• High initial investment influences solar energy (SE) integration the most. • Cost of storage solution has the second most significant impacts on SE integration. • Incentives and subsidies have the third most significant impacts. • Uncertain return on investment has the fourth most significant impact. • Existing grid capacity has the lowest impact on SE integration. Renewable energy production is crucial for transitioning to a low-carbon economy, as there is a global push for sustainable energy sources. Integrating renewable energy, such as solar, presents economic challenges, including obtaining high efficiency and cost-effectiveness on a large scale. Solar energy (SE) is becoming a key component of national energy strategies to decrease CO 2 emissions and address rising energy demand and climate change. This article analyses the economic problems of integrating solar energy for sustainable development, including cost-effectiveness, efficiency, reliability, resilience and minimising transmission losses to reduce carbon emissions in the Global South. This research adopts an in-depth methodology, mostly literatures from 2018 to 2025, to analyse these economic challenges and their impacts on solar energy integration, plus a survey as a primary data source. 71 (67.6%) stakeholders agreed that high initial investment influence SE integration to a very large extent, 55 (52.4%) stakeholders agreed that cost of storage solutions affect SE integration to a very large extent, while 27 (25.7%) stakeholders believed that incentives and subsidies influence SE integration to a very large extent. The study shows that policies must prioritise constant investment in solar energy, giving incentives and subsidies and lowering the initial investment to encourage solar energy investments, integration, installations, reliability and sustainability. Recommendations are made to mitigate these challenges in SE integration in terms of initial investments, storage solutions costs, grid capacities, return on investment, transmission losses and incentives and subsidies to ensure solar energy reliability, affordability, efficiency, resilience and sustainability.

High absorption broadband solar energy device and thermal emitter based on titanium metamaterials

This study explores a pathway to decarbonising biofuel production by comparing hybrid renewable configurations, incorporating solar and geothermal energy, with a grid electricity scenario to identify the most environmentally sustainable approach. Five biodiesel production methods— alkaline-catalysed, acid-catalysed, two-step transesterification, electrolysis, and supercritical transesterification—were assessed for producing biodiesel from 1 kg of Chlorella vulgaris oil using the Australian Life Cycle Assessment Society (ALCAS) method, validated through ReCiPe 2016 Midpoint and Endpoint approaches. Among all methods, hybrid supercritical transesterification demonstrated the lowest environmental impact, achieving a global warming potential of 0.49 kg CO 2 eq, marking a 98.4 % reduction compared to grid-powered acid transesterification, the most emission-intensive process. Single score results further confirmed these benefits, showing substantial improvements across human health, ecosystem, and resource impact categories. Uncertainty analysis validated the consistency of these findings, demonstrating that the hybrid energy system outperformed grid electricity across all production methods, emphasising the critical role of renewable energy integration in reducing emissions and environmental burdens. Moreover, full adoption of the hybrid biodiesel system could contribute 6.4 % toward Australia's 2030 climate target, avoiding 2.9 million tons CO 2 eq annually. If implemented from 2025 to 2050, cumulative reductions could reach 72.5 million tons CO 2 eq, significantly supporting Australia's net-zero goals. • Carbon hotspot assessment was performed for microalgae-based biodiesel pathways. • A new geothermal and solar energy setup was assessed for biodiesel production. • Hybrid supercritical transesterification achieved the lowest environmental impacts. • Findings indicate a 2.9 Mt CO 2 eq annual emission reduction potential.

Techno-economic evaluation of an integrated solar still and solid oxide electrolysis cell system for hydrogen production from brine water

• Systematic tuning of alkylsilane chain length controls roughness and anti-soiling behavior. • Minimal fluorinated content enables sustainable, transparent coatings without loss of function. • Only 5% FAS is sufficient to achieve durable, high-performance anti-soiling coatings. Transparent, anti-soiling coatings are essential for mitigating dust-related efficiency losses in solar energy, but reliance on environmentally concerning fluoroalkylsilanes (FAS) remains a challenge. This study investigates a strategy to minimize FAS content by systematically blending alkylsilanes of varying chain lengths (C16, C8, C4), via a sol–gel process. We explore the fundamental interplay between surface energy and roughness across 14 formulations to establish design principles for sustainable coatings, using XPS, AFM, and SE measurements. Our key finding is a critical transition in the dominant anti-soiling mechanism at a surface energy of ∼20 mN/m. Above this threshold, performance is highly sensitive to roughness. Below it, low surface energy dominates, ensuring excellent performance even with higher roughness. This principle enables us to demonstrate that a minimal FAS content of just 5% is sufficient to cross this critical threshold and achieve durability and high performance, providing a pathway to drastically reduce fluorinated content without compromising functionality.

Hybrid solar-driven interfacial evaporation systems for water-energy nexus: recent advances in freshwater and energy sustainability

Multi-objective block form optimization for photovoltaic performance and heat island mitigation in plateau regions

Although territorial conflict is often cited as an inhibitor of renewable energy adoption, solar technologies have become an integral part of the Israeli-Palestinian conflict. This study examines how Israel, the Palestinian Authority, and Hamas have used solar energy as a tool to advance their respective security priorities in nationally contested territories, often at the expense of other economic or environmental considerations. Within the context of the ongoing conflict, solar energy projects serve to advance three main goals: (1) decentralizing electricity generation to prevent grid disruptions caused by aerial bombing campaigns in Gaza or by rocket attacks against Israel, (2) using off-grid rooftop PV panels in settlements or in divided urban environments such as East Jerusalem to prevent political misuse of a shared electricity grid, and (3) strategically positioning solar fields to ensure continuity and block rival expansion in contested territories such as Area B and C in the West Bank. Given these priorities, this study examines the factors that make the Israeli-Palestinian conflict more receptive to using solar panels as tools of national security compared to other territorial conflicts, and points to how these factors shape the type, location, financing and scale of the solar projects that each side of the conflict promotes.

The role of spatio-temporal satellite-derived products and numerical weather forecasts in data-driven intra-day solar forecasting

The current study employs dual numerical simulations of Sisko and Boger fluids on a disk. Two-way movement of nanofluid is induced by the expanding and shrinking movements of the disk. The applications of tetra-hybrid nanofluids are incorporated, which are used in electronic cooling devices, solar energy, electronic devices, heat exchangers, and lubrication. The combined effect of the electric and the Lorentz force is considered. The analysis of heat energy and mass diffusion is discussed with Joule heating, Brownian motion and thermo-pheresis. The effect of stagnation point motion is considered. The finite element approach is applied to obtain numerical solutions. The involvement of Boger fluid number (δ1) and electric field number (E0) enhance velocity field and the thickness of the momentum boundary layer. The temperature field increases by enhancing the Eckert number, electric field and thermo-pheresis parameters. Wall shear stress increases by enhancing the Lorentz force, while wall shear stress decreases when the Boger number decreases.

• Compilation of 14 ground-measured datasets with 2147 stations worldwide. • Proposal of a guideline for standardized quality control procedures. • Evaluation of availability, quality, and characteristics of solar radiation data. • Assessment of the significance of in-situ data for global solar potential analyses. • Application of time–frequency analysis to identify features in solar radiation. Accurate solar radiation data are fundamental for solar energy research. Reliable databases are essential to quantify their spatiotemporal variability. Although long-term ground-based radiometric measurements are considered the most reliable source of global horizontal irradiance data, they are prone to inaccuracies and often lacking in many regions. This study analyzes hourly global horizontal irradiance data from 14 datasets spanning more than 50 countries to assess data availability, data quality, and statistical as well as spatiotemporal characteristics. A comprehensive stepwise quality control procedure reviews existing and new quality tests to identify suspicious data points or entire implausible time series. After quality control, 1,618 out of 2,147 stations were retained: 289 with 2–5 years, 806 with 6–15 years, and 523 with more than 15 years of reliable data in the study period 1991–2020. This highlights that measurement sites with persistent long-term, high-quality data are scarce. While analyzing long-term changes and trends remains challenging, time–frequency analysis enables estimation of the time scales contributing most to variability at each location. Depending on the site, 47.2 % to 75.2 % of total variance is explained by deterministic cycles at the semi-daily, daily, and annual scales. The contribution of different time scales primarily depends on latitude, but is also influenced by topography and local conditions. Insights gained from quality-controlled ground-based data can be combined with global reanalysis and satellite data to better characterize spatiotemporal variability in global solar radiation and improve solar energy potential estimations from local to global scale.

Comparative analysis on the contributions of solar and wind energy to interfacial water evaporation using a 2D evaporator

Solar multi-vector energy systems (2019–2024): Technical performance, economic viability, and environmental benefits across climates

• Provide innovative experimental data of filling/emptying CO 2 tanks. • Comprehensive analysis of the dynamic behaviour of the CO 2 tanks. • Better understanding of CCES operating process with liquid storages. Energy storage systems are becoming a highly topical issue with the increasing integration of solar and wind energy into the electricity mix. Thermomechanical energy storage systems are attracting growing interest. They are based on thermodynamic cycles to store electricity under mechanical and/or heat energy. Compressed CO 2 energy storage systems are one emerging example. Despite numerous modelling studies, experimental investigations remain very limited. Existing experiments are restricted to gaseous CO 2 at low pressures. However, these systems are mostly investigated with storage tanks containing liquid or supercritical CO 2 . This study addresses this gap by presenting the first experimental results on the dynamic behaviour of reservoirs containing CO 2 in multiphase conditions (coexistence of liquid – gaseous CO 2 ) and reaching supercritical pressures. For that purpose, an experimental test rig based on conventional and commercial components was developed. It is composed of a 320 L low-pressure storage, a 240 L high-pressure storage and a 3 kW CO 2 pump. The mass flow rate ranges from 100 to 320 kg.h −1 , corresponding to charging times from 1 to 1.8 h (including a balancing step) with a maximal pressure of 22 MPa. The results indicate an inability to maintain a constant pressure during a tank emptying or filling due to temperature changes. During a discharge, the pressure in the high-pressure storage drops from 22 to around 3 MPa. As a consequence, this study highlights the possibility to balance the pressure after a discharge.

A systematic review of scale-up methods in prospective life cycle assessment of emerging solar energy technologies

Ultra wideband solar energy absorption device based on multi-layered Ti-InAs cylinder metasurface

• 3D ray tracing models optical performance of solar air heating concentrators. • Inverted absorber design minimises convective and radiative heat losses. • Smaller, elongated concentrators enhance efficiency and reduce material use. • Multiple smaller collectors outperform fewer large ones in building integration. • Design optimisation balances optical efficiency, size, and material requirement. The optical performance of inverted absorber asymmetric compound parabolic concentrators (IACPCs) for solar air heating applications is analysed. An inverted absorber concentrates incident solar energy on to a downward-facing transpired surface from which convective and radiative heat losses can be minimised. Three-dimensional ray tracing is used to model optical behaviour, simulating solar radiation pathways and interactions with reflective surfaces. The variations of optical efficiency and effective concentration ratio with reflector geometry, truncation and collector length are analysed. Findings indicate that smaller, elongated concentrators maximise optical performance and reduce material requirements when integrated over a fixed façade area. Design configurations that optimise aperture width optimise a trade-off between collector compactness and optical performance.

Determination of optimum parameters in photovoltaic panel with electrospray cooling

Promoting photon-generated carrier separation via a type-II Cu2O@MOF heterojunction cathode for photo-rechargeable zinc-ion batteries.

Agrivoltaics in India: A promising nexus of solar energy and agriculture for sustainable development