Mussad Mohammed Al-Zahrani^*, Taher Maatallah

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1883-1905, 2025, DOI:10.32604/fhmt.2025.074656 - 31 December 2025

Abstract Conventional concentrator photovoltaics (CPV) face a persistent trade-off between high efficiency and high cost, driven by expensive multi-junction solar cells and complex active cooling systems. This study presents a computational investigation of a novel Multi-Focal Pyramidal Array (MFPA)-based CPV system designed to overcome this limitation. The MFPA architecture employs a geometrically optimized pyramidal concentrator to distribute concentrated sunlight onto strategically placed, low-cost monocrystalline silicon cells, enabling high efficiency energy capture while passively managing thermal loads. Coupled optical thermal electrical simulations in COMSOL Multiphysics demonstrate a geometric concentration ratio of 120×, with system temperatures maintained below More >

Jinyou Qiu^1,2, Jiale Liu^1,2, Yubing Li^1,2,*, Shaogeng Zhong³, Guilong Dai^1,2, Wenhua Liu⁴

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 2025-2049, 2025, DOI:10.32604/fhmt.2025.072260 - 31 December 2025

Abstract The growing demand for energy-saving and renewable heating solutions has made photovoltaic/thermal (PV/T) heat pump systems a promising technology. However, their thermal and electrical performance, as well as the overall utilization of solar energy, strongly depend on capacity configuration and operating parameters. To address this issue, this study proposes a PV/T heat pump system featuring a novel rhombic flow channel structure that functions as the collector-evaporator. An experimental test bench was established to evaluate system performance, and a one-dimensional numerical model was developed to investigate the effects of environmental and operating parameters. The simulation results… More > Graphic Abstract

Lei Wang¹, Hongyang Zhou², Xiaofan Liu³, Junkun Mu², Jinpeng Bi², Youkang Jin², Juan Ge², Yuexia Lv^2,4,*

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1811-1832, 2025, DOI:10.32604/fhmt.2025.071222 - 31 December 2025

Abstract Membrane gas absorption and solar-assisted absorbent regeneration offer a sustainable approach to reduce the energy penalty of post-combustion CO₂ capture. This study introduces a novel system integrating solar thermal energy with membrane gas absorption to capture CO₂ from a 580 MWe pulverized coal power plant. The environmental impacts across six scenarios at varying solar fractions are evaluated via life cycle assessment. Results show a 7.61%–13.04% reduction in global warming potential compared to a steam-driven CO₂ capture system. Electricity and steam consumption dominate the operational phase, contributing 15%–64% and 18%–61% to environmental impacts in non-TES scenarios, respectively. While More >

Y.C. Rodríguez-Gómez¹, J. Serrano-Arellano^1,*, F.N. Demesa-López¹, J.M. Belman-Flores², J.F. Ituna-Yudonago³

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 2073-2107, 2025, DOI:10.32604/fhmt.2025.069564 - 31 December 2025

Abstract The Trombe Wall (TW) is a low-cost, passive heating system known for its high thermal efficiency, particularly in cold and temperate climates. Recent research has explored its adaptability to warm-dry climates with high thermal variability, such as those found in central Mexico. This study presents a dynamic simulation-based analysis of the TW’s thermal performance in a representative social housing unit located in Pachuca de Soto, Hidalgo. Two models were compared—one with a south-facing TW system and one without—to evaluate indoor thermal comfort throughout a full annual cycle. The simulations were conducted using OpenStudio and EnergyPlus,… More > Graphic Abstract

Noor Moneer Basher¹, Omar Rafae Alomar^1,*, Omar Mohammed Ali², Diyar Abdullah Ahmed³

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 2001-2024, 2025, DOI:10.32604/fhmt.2025.066997 - 31 December 2025

Abstract The energy consumption of a Split air conditioning unit (ACU) inside a building is extremely large, and efforts to decrease this issue are ongoing. The current work aims to experimentally investigate the thermal performance of ACU using an external cooling-water loop for pre-cooling the condenser to improve the efficiency and to reduce energy consumption by reducing refrigerant temperature before entering the condenser, thereby reducing the coefficient of performance. The experiments are performed on ACU with and without using an external cooling-water loop under different climate conditions. By using the experimental data, the systems’ performances for… More >

Hauwau Kaoje^1,2, Adekunle Adeleke^2,3,*, Esther Anosike-Francis^2,3, Seun Jesuloluwa^2,3, Temitayo Ogedengbe^2,3, Hauwa Rasheed², Jude Okolie⁴

Journal of Renewable Materials, Vol.13, No.12, pp. 2375-2430, 2025, DOI:10.32604/jrm.2025.02025-0109 - 23 December 2025

Abstract The increasing need for sustainable energy and the environmental impacts of reliance on fossil fuels have sparked greater interest in biomass as a renewable energy source. This review provides an in-depth assessment of bio-oil and biochar generation through the pyrolysis of sawdust, a significant variety of lignocellulosic biomass. The paper investigates different thermochemical conversion methods, including fast, slow, catalytic, flash, and co-pyrolysis, while emphasizing their operational parameters, reactor designs, and effects on product yields. The influence of temperature, heating rate, and catalysts on enhancing the quality and quantity of bio-oil and biochar is thoroughly analyzed. More > Graphic Abstract

Tariq Ali^1,2,*, Muhammad Ayaz^1,2, Mohammad Hijji², Imran Baig³, MI Mohamed Ershath⁴, Saleh Albelwi²

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.3, pp. 3839-3858, 2025, DOI:10.32604/cmes.2025.073169 - 23 December 2025

Abstract The integration of renewable energy sources into electricity markets presents significant challenges due to the inherent variability and uncertainty of power generation from wind, solar, and other renewables. Accurate forecasting is crucial for ensuring grid stability, optimizing market operations, and minimizing economic risks. This paper introduces a hybrid forecasting framework incorporating fractional-order statistical models, fractal-based feature engineering, and deep learning architectures to improve renewable energy forecasting accuracy. Fractional autoregressive integrated moving average (FARIMA) and fractional exponential smoothing (FETS) models are explored for capturing long-memory dependencies in energy time-series data. Additionally, multifractal detrended fluctuation analysis (MFDFA) More >

Mohamed Kouki¹, Nahid Osman², Mona Gafar³, Ragab A. El-Sehiemy^4,5,6,*

CMES-Computer Modeling in Engineering & Sciences, Vol.145, No.3, pp. 3783-3811, 2025, DOI:10.32604/cmes.2025.071964 - 23 December 2025

Abstract The growing integration of nondispatchable renewable energy sources (PV, wind) and the need to cut CO2 emissions make energy management crucial. Microgrids provide a framework for RES integration but face challenges from intermittency, fluctuating loads, cost optimization, and uncertainty in real-time balancing. Accurate short-term forecasting of solar generation and demand is vital for reliable and sustainable operation. While stochastic and machine learning methods are used, they struggle with limited data, complex temporal patterns, and scalability. Key challenges include capturing seasonal to weekly variations and modeling sudden fluctuations in generation and consumption. To address… More >

S. W. Jo^†, I. H. Kim^†, Y. J. Jeong^*

Chalcogenide Letters, Vol.22, No.3, pp. 189-196, 2025, DOI:10.15251/CL.2025.223.189

Abstract Copper selenide has emerged as a promising thermoelectric material due to its unique structural properties and tunable electronic band structure. However, its practical application is hindered by its relatively high thermal conductivity. In this study, we report on the turning of thermal conductivity and thermoelectric energy conversion by preparing a hybrid composite material including nano- and micro-sized Cu₂Se. By employing a hydrothermal synthesis method with cetyltrimethylammonium bromide (CTAB) as a surfactant, we successfully synthesized nano-sized Cu_₂Se particles with uniform size distribution. The incorporation of these nano-sized particles with micro-sized Cu₂Se resulted in a significant reduction in More >

S. Çelik^a,*, M. Temiz^b

Chalcogenide Letters, Vol.22, No.1, pp. 89-96, 2025, DOI:10.15251/CL.2025.221.89

Abstract In this study, PbZnS thin films with varying concentrations of lead (Pb) and zinc (Zn) were successfully produced using the spray pyrolysis method. The structural, optical and surface properties of the films were systematically investigated as a function of the Pb/Zn ratio. Xray diffraction (XRD) analysis confirmed the polycrystalline nature of the films, showing a cubic zinc blende structure with improved crystallinity as Pb content increased. Initially, with the increase in Pb concentration, larger crystallite sizes and decreased microstress were observed, but with the increase of Pb addition, the formation of secondary phases and the… More >