Search Results (1,086)

Locally available biomass resources offer a sustainable pathway for supporting traditional health practices at the community scale. This study designed, developed, and evaluated a biomass-fueled herbal steam generation system using Melaleuca leucadendra leaves for community-based therapeutic applications in the U-Tapao River Basin, Songkhla Province, Thailand. The system was developed based on appropriate technology principles aligned with the Bio–Circular–Green (BCG) economic model, integrating a biomass combustion stove with a steam generation unit. Performance was assessed using the Water Boiling Test (WBT) to measure thermal efficiency, boiling time, and steam generation capacity. Results showed that the developed system significantly improved thermal efficiency and reduced boiling time compared with traditional methods (p < 0.01), attributable to enhanced combustion characteristics and heat transfer efficiency. Field trials across two herbal steam room configurations confirmed stable therapeutic temperatures of approximately 40 °C sustained over 30–35 min sessions. The system is technically feasible, energy-efficient, and practically viable for community-scale deployment. This work demonstrates that integrating renewable biomass energy with traditional herbal therapy can provide a replicable, sustainable model for local resource utilization and community-based economic development. Full article

Progressive climate change and growing energy demand are increasing the importance of renewable energy sources, including hydropower, particularly in regions with favourable hydrological conditions. This study aims to assess development characteristics and the feasibility of determining the hydropower potential of the Radunia River in northern Poland, taking environmental conditions into account. The study employed a hydrological–energy approach based on long-term flow data analysis, the section method, and calculations of water flow power, supplemented by analyses of flow duration curves and differential integral curves. The Radunia River is an example of a lowland watercourse with a relatively high hydroelectric potential for northern Poland, resulting from a favourable combination of hydrological and environmental factors. The results indicate a marked variation in hydropower potential along the river’s course, with the potential concentrated in the middle and lower reaches, where the highest flows and gradients occur. The calculated total potential is approximately 7.07 MW, and annual energy production exceeds 61.9 GWh, with actual production in the existing cascade system of power stations being close to the theoretical values. At the same time, accounting for environmental constraints results in a slight reduction in potential (less than 1%), underscoring the importance of a sustainable approach. The conclusions indicate that the Radunia River is an example of the effective use of water resources, and that the further development of hydropower should be based on the modernisation of existing infrastructure using new environmental technologies, whilst complying with environmental protection requirements. Full article

Ensuring adequate water supply on islands is challenging due to high costs, limited resources, and energy constraints. This study examines the potential of meeting the water supply demands of the island of Kos through renewable-energy-powered desalination, supported by battery storage systems and the utilization of the under-construction Mia Dam. Energy management prioritizes domestic demand, with surplus energy stored or used for desalination, and deficits covered by battery storage and reservoirs. The results estimate water costs per cubic meter, allowing the assessment of the economic viability of the scenarios and the optimal strategic coverage of the island’s water needs. Full article

The growing demand for efficient and sustainable materials for air purification has stimulated interest in activated carbons derived from renewable biomass resources. In this study, activated carbons were prepared from Rice Husk, Wheat Straw, Sawdust, and Walnut shells and systematically investigated as sorbents for toxic gases and volatile organic compounds. The materials were characterized using nitrogen and water vapor sorption isotherms, scanning electron microscopy, thermogravimetric analysis, Fourier-transform infrared spectroscopy, energy-dispersive X-ray and XPS analysis to evaluate their textural properties, morphology, thermal stability, and surface chemistry. The results showed that the precursor type strongly influences the pore structure and functional group composition of the activated carbons. Wheat straw and Rice Husk-derived activated carbons exhibited the highest total pore volume and a well-developed porous structure, together with a high content of oxygen- and silicon-containing elements. Gas breakthrough experiments with different probes showed that Wheat Straw-derived activated carbon excels in non-polar VOC—cyclohexane removal due to its highly microporous structure. In contrast, Rice Husk-derived activated carbon displays strong affinity toward inorganic gases such as NH₃ and, after urea modification, achieves enhanced performance for SO₂. These results underscore the versatility and practical applicability of carbon materials obtained from plant residues. Full article

This paper evaluates the potential for green hydrogen production in Tunisia using nearly 3 GW of renewable electricity distributed across four strategically selected sites: Haouaria, Zriba, Sbikha, and Feriana. These locations were chosen for their proximity to the Trans-Mediterranean (TransMed) natural gas pipeline linking Algeria to Italy, as well as their strong but underexploited solar and wind energy resources. Each site was optimized according to land availability and renewable energy potential: Haouaria is wind-dominant, Zriba employs a hybrid solar-wind configuration, Sbikha focuses on solar, and Feriana integrates both solar and wind over a large area. The analysis reveals a total green hydrogen production capacity supported by approximately 3.1 GW of installed renewable power, with a base-case LCOH ranging from $1.21 to $2.05 per kilogram. El Haouaria emerges as the most cost-effective site due to its highly favorable wind conditions, while the sensitivity analysis shows that LCOH can reach up to approximately $3.8 per kilogram under higher CAPEX assumptions. The findings underscore the viability of a multi-site development strategy and highlight northern Tunisia’s comparative advantage for low-cost green hydrogen production, thanks to its superior resource mix, existing infrastructure, and better water availability relative to Tunisia’s southern regions. Full article

The purpose of this paper is to present a techno-economic methodology for assessing the economic sustainability of offshore wind energy development within the Romanian exclusive economic zone (EEZ) of the Black Sea. The methodology illustrates nine key cases in this area that are grouped into three classes, each positioned at a greater distance from the Romanian coast and thus generating different environments given the water depth and wind climate. The data used for the analysis came from the ERA5 database and covered a 20-year span. Six types of wind turbines with capacities ranging from 5 to 9.5 MW were considered. In determining the levelized cost of energy (LCOE), the turbine with the highest production was considered, which turned out to be the Seimens Gamesa 8 MW, and for the economic model, the components related to both capital and operating costs were considered. Following the analysis, it was observed that the B2 site presents the best wind resources, also leading to the highest energy production of x. Regarding the LCOE analysis, values between 66.86 EUR/MWh and 87.39 EUR/MWh were obtained if the entire energy production is considered. Following the simulation with losses, the LCOE increases to values between 92.19 EUR/MWh and 121.85 EUR/MWh. Finally, an optimization calculation was also performed for the site with the highest LCOE considering another foundation time, after which the LCOE decreased to approximately 111.09 EUR/MWh, if we refer to energy production with losses. The results contribute to the economic sustainability evaluation of offshore wind projects in the Romanian Black Sea and influence future investment plans, sustainable energy planning, and renewable energy infrastructure development. Full article

This integrative critical review examines how biomass and bioenergy can contribute to energy diversification while accounting for constraints related to climate mitigation, energy security, resource availability, and technology readiness. The review combines a targeted literature synthesis with expert-informed insights from the international seminar Energy Transition and Biofuels held at the Federal University of Itajubá in October 2025. The seminar and COP30-related discussions were used as contextual and conceptual inputs, while peer-reviewed literature, policy documents, and technical reports provided the evidentiary basis for the analysis. The manuscript evaluates biomass and biofuels utilization, refinery integration, sustainable aviation fuels, biochar, BECCS, hydrogen synergies, life-cycle assessment, artificial intelligence, and logistics. The synthesis indicates that biomass is not a universal substitute for fossil fuels. Still, it has distinctive value in applications requiring renewable carbon, dispatchable energy, process heat, liquid fuels, carbon removal, and compatibility with existing infrastructure. The analysis also shows that these contributions are contingent on feedstock governance, land and water safeguards, logistics, fertilizer inputs, technology maturity, and verified life-cycle performance. The food–fuel discussion is therefore reframed as a context-specific problem of land-use, access, productivity, and governance rather than a simple competition between energy and food production. The study concludes that bioenergy can most credibly support the energy transition when deployed through differentiated pathways tailored to regional resources, sustainability constraints, and sector-specific decarbonization requirements. Full article

This work evaluates the transition from grey to green hydrogen in the Haber–Bosch process through a case study of the Fertial ammonia plant. An integrated assessment per ton of NH₃ was conducted using coupled process simulation with system-level mass, energy, and emission accounting, which link the electrolyser dynamics with ammonia loop operation under variable renewable conditions. The results show an electrical demand of 8.9 MWh/t NH₃ and significant water consumption potential of 27–34 m³/t NH₃. Compared with grey ammonia produced via SMR hydrogen (3.65–4.63 t CO₂/t NH₃), renewable electrolysis reduces total emissions by up to 64% and fossil resource use by approximately 71% (case of 100% PV), depending on electricity carbon intensity. While renewable electricity enables ammonia decarbonization, high water consumption potential represents a challenge. Additionally, hydrogen purity fluctuations and intermittent electrolyser output affect loop conversion and process stability, highlighting the need for heat integration and storage strategies to maintain steady operation. Full article

Viscosity reducers are essential additives for water-based drilling fluids (WBDFs), serving to counteract the rheological degradation induced by the high-temperature and high-salinity conditions commonly encountered in deep and ultra-deep well drilling. This paper systematically reviews the research progress in this field, categorizing viscosity reducers into three major systems: modified natural materials, industrial waste utilization, and synthetic polymers. Modified natural material viscosity reducers, derived from renewable materials such as lignin and humic acid via chemical modification, are environmentally friendly products. The preparation of viscosity reducers from industrial wastes realizes both resource recycling and economic benefits. Synthetic polymer viscosity reducers, incorporated with functional monomers such as sulfonic and carboxylic groups, achieve high performance with temperature resistance exceeding 220 °C as well as excellent salt and calcium tolerance via rational molecular design, and represent the current mainstream research direction in the field. This paper provides an in-depth analysis of the action mechanisms of various viscosity reducers, summarizes the performance characteristics, synthesis methods and application status, and identifies challenges in structure–property relationship elucidation, extreme working condition adaptability, and technology transfer efficiency. Finally, future development trends are discussed, with emphasis on precision molecular design, ultimate performance requirements for ultra-deep wells, environmentally sustainable approaches, and the establishment of standardized evaluation protocols. This review aims to provide both theoretical insights and practical guidance to support the efficient development of deep oil and gas resources. Full article

Lithium has become one of the key raw materials for the energy transition due to the central role of lithium-ion batteries in electromobility, energy storage, and the integration of renewable energy sources. However, the rapid increase in demand reveals growing environmental, social, geopolitical, and market tensions. The aim of the paper is a critical synthesis of global lithium utilization from the perspective of challenges, technological innovations, and integrative strategies supporting a more sustainable material-energy system. A broad, systematic literature review covering the entire value chain was applied: resources, extraction, processing, end-use applications, second life of batteries, recycling, and governance. The analysis shows that the strategic importance of lithium arises from the increasing demand pressure from electric vehicles and stationary storage, while the sustainability of the current model is constrained by supply concentration, uneven control over downstream stages, the water-carbon footprint of extraction and processing, social conflicts, and incomplete integration of secondary loops. At the same time, innovations such as direct lithium extraction (DLE), recovery from geothermal brines, design for recycling, second life, and battery passports can partially alleviate these tensions, but they do not eliminate the need for primary supply in the short term. The conclusion of the work is that sustainable global lithium utilization requires simultaneous diversification of sources, development of circular value chains, and multi-level governance integrating resource security, environmental efficiency, and social legitimacy. Full article

The increasing demand for lithium (Li), cobalt (Co), and rare earth elements (REEs) driven by battery technologies, electrification and renewable energy systems has intensified the interest in recovery pathways as an alternative to conventional mining. High-salinity mine waters—including lithium brines, geothermal fluids, and metallurgical effluents—represent both an environmental liability and a significant secondary resource for metal recovery. However, extreme ionic strength, complex metal speciation, and strong competition from major ions severely limit the efficiency and selectivity of traditional extraction technologies. Microalgae and cyanobacteria are promising biological agents for metal recovery via biosorption, bioaccumulation, and extracellular polymeric substance (EPS)-mediated binding, especially in saline and hypersaline systems. This review synthesises current knowledge on microalgal-based recovery of Li, Co, and REEs from high-salinity waters, emphasising co-design principles that integrate strain physiology, their adaptation to the extreme operating conditions, water chemistry, and process engineering. Halotolerant and extremophilic taxa—Nannochloropsis oceanica, Galdieria sulphuraria, and Synechococcus elongatus—are examined as representative models for complementary metal-binding mechanisms and operational niches. Limitations such as weak affinity for lithium, competitive ion suppression, desorption inefficiencies, and scale-up challenges are discussed. Emerging strategies such as modular multi-strain systems, hybrid bio-physicochemical platforms, and biomass valorisation are also addressed. The review concludes that microalgal systems, when co-designed for selectivity and resilience, can contribute to the strategic recovery of critical materials that align with EU, UK and US policies. Full article

We propose a quantitative, spatially explicit framework for assessing local self-sufficiency and resilience within the Water–Energy–Food (WEF) Nexus. The methodology introduces normalized, per capita indicators that quantify the degree of dependence on local versus external resources, explicitly incorporating physical availability, renewability, energy requirements, infrastructure, and land-use constraints. In contrast to conventional composite indices, the proposed framework adopts a non-compensatory structure, whereby deficiencies in one sector cannot be offset by surpluses in another, reflecting the physical constraints of the nexus. Indicator values range from 0 (complete dependence on external resources) to 1 (full local self-sufficiency) and are formulated dynamically, enabling comparison across existing conditions and alternative infrastructural or policy scenarios. The framework is applied as a proof of concept to a small rural settlement in North Euboea, Greece. The results indicate substantial potential for food and renewable energy self-sufficiency under optimized infrastructure configurations, while also revealing critical vulnerabilities associated with groundwater-dependent water supply and seasonal energy imbalances. The analysis further demonstrates how spatial proximity, energy–water coupling, and land-use competition jointly constrain achievable self-sufficiency levels, highlighting trade-offs that are often overlooked in sectoral or purely volumetric assessments. By explicitly linking resource flows with spatial proximity and infrastructural choices, the proposed indicators provide a robust and transparent tool for resilience-oriented planning under conditions of climatic, environmental, and systemic uncertainty. Full article

Groundwater flow is an integral part of the Earth’s water cycle and plays a key role in assessing groundwater resource potential, characterizing the upper limit of possible groundwater withdrawal over a long period without depletion. The objective of this study is a comprehensive regional assessment of groundwater flow and the natural and predicted resources of fresh and low-mineralized groundwater in Southern and Western Kazakhstan. This assessment is based on an analysis of hydrogeological conditions and water balance, taking into account climate variability and anthropogenic load, to justify sustainable water resources management in arid territories. This article provides a regional assessment and mapping of groundwater flow, taking into account climate and anthropogenic changes in Kazakhstan, to refine the predicted resources of fresh and low-mineralized groundwater. The basin balance calculation results indicate that in arid and semi-arid regions, the decline in groundwater recharge by the 2050s will generally not exceed 10%. The average layer of groundwater flow of renewable groundwater resources in the Kazakhstan part of the Zhaiyk-Caspian water management basin (WMB) is estimated at 33.4 mm/year, and the average modulus of groundwater flow is 1.06 L/s per 1 km². The average layer of groundwater flow of renewable groundwater resources in the Kazakhstan part of the Aral-Surdarya water management basin (WMB) is estimated at 14.8 mm/year, and the average modulus of groundwater flow is 0.47 L/s per 1 km². The average layer of groundwater flow of renewable groundwater resources in the Kazakhstan part of the Shu-Talas water management basin (WMB) is estimated at 26.5 mm/year, and the average modulus of groundwater flow is 0.84 L/s per 1 km². For mountainous and folded regions, the average layer of groundwater flow of renewable groundwater resources in the Balkhash-Alakol water management basin (WMB) system is estimated at 70.7 mm/year, and the average modulus of groundwater flow is 2.24 L/s per 1 km². For intermontane and foothill basins, the average layer of groundwater flow of renewable groundwater resources in the Balkhash-Alakol water management basin (WMB) is estimated at 54.3 mm/year, and the average modulus of groundwater flow is 1.72 L/s per km². Full article

Across human history, water has sustained communities while also shaping religious imagination as a symbol of life, danger, purification, and renewal. This review examines how water acquires religious meaning through symbolic associations, ritual uses, theological interpretations, sacred landscapes, and material water infrastructures across more than five millennia, drawing on examples from ancient civilizations, long-standing Asian traditions, Indigenous religions of the Americas and the Caribbean, and the three major Abrahamic religions. The study explores how rivers, springs, rain, floods, wells, sacred basins, and ritual waters have been understood as signs of creation, purification, fertility, healing, divine presence, destruction, and renewal, while also remaining part of everyday practices of settlement, agriculture, health, and communal life. The comparative analysis highlights recurring patterns and cultural differences. In some traditions, water appears as a primordial substance from which life emerges; in others, it functions as a medium of moral cleansing, ritual preparation, communal prayer, or sacred geography. The study argues that the religious meaning of water is best understood through the interaction of four closely related dimensions: symbolic interpretation, ritual practice, sacred or culturally charged landscapes, and material water infrastructures. By bringing these dimensions together, the article uses the concept of hydraulic heritage to connect religious water symbolism with sacred basins, wells, springs, hammams, monastic water systems, irrigation rituals, and other inherited water-related landscapes and practices. These connections offer a culturally grounded perspective for contemporary discussions on environmental ethics, water protection, and societies’ responsibility toward natural resources. Full article

Climate change is expected to significantly affect hydrological processes in high-Andean basins, where water availability depends strongly on seasonal precipitation and groundwater recharge. This study evaluates future impacts on runoff, groundwater recharge, renewable water resources, and water stress in the Coata River basin (Lake Titicaca watershed, Peru) using the SWAT model forced with CMIP5 climate projections (MPI-ESM-MR and ACCESS1-0 under RCP 4.5 and RCP 8.5 for the period 2025–2100). Model calibration showed satisfactory performance (${\mathrm{R}}^2$ = 0.86; NSE > 0.80). Results indicate a pronounced reduction in groundwater recharge, strong variability in runoff, and persistently high water stress across scenarios. Although some projections show increases in runoff, reduced infiltration and subsurface storage limit effective water availability. Renewable water resources exhibit contrasting responses depending on the scenario, with both increases and decreases relative to historical conditions, but with greater variability overall. These findings highlight the high sensitivity of the Coata River basin to climate variability and emphasize the need to incorporate climate projections into water management strategies, including recharge zone protection, improved storage capacity, and more efficient water use. Full article