Accurate prediction of solar radiation plays a crucial role in optimizing the solar energy system design and enhancing the efficiency of photovoltaic power grid integration. However, due to the complex dynamic characteristics of solar radiation data, the realization of such a tough task faces a formidable challenge. To this end, this study presents a solar radiation prediction method which mainly consists of the high-quality data preprocessing technique and the frequency-domain physics-informed convolutional network (FD-PICN). This method can handle the complex characteristics embedded in the solar radiation data from the spatial-temporal-frequency domain. Specifically, multivariate fast iterative filtering is first employed to synchronously decompose the multi-station solar radiation data into a series of time-frequency consistent subseries where the spatiotemporal and time-frequency correlations among multiple stations are considered. Then, FD-PICN is designed to capture the evolution pattern of solar radiation by integrating cross-attention-assisted time-frequency feature extraction and two physical coherence functions (i.e., frequency-domain coherence function and phase lock value) for high-performance prediction. Finally, numerical examples grounded in the measured data from multiple stations are utilized to validate the capability of this method. Experimental analyses demonstrate that this method outperforms other compared methods across various predictive scenarios.

The conversion of solar radiation into thermal energy has gained increasing attention due to the growing demand for renewable sources of heat and electricity. Nanofluids, owing to their enhanced heat transfer capabilities, play a significant role in improving the efficiency of solar thermal systems. In this study, the flow of silicone oil containing diamond and silicon dioxide nanoparticles over a curved extended permeable sheet is investigated in the presence of Darcy-Forchheimer porous medium, thermal radiation, and Lorentz force. The non-Newtonian behavior of the working fluid is modeled using the Jeffrey fluid model. The governing flow equations are transformed into ordinary differential equations (ODEs) and solved numerically using the MATLAB bvp4c solver. Furthermore, an intelligent computational approach based on the Levenberg-Marquardt algorithm combined with a multilayer perceptron (MLP) feed-forward backpropagation artificial neural network is employed. The effects of key parameters, including the Deborah number, injection/suction parameter, permeability parameter, Forchheimer number, Hartmann number, curvature parameter, Prandtl number, Eckert number, and heat generation/absorption parameter, are analyzed in terms of pressure, velocity, temperature, and heat transfer rate. The results indicate that porous resistance and magnetic effects significantly influence boundary layer formation and heat extraction efficiency, showing that optimally adjusted hybrid nanofluids can greatly enhance thermal transfer in porous solar collectors and curved absorber surfaces, thus providing valuable insights for the design of advanced solar thermal systems.

The growing global energy demand and environmental concerns associated with fossil fuels have accelerated the adoption of renewable energy sources, especially solar photovoltaic (PV) systems. Grid-connected PV systems are widely preferred due to their ability to integrate seamlessly with existing power networks. However, their performance is affected by issues such as fluctuating solar irradiance, inefficient power extraction, and poor power quality. This thesis presents the design and control of a grid-connected solar PV system using an advanced Maximum Power Point Tracking (MPPT) technique and power quality enhancement methods. A comprehensive mathematical model of the PV array, DC-DC converter, and grid-connected inverter is developed and simulated in MATLAB/Simulink. The proposed intelligent MPPT algorithm improves tracking speed and minimizes oscillations compared to conventional methods like Perturb and Observe (P&O) and Incremental Conductance. To address power quality concerns, a grid-synchronized inverter with suitable filtering techniques is implemented to reduce harmonic distortion, voltage fluctuations, and poor power factor. Simulation results demonstrate improved MPPT efficiency, reduced Total Harmonic Distortion (THD), and enhanced voltage and current stability. This work offers an efficient solution for reliable grid integration of solar PV systems, supporting sustainable energy development. Keywords: Solar Photovoltaic (PV) System; Maximum Power Point Tracking (MPPT); Grid-Connected Inverter; Power Quality Improvement; Total Harmonic Distortion (THD).

This project aims to design and manufacture a passive solar tracking system to enhance the performance and efficiency of solar power systems. The proposed tracking system utilizes passive techniques that do not rely on active control mechanisms or external power sources, reducing complexity and energyconsumption. The project involves the conceptualization, design, prototyping, and testing of the passive solar tracking system to optimize the incident angleofsunlight on solar panels. The design process begins with a comprehensive study of solar tracking principles, including the movement of the Sun, geographical location considerations, and the effects of incident angle on energy capture. Variouspassive tracking mechanisms, such as bimetallic strips, compressed gas systems, and shape memory alloys, are evaluated to determine the most suitable approach for theproject. Based on the analysis, a novel passive tracking mechanism isdeveloped, taking into account factors such as simplicity, reliability, cost-effectiveness, and adaptability to different solar panel configurations. The design includes mechanical components, such as linkages, gears, and pivots, that enable the tracking system to follow the Sun's path autonomousy throughout the day. The outcome of this project is expected to demonstrate the feasibility and benefits of a passive solar tracking system in improving energy production and maximizing the utilization of solar resources. The findings can contribute to the development of more efficient and cost effective solar power systems, particularly in applications where active tracking systems may not be practical or economically viable. Keywords: passive solar tracking system, solar power systems, incident angle optimization,mechanical design, manufacturing, energy efficiency.

Adaptability design of solar heating systems in rural residences and model predictive control-based differentiated indoor temperature control: A case study in northern Shaanxi

Solar-powered unmanned aerial vehicles (UAVs) are emerging as long-endurance platforms for sensing, communications, and environmental monitoring with low operational emissions. Their performance depends on a tightly coupled energy ecosystem spanning photovoltaic harvesting, hybrid energy storage, power electronics, thermal regulation, aerodynamics, and autonomous flight control. From an energy-systems perspective, solar UAVs act as mobile testbeds for advanced photovoltaics, high–specific-energy batteries, and hybrid power-management strategies that are directly relevant to next-generation grids and storage technologies. This review provides a system-level synthesis of the technologies that define modern solar-powered UAVs, covering crystalline silicon, CIGS, perovskite, and multi-junction PV modules; lithium-based, solid-state, and Li–S storage; maximum power point tracking (MPPT) and power-management architectures; high-aspect-ratio aerodynamic structures; and propulsion and navigation subsystems. Key limitations—including weather-dependent irradiance, thermal and UV-induced material degradation, battery aging at high altitude, and regulatory constraints—are critically assessed to identify barriers to reliable multi-day and multi-week operation. Emerging trends such as flexible perovskite films, structural energy storage, solar–fuel-cell hybrid architectures, adaptive thermal management, and edge-AI autonomy are discussed as enablers of energy-positive, persistent flight. By consolidating fragmented insights from energy, materials, and aerospace literature, this review establishes an integrated framework to guide the design of next-generation solar UAV energy systems.

Abstract This paper presents a comprehensive investigation of the application of Phase Change Material (PCM) in a solar panel cooling system, focusing on its potential to enhance efficiency and power output. This is an important study of solar powered ships and boats in marine environment. The study employs a methodology, involving experimental measurements and data analysis, to evaluate the performance of the PCM-based cooling system. The results reveal a substantial reduction in solar panel temperature (up to 12°C), leading to significant improvements in efficiency and power output. Notably, PCM exhibits consistent performance across various environmental conditions, including different months and ambient temperatures. Paraffin wax with a melting temperature of 37°C is used as PCM, integrated with the Photo Voltaic (PV) panel. This research highlights the benefits and potential applications of PCM in solar panel cooling systems, demonstrating its ability to mitigate temperature-related losses and enhance overall solar panel performance. The findings have important implications for the design and optimization of solar panel systems, as well as thermal energy storage and renewable energy systems. The efficiency of solar panels has improved by 1.1%. using PCM material i.e. paraffin wax. This research targeting the Oman vision 2040 towards sustainable environment. This study also aims toward the united nation’s sustainable development goal of affordable and clean energy.

Solar Power Generation System (PLTS) for households equipped with an Internet of Things (IoT)-based control system is designed to improve efficiency and ease of energy usage monitoring. The research methods include the design of a household-scale solar power system, the integration of sensors for monitoring electrical parameters and environmental conditions, as well as the development of an IoT application for real-time control and monitoring. Data were collected through system testing on a household-scale simulation with variations in load and weather conditions.

The integration of photovoltaic (PV) generation with bidirectional electric vehicle (EV) fast-charging systems offers a promising pathway toward sustainable transportation and grid support. However, the dynamic coupling between maximum power point tracking (MPPT) perturbations and grid-side power quality presents a fundamental challenge in such multi-converter architectures. This paper addresses this challenge through a coordinated design and optimization framework for a grid-connected, PV-assisted bidirectional off-board EV fast charger. The system integrates a 184.695 kW PV array via a DC-DC boost converter, a common DC link, a three-phase bidirectional active front-end rectifier with an LCL filter, and a four-phase interleaved bidirectional DC-DC converter for the EV battery interface. A comparative evaluation of three MPPT algorithms establishes the Fuzzy Logic Variable Step-Size Perturb & Observe (Fuzzy VSS-P&O) as the optimal strategy, achieving 99.7% tracking efficiency with 46s settling time. However, initial integration of this high-performance MPPT reveals system-level harmonic distortion, with grid current total harmonic distortion (THD) reaching 4.02% during charging. To resolve this coupling, an Artificial Bee Colony (ABC) metaheuristic algorithm performs coordinated optimization of all critical PI controller gains. The optimized system reduces grid current THD to 1.40% during charging, improves DC-link transient response by 43%, and enhances Phase-Locked Loop (PLL) synchronization accuracy. Comprehensive validation confirms robust bidirectional operation with seamless mode transitions and compliant power quality. The results demonstrate that system-wide intelligent optimization is essential for reconciling advanced energy harvesting with stringent grid requirements in next-generation EV fast-charging infrastructure.

This Lake Toba, one of Indonesia’s most prominent tourist destinations, holds significantpotential to be developed into a sustainable and environmentally friendly tourism area through theintegration of renewable energy. Among the available options, solar energy utilization via SolarPhotovoltaic (PV) systems offers a strategic pathway to achieve energy sustainability and reducereliance on fossil fuels. This study aims to evaluate the solar radiation potential, land requirements,technical design of Solar PV systems, and economic feasibility to support sustainable ecotourismdevelopment in the Lake Toba region. A quantitative research approach was applied, combiningsolar radiation assessment based on Global Horizontal Irradiance (GHI) data from BMKG and theGlobal Solar Atlas with financial feasibility analysis using Levelized Cost of Electricity (LCOE),Net Present Value (NPV), and Payback Period metrics. The results indicate that the Lake Tobaregion receives an average solar radiation of 4.8–5.1 kWh/m²/day, allowing a 1 MWp Solar PVsystem to generate approximately 1.37 GWh of electricity annually. Economically, the systemyields an estimated LCOE of USD 0.056/kWh, significantly lower than diesel-based generationcosts of USD 0.15–0.20/kWh. Environmentally, such a system could reduce carbon emissions byaround 1,163 tons of CO₂ per year, directly supporting Indonesia’s national decarbonization argets. Overall, Solar PV deployment in the Lake Toba region is technically viable, economically competitive, and environmentally impactful, while also strengthening Lake Toba's image as a green tourism destination.

ABSTRACT Plant factories are an innovative agricultural model that leverage controlled environments and advanced regulation technologies to improve land‐use efficiency and reduce resource dependence. However, their development is constrained by high energy consumption. Given the high costs and environmental impacts associated with fossil‐fuel‐based electricity, renewable energy sources such as solar power have emerged as promising alternatives. In this study, a model vertical plant factory consisting of 20 stories (area = 100 m 2 ) was applied to 21 Chinese cities with populations exceeding 5 million. Three power supply modes were considered: a grid‐powered system, a standalone solar‐powered system, and a grid‐solar hybrid system. The net present cost (NPC), levelized cost of energy (COE), and carbon dioxide emissions were assessed for each mode. Among the three systems, the hybrid system substantially reduced economic costs (40.87%–65.68% lower NPC than the grid‐powered system), whereas the standalone solar‐powered system most effectively reduced carbon dioxide emissions (85.99%–97.93% lower than the grid‐powered system). By comprehensively analysing solar resources, system design, economic indicators, and emission reduction benefits, this study provides scientific evidence to support decision‐making and implementation of vertical agriculture farming projects, promoting the coordinated advancement of agriculture and environmental protection.

This article presents the development of software aimed at sizing photovoltaic solar installations, representing a significant advancement in optimizing the design and efficiency of solar systems. This software offers the possibility to accurately determine the dimensions of the components, taking into account environmental parameters, energy needs, as well as technical constraints, with the aim of achieving a reliable, efficient, and economical installation. This document presents a comprehensive reference framework regarding the software design process, the methodologies applied for sizing, as well as the analysis of the obtained results and their experimental validation.

This study details the design and execution of a solar-powered wireless power transfer system specifically designed for small household appliances. The system utilises solar energy as a sustainable power source and implements wireless power transfer technology to offer a convenient and effective alternative for powering low-power gadgets in a domestic setting. The emphasis is on resolving critical technical issues and enhancing system performance to provide a dependable power supply to various small appliances, such as smart home gadgets, IoT sensors, and portable electronics. The system provides flexibility, scalability, and environmental sustainability through an integration of solar panels, power electronics, and wireless communication modules, thereby promoting sustainable energy practices and improving user ease. The radiative approach was employed, dividing the system into segments, including receiving and transmitting modules. These modules consist of passive and active elements, including resistors, capacitors, and inductors of diverse values. The system consists of copper coils measuring L=0.5 m, a rectification circuit, a voltage regulator, an ESP8266 Wi-Fi module controller, a DCto-DC converter (LM2596) with a maximum output of 28 V DC and 2 A current, and an INA219 current sensor module with OLED units that display the system's activities and status. The system exhibited an optimal efficiency of 80%–95%, delivering an output power of 10 W, sufficient to charge various tiny devices, including phones, MP3 players, cameras, and other little household appliances with input power requirements between 3 and 9.5 W. The transmitter and receiver operate at a range of 2m to 5m, while the output current and voltage at the receiving end vary from 2V to 5V and 1.8A to 4A, respectively. Experimental validation and performance analysis demonstrate the feasibility and effectiveness of the constructed solar-based wireless power transfer system, highlighting its potential for practical implementation in modern households.

This study presents an integrated engineering methodology aligned with the planning phase of the ISO 50001:2018 (Energy Management Systems—Requirements with Guidance for Use. International Organization for Standardization (ISO): Geneva, Switzerland, 2018) energy management standard for the design, sizing, and assessment of a solar thermal system applied to domestic hot water production in a medium-scale hotel building. The proposed framework focuses on the energy review stage of ISO 50001, incorporating site-specific climatic assessment, spatial layout optimization, structural feasibility analysis, and energy performance evaluation to support informed technology selection and system viability. Thermal performance is assessed using real operational data from the case study, complemented by a data-driven multivariable regression-based energy performance indicator (EnPI) that relates electricity consumption to cooling degree days and room occupancy. This regression model, developed in accordance with ISO 50001 recommendations, enables transparent monitoring of energy performance under real operating conditions without relying on black-box predictive techniques. Material selection criteria for absorber plates, heat-transfer components, transparent covers, and insulation layers are discussed to support both initial efficiency and performance stability under site-specific climatic conditions. In addition, an indicative and qualitative analysis of material-dependent performance evolution is introduced to support comparative decision-making, without implying quantitative lifetime prediction. Structural feasibility of the collector support system is examined through finite-element simulations under combined gravitational and wind loads, providing illustrative verification of stress distribution under representative operating conditions. The installed system delivers an annual thermal energy contribution of 8468 kWh, resulting in an estimated reduction of 7.79 t of CO2 emissions per year. Economic indicators suggest a short payback period and a favorable internal rate of return, which should be interpreted as order-of-magnitude estimates within the planning scope of the methodology. Overall, the proposed methodology provides a replicable and multidisciplinary planning-phase framework aligned with ISO 50001 for the design and assessment of solar thermal systems in medium-scale buildings under real operating conditions.

One of the current world’s challenging issues concerns the design, development, and exploitation of efficient devices for energy harvesting that, in the last few years, has gathered a growing interest not only from academia but also from an industrial point of view. Although the general concept of (macro)energy harvesting has been successfully exploited for centuries in the design of passive solar power systems, as well as wind and water mills, only during the last 10 to 15 years there has been particular attention toward the development of effective (micro)energy harvesting systems, exploiting the energy from the ambient provided by light, radiofrequency radiation, or motion/vibration/thermal sources. These (micro)energy harvesting systems require efficient and reliable materials to convert the input environmental energy into an exploitable electrical output. In this context, among the most currently employed ceramics, zinc oxide (ZnO), both micro- and nano-structured, is gaining more and more importance in the design of energy harvesting devices because of its interesting features that comprise low cost, high piezoelectric characteristics, and ease of production, among others. The present work aims to summarize the current state-of-the-art on the use of ZnO micro- and nano-structures for the design and manufacturing of advanced piezoelectric devices and to provide the reader with some recent progress that may pave the way toward further advances in the forthcoming years.

Abstract Mindanao REACH, a collaboration among the Peace and Equity Foundation (PEF), Ramon Magsaysay Transformative Leadership Institute, and SELCO Foundation—supported by Ateneo de Davao University and the Mindanao Development Authority—aims to advance renewable energy for poverty reduction in Mindanao. As part of this initiative, an optimal energy system was designed for PEF’s social enterprise partner operating a coffee processing facility in Pangantucan, Bukidnon, which currently lacks electricity. Technical assessments, manual calculations, and HOMER Pro simulations evaluated six options: Grid ONLY; Grid + PV (26 kWp without battery); Grid + PV (26 kWp with 40 kWh battery); PV (26 kWp) + 40 kWh Battery + Backup Genset; PV (35 kWp) + 80 kWh Battery + Backup Genset; and Genset ONLY. Findings identified Option 4 (PV (26 kWp) + 40 kWh Battery + Backup Genset system) as the optimum energy system, considering the enterprise’s resources and lack of grid access. Although the grid-connected PV system without batteries achieved the highest ROI (33%), its larger capital cost and grid dependence made it less practical. Option 4 was therefore recommended for its balanced ₱2.7 million investment, enhanced energy security, and operational reliability. The findings highlight renewable energy’s critical role in rural enterprise sustainability.

In N2 photoreduction, photogenerated holes and electrons are involved in H2O photolysis for proton supply and the weakening of the N≡N triple bond for N2 activation, respectively. Rationally regulating the structure-activity relationship of these catalytic sites for available generation of charge carriers is crucial for optimizing N2-to-NH3 conversion efficiency. Herein, a robust photothermal catalyst carboxyl-enriched supramolecular (perylene tetracarboxylic acid, PTA) functionalized MIL-125(Ti)/MXene having dynamic proton extraction sites is designed for efficient N2 photoreduction. Among these, MIL-125(Ti), PTA, and Ti3C2 MXene are, respectively, responsible for N2 activation, reliable proton supply through interconversion between Brønsted acid and its conjugated base, and a photothermal response for accelerated reaction kinetics. The synergistic collaboration of these functionally distinct modules enhances light harvesting and responsiveness for dynamic multielectron/proton extraction, thereby facilitating feasible photothermal catalytic ammonia production. Remarkably high solar-to-ammonia conversion rates of 314.5-654.7 μmol g-1 h-1 are achieved under 100-500 mW cm-2 illumination. This work provides insights into the rational design of an efficient solar ammonia synthesis system.

This paper presents the design, construction, and experimental thermal evaluation of a modular solar heating system that integrates heat collection, storage, and emission into a single compact unit. The prototype consists of a flat-plate solar air collector directly coupled to a radiator-type thermal storage module. The central innovation lies in the use of paraffin as a phase change material (PCM), encapsulated in twelve finned aluminum tubes. This configuration enables the storage unit to function simultaneously as a passive heat exchanger, ensuring a uniform and sustained release of the accumulated energy. Experimental results, obtained under a solar irradiance of 950 W/m², showed that the air temperature at the collector outlet exceeded 70 °C. During the discharge phase, the indoor ambient temperature remained within the thermal comfort range (20.5 °C–23.6 °C) for up to six hours, maintaining a 3–4 °C temperature difference relative to the outdoor environment. The latent heat storage capacity of the PCM effectively mitigated indoor temperature fluctuations, contributing to stable comfort conditions. In conclusion, the proposed system represents a significant innovation in passive solar energy technology, integrating the functions of collector, accumulator, and radiator into a low-cost, easily replicable modular device. Its constructive simplicity and thermal efficiency position it as a viable and sustainable solution for residential heating in cold climates and rural or hard-to-reach areas with limited energy access.

This study presents the design, implementation, and experimental validation of an automatic solar street light system with Real-Time Clock (RTC)-based intensity control powered by Photovoltaic (PV) energy. Conventional solar street lights operate at fixed brightness throughout the night, resulting in unnecessary energy expenditure and accelerated battery degradation. The proposed system addresses this inefficiency by integrating a DS3231 RTC module with an Arduino Nano microcontroller to implement a five-level Pulse Width Modulation (PWM) dimming algorithm that adjusts LED illumination according to predefined time slots. An IRFZ44N MOSFET-based driver circuit delivers flicker-free brightness modulation at 980 Hz. A 20W polycrystalline PV panel, 10A PWM charge controller, and 12V/20Ah sealed lead-acid battery complete the energy subsystem. The system further incorporates battery voltage monitoring to automatically reduce load during cloudy periods, preventing deep discharge. Experimental results over a seven-day outdoor trial confirm an annual energy consumption of approximately 42 kWh —a 96% reduction over traditional 150W sodium vapor lighting and a 60% reduction over fixed-brightness solar LED alternatives. Battery backup exceeded two days under full-load conditions, and RTC accuracy was maintained within ±2 seconds over the trial period. The total prototype cost of ₹5,480 yields an estimated payback period of 22 months against a grid-connected fixture. The system is particularly suited for rural electrification, highway safety lighting, smart city applications, and emergency deployment scenarios.

In this research, design and performance analysis of standalone solar photovoltaic (SSPV) power system for health facility in Eket using PVSyst simulation software is presented. Specifically, standalone solar photovoltaic (SSPV) power system was designed and simulated with PVsyst for two scenarios for a hospital in Eket Akwa Ibom State. In the first scenario, the SSPV power system was design to eliminate loss off load without any alternative energy source other than the SSPV power system. In the second scenario, the SSPV power system was design to allow for some loss off load giving room for alternative back-up energy source other than the SSPV power system. The case study hospital has daily load demand of 455,754.00 kWh per day which approximates to a 24 hours a day energy consumption of an average load of 18989.75 Watt load. The annual total solar radiation of the site is 1717.2 kWh/m² while the annual mean for the ambient temperature is 24.9°C. The results shows that the scenario 1 has about 7.9% energy output above that of scenario 2. The unused energy in scenario 1 is about 26.5 % higher than that of scenario 2. The energy supply in scenario 2 is about 2% short of the load demand while the scenario 1 has no energy supply shortage. The energy supply shortage in scenario 1 cause the 2 %missing energy or loss of load with the attendant 179 hours of loss of load duration. In all, with detailed loss of load analysis up to hourly level, it is possible to make adequate prior arrangements for managing the expected loss of load incidences.