10 between February and May, and three in December), with three abnormal rainstorm events (all in December); all three being coincident with the abnormal low pressure events. We find just two abnormalities in the time series for of Th and T0, both of which coincide with passage of abnormal low-pressure systems, and neither of which coincide with abnormal rain events. We conclude that diurnaland annual heating and cooling cycles, subject to normal meteorological inputs and at a surface above a geothermal-heated source, are immune to anomalous behaviour to the external (meteorological) variations. [ABSTRACT FROM AUTHOR]

Precipitation changes in northern China are projected to increase in the Coupled Model Inter‐comparison Project Phase 6 (CMIP6) multi‐model ensemble. However, these projections are accompanied by notable inter‐model uncertainty, and the sources of this uncertainty remain largely unexplored. By analyzing 30 CMIP6 models, this research explores the source of inter‐model uncertainty in projected precipitation change and reveals the fundamental mechanism driving uncertainty spread. Following the empirical orthogonal function of inter‐model projected precipitation change, the leading mode displays a seesaw spatial pattern between northwest and north China. This phenomenon predominantly stems from the inter‐model divergence of projected sea surface temperature (SST) warming in the North Atlantic. Further scrutinizing the ocean mixed layer heat budget, we discover that the combined effect of surface sensible heat flux, net surface shortwave radiation flux, and ocean heat transport convergence influences heat flux and SST change of North Atlantic. The multi‐model projections indicate that localized increases in solar radiation and heat convergence warm sea surface, raising SST and initiating convective motion. This convective motion subsequently transforms the 200 hPa teleconnection wave train, leading to an anti‐phase pattern over northern China. This wave pattern modulates total cloud cover percentage, influences surface upward latent heat flux, and adjusts the top of atmosphere outgoing longwave radiation, collectively resulting in the seesaw pattern. Our study underscores the pivotal role of inter‐model disparities in North Atlantic SST warming projection, which is a primary driver of precipitation uncertainty in northern China. These insights offer an essential foundation for refining and diminishing inter‐model uncertainty. Plain Language Summary: The Coupled Model Inter‐comparison Project Phase 6 multi‐model ensemble projects significant precipitation uncertainty due to differences in couplers and components of the global system model. This study identifies the discrepancies in projected North Atlantic sea surface temperature (SST) warming as the primary source of inter‐model uncertainty for projected precipitation changes in northern China. The projected SST warming amplifies heat transfer from the ocean surface to the atmosphere, intensifying upward air motion. This process alters the teleconnection wave trains at 200 hPa, propagating downstream to form an anti‐phase pattern in northern China. These upper atmospheric shifts regulate upward and subsiding motions, influence total cloud cover percentage, modify the top of atmosphere outgoing longwave radiation, and impact surface upward latent heat flux. Together, these atmospheric dynamics forge a seesaw spatial precipitation pattern in northern China. The combined effect of surface sensible heat flux, net surface shortwave radiation flux, and ocean heat transport convergence influence heat flux and SST change in the North Atlantic. Our findings elucidate the complex spread process of inter‐model uncertainty in precipitation projection, setting the stage for more precise projection in northern China. Key Points: The leading precipitation pattern exhibits a seesaw in northern China due to inter‐model differences in North Atlantic sea surface temperature (SST) warmingThe model with a higher SST warming tends to induce a strong teleconnection wave train, resulting in a more pronounced seesaw patternSurface sensible heat flux, net surface shortwave radiation flux, and ocean heat transport convergence influence heat flux and SST change [ABSTRACT FROM AUTHOR]

Global climate crises are the most significant challenges to be solved these days. As one of the technological endeavors to tackle the issue, radiative cooling is amongst the most attractive approaches for sustainable heat energy regulation, which involves maximizing solar heat reflection and thermal heat emission. These green technologies inevitably require architectural applicability, considering that building facades take a large proportion of the heat‐radiating surfaces. For mass‐production suitability and durability, radiative coolers (RCs) fabricated in a fully ceramic context are recently suggested, featuring scalable, thermally insulative, and non‐shrinking advantages. However, the visual effects are also imperative for architectural instances but are seldom accounted for. In this context, this article suggests the enhanced color‐preserving radiative cooling (ECRC) structure for practical architectural applications of glass‐infiltrated ceramic RCs. By simply blending ceramic pigment into the uppermost porous alumina layer, the ECRC structure can maintain the physical, and thermal features of all‐ceramic RC, while exhibiting color by visible reflectance adjustment. ECRCs exhibit an additional cooling performance of up to ≈17.3 °C depending on their color, compared to their conventional counterparts. With additional chromatic features, ECRC can further enhance the availability of radiative cooling technology for practically realizing the energy‐saving structures in real‐world architectural circumstances. [ABSTRACT FROM AUTHOR]

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To pave the way towards buildings' decarbonization in the context of the European Union's (EU) policy, the methodology of cost-optimality assessment based on regulation 244/2012/EU is a useful tool to explore and foster the application of energy technologies in buildings. Meanwhile, the fostering of concentrated solar power is included in the EU solar energy strategy. In this study, the cost-optimal methodology is employed for the techno-economic assessment of the integration of a novel solar, multi-purpose energy technology, namely a parabolic trough collector-based trigeneration system, in two building types with different characteristics, namely an office and a hospital, in Greece, thus allowing the evaluation of the cost-optimal system design and the impact of the building type on the system's techno-economic performance. Reference buildings are defined and their energy demand is calculated through dynamic energy simulations. The trigeneration system's performance for different design scenarios is then parametrically investigated using a simulation model. For each scenario, energy, environmental and economic indicators are calculated and the cost-optimal designs are extracted. In the cost-optimal implementation, the system covered 18.19–36.39% and 3.58–15.71% of the heating and cooling demand, respectively, while the reduction of the primary energy consumption and emissions was estimated at 10–14% and 10–16%, respectively. However, differences between the buildings related to the operation schedule and the loads led to the implementation of the system being economically more attractive in the hospital, while for the office, financial support is necessary for a viable investment. [ABSTRACT FROM AUTHOR]

Constraining the processes that drive coronal heating from observations is a difficult task due to the complexity of the solar atmosphere. As upcoming missions such as the Multi-slit Solar Explorer (MUSE) will provide coronal observations with unprecedented spatial and temporal resolution, numerical simulations are becoming increasingly realistic. Despite the availability of synthetic observations from numerical models, line-of-sight effects and the complexity of the magnetic topology in a realistic set-up still complicate the prediction of signatures for specific heating processes. 3D magnetohydrodynamic (MHD) simulations have shown that a significant part of the Poynting flux injected into the solar atmosphere is carried by small-scale motions, such as vortices driven by rotational flows inside intergranular lanes. MHD waves excited by these vortices have been suggested to play an important role in the energy transfer between different atmospheric layers. Using synthetic spectroscopic data generated from a coronal loop model incorporating realistic driving by magnetoconvection, we study whether signatures of energy transport by vortices and eventual dissipation can be identified with future missions such as MUSE. [ABSTRACT FROM AUTHOR]

The efficient use of renewable energy sources becomes necessary due to rise in energy demand and dwindling traditional energy sources. In present work, solar water heating system (SWHS) is modified to improve its thermohydraulic performance. The absorber tube of the SWHS is modified by inserting the delta-shaped winglets (DSW) of different configurations inside it. Following variations of DSW geometrical parameters are considered in this study: pitch ratio ( P Rd) from 0.5 to 2.0, blockage ratio (B Rd) from 0.1 to 0.25, attack angle (α) from 15˚ to 60˚, spacer length S w from 0 to 600 mm and Reynolds number from 200 to 1800. The results of the experiments reveal that out of considered geometrical parameters, DSW of geometrical parameters; P Rd of 0.5, B Rd of 0.2, α of 45˚and S w of 0 mm affect Nusselt number ( Nu ) and friction factor (f ) optimally. The empirical correlations for Nu , f and thermohydraulic performance ( η w ) are developed from experimental values. Modelling for predictions of Nu , f and η w using artificial neural networks (ANNs) is also executed. The values of Nu and f obtained experimentally and from developed correlation are within bias errors of 10.9% for Nu and 9.5% for f , respectively. Novel aspects of this research include the utilisation of DSW hindrance promoters in the absorber tube for performance enhancement, development of empirical correlations, and predictions of outcomes using artificial neural networks. Correlation generation and modelling using the ANNs technique are essential aspects of this study that help to optimise the design parameters of similar type of SWHS. [ABSTRACT FROM AUTHOR]

Managing solar energy utilization and water heating in multi-apartment buildings presents formidable challenges due to limited space for solar collector installation. Optimizing heat energy distribution among communal consumers is crucial, necessitating precise regulation of hot water flow from the main system line to individual thermal storage tanks. The objective is to minimize heat and electricity losses while maximizing temperature levels in each tank. An electronic control system, centered around a microcontroller, has been developed with an efficient algorithm, data storage memory, and communication capabilities. The implemented solar heating system is tailored to each individual consumer, incorporating precise measurements for every apartment. This customization enhances efficiency not only for the individual consumer but also benefits the overall solar system within the building. This article explores the development and past outcomes of implementing such a control system, highlighting its significant advantages, particularly in multi-story buildings. [ABSTRACT FROM AUTHOR]

The cutoff effect is a significant determinant of solar magnetohydrodynamic wave propagation and hence pivotal in energy transfer studies, such as solar plasma heating and seismological diagnostics. Despite continuous efforts, no good agreement between observed waveperiods and theory or numerical simulations was found. Our objective is to investigate the magnetoacoustic cutoff effect in the partially ionized solar atmosphere, factoring in the two-fluid effects. We developed a two-fluid MHD numerical model and used it to simulate a quiet region of the Sun from the top of the convective zone to the low corona. Our findings show that the ongoing granulation excites a wide range of waves propagating into the upper atmospheric layers. The cutoff waveperiods strongly depend on the height. Two-fluid waveperiods obtained with numerical simulations reproduce the recent observations at a very good level of compliance. Furthermore, direct comparison with strongly coupled cases that imitate the single-fluid approximation have shown that the waveperiod propagation pattern is only present in fully two-fluid simulations. We conclude that the presence of neutrals and therefore collisional terms change the dynamics of the magnetized plasma, in comparison with the single-fluid approximation. This effect is more prominently seen in the upper photosphere and chromosphere. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'. [ABSTRACT FROM AUTHOR]

Currently, solar heating systems face several challenges in winter cold conditions, including low heat collection temperature, high heat collection loss, low thermal storage density, and unstable storage temperature, making it difficult to meet heating quality requirements. Taking the heating of a driving school building in the suburbs of Baiyin, Gansu as a case study, and using typical meteorological data for the local heating season, we simulated the indoor thermal load of the building using DEST software. We then designed a focused solar heating system with phase change thermal storage, coupling focused solar thermal technology with latent heat storage technology. The thermal storage performance of Ba(OH)2-8H2O composite phase change material in an oil-sealed environment was verified. Mathematical models of the major components of the focused solar heating system with phase change storage were developed, along with a TRNSYS system model. An objective function was established using the annualized cost method, with the area of the collector and the mass of PCM as variables. Optimization was performed using Genopt software, invoking the Hooke-Jeeves algorithm to optimize the heat collection area S and mass m of phase change material in the focused solar heating system. The optimized results showed a collector area of 4.11 m2, and a PCM mass of 130 kg, resulting in a 10.04% improvement in the solar assurance rate. Over the system's entire lifecycle, the cost decreased by 1025 RMB, and the carbon emission reduction increased from 10,838 to 16,101 kg. [ABSTRACT FROM AUTHOR]

Seasonal storage of solar thermal energy through supercooled phase change materials (PCM) offers a promising solution for decarbonizing space and water heating in winter. Despite the high energy density and adaptability, natural PCMs often lack the necessary supercooling for stable, long-term storage. Leveraging erythritol, a sustainable mid-temperature PCM with high latent heat, we introduce a straightforward method to stabilize its supercooling by incorporating carrageenan (CG), a bio-derived food thickener. By improving the solid-liquid interfacial energy with the addition of CG the latent heat of erythritol can be effectively locked at a very low temperature. We show that the composite PCM can sustain an ultrastable supercooled state below −30 °C, which guarantees no accidental loss of the latent heat in severe cold regions on Earth. We further demonstrate that the common ultrasonication method can be used as the key to unlocking the latent heat stored in the CG-thickened erythritol, showing its great potential to serve as a high-performance, eco-friendly PCM for long-term seasonal solar energy storage. To enable high-performance seasonal thermal energy storage for decarbonized solar heating, the authors propose an effective method to realize ultrastable supercooled erythritol, with an ultrahigh supercooling >150 ˚C, by making it more viscous. [ABSTRACT FROM AUTHOR]

The development of functional textiles combining conventional apparel with advanced technologies for personal health management (PHM) has garnered widespread attention. However, the current PHM textiles often achieve multifunctionality by stacking functional modules, leading to poor durability and scalability. Herein, a scalable and robust PHM textile is designed by integrating electrical, radiative, and solar heating, electromagnetic interference (EMI) shielding, and piezoresistive sensing performance onto cotton fabric. This is achieved through an uncomplicated screen‐printing process using silver paste. The conductivity of the PHM textile is ≈1.6 × 104 S m−1, ensuring an electric heating temperature of ≈134 °C with a low voltage of 1.7 V, as well as an EMI shielding effectiveness of ≈56 dB, and human motion monitoring performance. Surprisingly, the radiative/solar heating capability of the PHM textile surpasses that of traditional warm leather. Even after undergoing rigorous physical and chemical treatments, the PHM textile maintains terrific durability. Additionally, the PHM textile possesses maneuverable scalability and comfortable wearability. This innovative work opens up new avenues for the strategic design of PHM textiles and provides an advantageous guarantee of mass production. [ABSTRACT FROM AUTHOR]

The paper presents the performance evaluation of a modified indirect solar dual collector dryer (MIS2CD) integrated with a thermal storage system for drying myrobalan slices. The design of the solar collector and solar collector with thermal storage was to supply uninterrupted thermal energy to the drying chamber during sunny and sunset hours. To evaluate the dryer performances, one lot (20 kg) of myrobalan was dried in the MIS2CD, and as a result, the thermal efficiency and energy supply period of MIS2CD increased by 12 ± 02% and 41 ± 1.2%, respectively. Drying characteristics of myrobalan slices in MIS2CD, TD, and OSD were studied and compared. A two-term exponential model best explains the drying kinetics of myrobalan slices dried in MIS2CD. The dried sample in MIS2CD results in lesser ΔE* values than TD and OSD methods. The highest exergy efficiency of 78.2% and lower exergy losses were recorded. The energy payback period of the MIS2CD was evaluated as 1.42 years. The CO2 emitted and CO2 reduced reduction are calculated for drying myrobalan in MIS2CD for a lifetime (20 years) of 67.85 kg and 20.65 tons, respectively. The capital cost of the solar dryer design was estimated depending on the economic considerations of the state. The drying hours were increased in MIS2CD against OSD by 59% on the annual sunny days (210 days). The sample drying period MSD and TD to reach the final moisture level of 7% was 9 h and 5 h, respectively. The total economic benefit is 22,622 INR (annually), and the 2.08 benefit–cost ratio for myrobalan dried in MIS2CD compared to TD. The MIS2CD's payback period is nearly 2.18 years, much less than the dryer's lifetime. [ABSTRACT FROM AUTHOR]

Solar concentrating systems can play a critical role in the future for designing sustainable cities. The goal of this investigation is the energy analysis of a solar-driven power plant based on the solar dish collector, storage thermal tank and a reheating organic Rankine cycle. The present thermodynamic cycle is a more efficient choice compared to other similar designs due to the existence of a double expansion with an intermediate reheating. Also, the use of the solar dish collector enables efficient operation in medium and high temperatures. More specifically, this investigation is performed on dynamic conditions aiming to determine the unit's performance on a usual summer day. The analysis is done with a dynamic model based on mathematical formulas which are inserted into engineering equation solver. The simulation results proved that a collecting area of 500 m² (50 modules) coupled with a storage tank of 5 m³ volume that feeds an organic Rankine cycle of 50 kWel nominal power leads to daily electricity production of 577 kWhel. The system efficiency is found to be 12.6%, the thermodynamic cycle efficiency 20.8% and the solar field thermal efficiency 60.8%. Therefore, it is obvious that the suggested unit leads to satisfying results, and it is a promising one for the design of sustainable renewably driven units in the future. [ABSTRACT FROM AUTHOR]

In terms of environmental sustainability, the barriers—and interactions between these barriers—to the use of solar energy for active and passive heating in residential buildings stem from location-specific housing production patterns and the actors involved in these patterns. A clear definition of hierarchies and priorities between barriers helps managers set strategic priorities and action plans to find solutions. After the earthquake in Van in 2011, 6000 hectares of land were opened for new development, and research using the sampling method discovered that the most common type of housing production in the city is the build-to-sell housing production method. The actors involved in build-to-sell housing production are technical staff, local–central administrations, entrepreneurs, end users, landowners, financial companies, non-governmental organizations, and building inspection institutions. This article examines the barriers to the use of solar energy for active and passive heating purposes, the interactions between these barriers using ISM and MICMAC methods, and the build-to-sell housing production method and actors. Barriers were identified through a literature review and semi-structured interviews. The barriers were further categorized under eight main headings according to their subject matter. The hierarchies of barriers in creating problems and solutions were determined using ISM and MICMAC methods and the findings were interpreted. In the City of Van, with regard to the houses produced via the build-to-sell production method, the barriers against the use of solar energy for heating purposes in houses considering active and passive methods are ranked in order of priority in creating the problem and the solution. Barriers caused by political and administrative issues are ranked first; barriers caused by social awareness and end users are ranked second; barriers caused by social and sociological events are ranked third; barriers caused by laws and regulations are ranked fourth; barriers caused by the knowledge, skills, and awareness of designers are ranked fifth; barriers caused by deficiencies in technical issues are ranked sixth; and barriers caused by economic and financial issues are ranked seventh. Even though the barrier caused by the working mode of build-to-sell productions is the largest in creating the problem, it is the least effective barrier to solving the problem in the ISM hierarchical and MICMAC schemes. The research process is presented in the Methods section. [ABSTRACT FROM AUTHOR]

The design and performance of a shallow geothermal system is influenced by the geological and hydrogeological context, environmental conditions and thermal demand loads. In order to preserve the natural thermal resource, it is crucial to have a balance between the supply and the demand for the renewable energy. In this context, this article presents a case study where an innovative system is created for the storage of seasonal solar thermal energy underground, exploiting geotechnical micropiles technology. The new geoprobes system (energy micropile; EmP) consists of the installation of coaxial geothermal probes within existing micropiles realized for the seismic requalification of buildings. The underground geothermal system has been realized, starting from the basement of an existing holiday home Condominium, and was installed in dry subsoil, 20 m-deep below the parking floor. The building consists of 140 apartments, with a total area of 5553 m2, and is located at an altitude of about 1490 m above sea level. Within the framework of a circular economy, energy saving and the use of renewable sources, the design of the geothermal system was based on geological, hydrogeological and thermophysical analytical studies, in situ measurements (e.g., Lefranc and Lugeon test during drilling; Rock Quality Designation index; thermal response tests; acquisition of temperature data along the borehole), numerical modelling and long-term simulations. Due to the strong energy imbalance of the demand from the building (heating only), and in order to optimize the underground annual balance, both solar thermal storage and geothermal heat extraction/injection to/from a field of 380 EmPs, with a relative distance varying from 1 to 2 m, were adopted. The integrated solution, resulting from this investigation, allowed us to overcome the standard barriers of similar geological settings, such as the lack of groundwater for shallow geothermal energy exploitation, the lack of space for borehole heat exchanger drilling, the waste of solar heat during the warm season, etc., and it can pave the way for similar renewable and low carbon emission hybrid applications as well as contribute to the creation of smart buildings/urban areas. [ABSTRACT FROM AUTHOR]

[Display omitted] Outdoor radiative cooling is a passive method of cooling a surface that faces the sky. During the past decade, numbers of successful demonstrations of daytime radiative coolers have been reported. Because a daytime radiative cooler can be radiatively cooled both during the day and at night, it is always cooled and a temperature difference against the surroundings is generated. This temperature difference can be used to generate thermoelectric power throughout the day by placing a daytime radiative cooler on a thermoelectric module. However, such a device cannot harvest solar heat because sunlight is reflected by the daytime radiative cooler. In this study, a thermoelectric device that simultaneously harvests both radiative cooling and solar heating is presented. The essential component is a vertically placed thermoelectric module made of transparent thermoelectric thin films which allows radiatively cooled and solar heated surfaces to be co-planar. The outdoor and indoor measurements confirm that the device can harvest both radiative cooling and solar heating simultaneously during the day without offsetting each other, and can harvest radiative cooling at night. The co-planar design is an efficient method for simultaneously harvesting solar heating and radiative cooling, which could facilitate efficient energy harvesting and can be applied to a standalone power supply for off-grid sensor modules. [ABSTRACT FROM AUTHOR]

This work focuses on the structure, working, and testing of a new mixed solar cooker using a linear Fresnel collector, evacuated tube and box‐type cooker. The low‐cost components used in the construction of this cooker can help it satisfy the needs of both urban and rural inhabitants who need steady cooking temperatures above 140°C. A family of five can prepare four meals using this modified solar cooker, which costs about $250. The designed solar cooker was tested by conducting no‐load and full‐load tests. For the no‐load test, the maximum temperature of the absorber plate and oil for the new mixed cooker was recorded as 160.26°C and 172.72°C, respectively. The absorber plate of the new mixed cooker and its oil both reached their highest temperatures during the full‐load test at 141.14°C and 157°C, respectively. The energy efficiency of the new cooker is 58.776%, while its exergy efficiency is 13%. The heat transfer coefficient increased to 100.16 W/m² °C. This cooker provides an additional time savings of 60 min. An improvement of 27.5% in the highest temperature reached was seen when the developed cooker's performance was compared with those reported in the literature. Additionally, the new cooker's heat‐storing capability enables up to 3 h of autonomy. The Levelized Cost of Cooking a Meal for the innovative mixed solar cooker is $0.034 per meal. [ABSTRACT FROM AUTHOR]

This paper proposes an investigation of a novel design of receiver absorber tube (circular-trapezoidal shaped) for parabolic trough concentrator (PTC) system aiming at catching a part of the lost (reflected) solar rays due to effects related to the incidence angle deviation and thus improving the PTC's thermal performance. Although they are always present in PTC, the effects of the deviation angle are often not considered in the literature. These effects are considered here in view of presenting a better and more useful focal area, the optimal circular-trapezoidal absorber tube shape is determined according to the maximal limit of the deviation angle that allows catching the maximum amount of solar rays. The corresponding model is established considering it as a two-dimensional problem and the derived deviation angle coefficient is compared to that obtained for a traditional circular-shaped tube. Moreover, the energy balance model is adapted to simulate the thermal efficiency of the considered tubes as a function of the deviation angle with some assumptions. The obtained results prove that from a deviation angle value of 0.1 deg, the gain in efficiency becomes more significant; it can reach 5% and even be higher for a deviation angle value of 0.5 deg. Finally, comsol multiphysics software package was used to determine the pressure drops, temperature, and velocity field distributions, considering a deviation angle value of 0.2 deg. The results confirm that the proposed tube absorbs more heat than the traditional one. [ABSTRACT FROM AUTHOR]

The current paper experimentally studied the performance of solar-driven internally cooled liquid desiccant system for hot and humid climates using CaCl2 as a liquid desiccant. The system is designed to investigate the input conditions of the room by adjusting various air and solution variables. This internally cooled liquid desiccant system consists of the dehumidifier and regenerator in a single module and the regeneration of the solution is done by solar energy. The present study analyzes the effect of solution concentration, air mass flow rate and solution volume flow rate using different performance indices such as humidity reduction, moisture effectiveness, enthalpy effectiveness, and COP. The results demonstrate that the maximum moisture reduction of 4.2 g/kg d.a. is found at an airflow rate of 0.03195 kg/s, a solution volume flow rate of 12.5 LPM, and a solution concentration of 37%, while the maximum COP of 0.274 is obtained at an airflow rate of 0.0715 kg/s, a solution volume flow rate of 12.5 LPM, and a solution concentration of 37%. The maximum moisture and enthalpy effectiveness are obtained as 24.1% and 26.2%, respectively. The paper also presents the correlations for moisture and enthalpy effectiveness based on findings from experiments. [ABSTRACT FROM AUTHOR]

A hybrid system called photovoltaic/thermal (PV/T) is the combination of photovoltaic (PV) and solar thermal collector (STC) to simultaneously produce heat and electricity. The combination optimizes the use of solar energy, functioning as a heat source for water heating and mitigating the low PV efficiency issue caused by module high temperature. Therefore, this research aimed to investigate and compare the efficiency of PV, PV/T, and STC, with heat pipe (HP) as heat-absorbing media to warm water. The systems were experimented with the same conditions at ambient temperatures of 27-40°C and solar intensity of 122-967 W/m², at intervals between 08.00 AM to 04.00 PM during 8 days of testing. The experiment was conducted by directly measuring the intensity of the sun, water temperature, as well as thermal and electrical energy generated by the systems. The results showed that PV and HP-PV/T had average electrical energy efficiency of 16.92% and 17.68%, respectively, indicating a 0.76% increase. Furthermore, there was a difference in average thermal efficiency of 1.72% between HP-PV/T and HP-STC, with values of 22.93% and 24.65%, respectively. These results offered a promising implication for the development of PV/T for residential applications. [ABSTRACT FROM AUTHOR]

The present study models and examines a novel integrated process of fast pyrolysis of biomass using a system of solar type of heliostat and a system of energy storage by thermochemical method. This integrated model enables biomass pyrolysis to produce bio-oil, reducing the need of external heat and improving efficiency of pyrolysis. The discussion focuses on three: daily, weekly, and yearly, scenarios for storing solar energy. In addition, the evaluation includes assessing the solar fraction, size of the storage devices, power load of auxiliary heating device, and energyefficiency. The modeling and simulation tasks were conducted using Aspen Plus and Engineering Equation Solver. According to the findings, 0.680 kg per second pyro-oil can be generated from one kilogram per second biomass (hybrid poplar). Also 0.170 kg per second char and 0.160 kg per second gases could be yielded from one kilogram per second of the mentioned biomass. The integrated system yields a solar fraction of 0.850 as the resulting outcome. By utilizing the storage system, the thermal energy needed for pyrolysis system can be reduced from 36.49 to 3.929 MW. [ABSTRACT FROM AUTHOR]

The implementation of strategies aimed at curtailing energy consumption and carbon emissions in buildings is of paramount importance. Priority should be accorded to the reduction of embodied carbon emissions from construction materials and operational carbon emissions during the usage phase. A public building situated in an extremely cold region is chosen as the subject of this study. An initial investigation is conducted into the impact of various enclosure structure materials on embodied carbon. The impact of different heating, ventilation and air conditioning (HVAC) systems on the total carbon emissions of public buildings are studied as well. The findings indicate that the amalgamation of W3 + R + G4 + H4 culminates in the least total carbon emissions. Upon establishing the foundational scheme for the public building, an optimization (nondominated sorting genetic algorithm II [NSGA II] and Criteria Importance Through Intercrieria Correlation [CRITIC]) of the enclosure structure parameters is initiated to examine the optimal parameters of the public building's enclosure structure. The findings reveal that a decrease in the heat transfer coefficient could trigger an increase in total carbon emissions. This is attributed to the fact that the carbon emissions embodied in the production process of these materials could potentially outweigh the reduction observed in operational carbon emissions. Further adjustments were also made to the parameters of the HVAC system in the buildings. The findings indicate that within the context of public buildings, given the presence of optimal parameters and an HVAC system that utilizes solar energy for both heating and cooling in the American Society of Heating, Refrigerating and Air‐Conditioning Engineers, Inc. 6 A climatic zone, the efficiency of the cooling system can exert a significant influence on the operations carbon emissions reduction. [ABSTRACT FROM AUTHOR]

Shallow geothermal heat has the characteristics of wide distribution and huge reserves. However, for northern rural buildings, the heating load in winter is much greater than the cooling load in summer, and thermal imbalance of the soil is prone to occur. This paper takes rural residences in southern Hebei as an example and designs a solar-assisted shallow geothermal energy system. Compared with the original shallow ground-source heat pump system, the indoor and outdoor temperature differences of the target building were first analyzed. Second, the changes in the soil temperature field and the differences in the supply and return water temperature were monitored. Finally, the initial investment and operating costs of the assisted system are analyzed. The results show that the average ground temperature field increases significantly in winter. Through the alternate operation of solar energy and ground-source heat pumps, heat extraction from the ground is reduced, and the imbalance cycle of heat extraction in winter and heat removal in summer is shortened. It alleviates the imbalance of the cold and heat loads for soil throughout the year. The inlet and outlet water temperature and heat exchange efficiency of the buried pipes have been significantly improved. The energy efficiency ratio of the system using the assisted system has increased from 3.40 in 2020 to 4.17, an increase of 0.77. The optimal ratio of the solar- assisted shallow geothermal energy system is a 12.80 m2 solar heat-collection area and one buried hole. The winter heating operating cost of the solar-assisted shallow geothermal energy system is 18.86 CNY/m2. It can save 37% of the annual operating costs of heating, cooling, and hot water compared to a single ground-source heat pump system and 40%–45% compared to traditional heating and cooling modes. [ABSTRACT FROM AUTHOR]

Thermochromic (TC) smart window which allows modulating the transmission of solar heat energy and sunlight in response to environmental conditions has great potential for improving the building energy and daylighting performance simultaneously. In this study, the multi-objective optimization method is used to determine the ideal optical properties of TC windows. Parametric assessment is firstly conducted to investigate the influence of several crucial parameters. Multi-objective optimization is then carried out by applying Non-dominated Sort Genetic Algorithm-III, maximizing daylight availability and building energy efficiency. Finally, the decision-making of the Pareto frontier is performed to achieve the ideal TC windows in 32 representative cities in different climatic zones of China. Results demonstrate that increasing the luminous transmittance at low-temperature and decreasing luminous transmittance modulation ability are beneficial to daylighting and energy performance. Lower solar transmittance at low-temperature contributes to building energy savings in Beijing, Shanghai, Guangzhou and Kunming, except for Harbin. Higher solar transmittance modulation ability is desired for building energy efficiency. The optimum value for the transition temperature is in the range of 23.67–38.85°C. The building energy consumption can be reduced by 13.01%, and the desired daylighting hours can be improved by 8.90%, relative to the clear double-glazed windows. [ABSTRACT FROM AUTHOR]

We present statistical analysis of 16,903 current sheets (CSs) observed over 641 days aboard Ulysses spacecraft at 5 AU. We show that the magnetic field rotates across CSs through some shear angle, while only weakly varies in magnitude. The CSs are typically asymmetric with statistically different, though only by a few percent, magnetic field magnitudes at the CS boundaries. The data set is classified into about 90.6% non‐bifurcated and 9.4% bifurcated CSs. Most of the CSs are proton kinetic‐scale structures with the half‐thickness of non‐bifurcated and bifurcated CSs within respectively 200–2,000 km and 500–5,000 km or 0.5–5λp and 0.7–15λp in units of local proton inertial length. The amplitude of the current density, mostly parallel to magnetic field, is typically within 0.05–0.5 nA/m2 or 0.04–0.4JA in units of local Alfvén current density. The CSs demonstrate approximate scale‐invariance with the shear angle and current density amplitude scaling with the half‐thickness, Δθ≈16.6°λ/λp0.34 ${\Delta }\theta \approx 16.6{}^{\circ}\,{\left(\lambda /{\lambda }_{p}\right)}^{0.34}$ and J0/JA≈0.14λ/λp−0.66 ${J}_{0}/{J}_{A}\approx 0.14\,{\left(\lambda /{\lambda }_{p}\right)}^{-0.66}$. The matching of the magnetic field rotation and compressibility observed within the CSs against those in ambient solar wind indicate that the CSs are produced by turbulence, inheriting its scale‐invariance and compressibility. The estimated asymmetry in plasma beta between the CS boundaries is shown to be insufficient to suppress magnetic reconnection through the diamagnetic drift of X‐line. The presented results will be of value for future comparative analysis of CSs observed at different distances from the Sun. Plain Language Summary: Current sheets (CSs) are coherent structures potentially contributing to solar wind heating and particle acceleration. These structures are highly‐likely produced by turbulence, but the alternative hypothesis of coronal origin has not been ruled out. The analysis of CSs at different distances from the Sun may potentially shed light onto the origin and contribution of these structures to solar wind heating and particle acceleration. While there are comprehensive analyses of solar wind CSs at 1 AU and near the Sun, there is still no equivalent analysis of these structures well beyond 1 AU. In this study we present an extensive statistical study of CSs observed aboard Ulysses around 5 AU. We demonstrate that the CSs are predominantly rotations of the magnetic field, typically occurring on proton kinetic scales and exhibiting approximate scale‐invariance. We provide strong evidence that the CSs are produced by turbulence and inherit the scale‐invariance and magnetic field compressibility typical of turbulence. The presented results will be valuable for understanding solar wind turbulence, solar wind heating and particle acceleration at different distances from the Sun. Key Points: Current sheets (CSs) are predominantly rotations of the magnetic field on proton kinetic scalesScale‐invariant properties strongly indicate that CSs are produced by turbulenceThe asymmetry of CSs is typically insufficient to suppress magnetic reconnection [ABSTRACT FROM AUTHOR]

In areas with a deep floor plan, the distribution of natural light is not uniform. Consequently, relying solely on daylight may not suffice to meet the space's lighting requirements, necessitating the use of artificial lighting in darker areas. Therefore, a lighting system is needed that not only controls the glare near the windows but also increases the light at the end of the room and provides uniform daylight. One of the widely used systems is the "light shelf", which has three main functions: shading, increasing the depth of light penetration, and reducing glare. Review articles about light shelves were published in 2015 and 2017, while more than 80% of the studies have been carried out since 2016, and light shelves with more diverse forms and dynamic elements and many consolidations have been proposed. Therefore, there is a need for a more comprehensive review. The main question of this research is how different parameters (including climate, material, ceiling, and integrated systems) can help to increase the efficiency of light shelves. By using a systematic review, studies in the past three decades were classified in order to determine the effect of these parameters on improving lighting performance and controlling solar heat gain. [ABSTRACT FROM AUTHOR]