Search Results (366)

When a fuel briquette is pressed using solar electricity in summer and burned for heating in winter, the briquette functions as a seasonal energy store—without batteries, self-discharge, or capital investment in storage infrastructure. This paper quantifies such “indirect energy storage” at an operating briquette production facility in Sumy, Ukraine, using 2024 operational data from a 34 kW hybrid solar power plant integrated into the production process without battery storage under continental climate conditions (50°55′ N) and full-scale military conflict. The objective was to determine the contribution of the solar power plant (SPP) to energy supply, analyse the structure of electricity consumption, and quantify the mechanism of indirect accumulation of renewable energy through transformation into solid biofuels. The study tested two hypotheses: (H1) that integration of a solar power plant into industrial daytime operation (6:00–22:00) achieves a self-consumption rate close to 100%, displacing grid electricity without curtailment or storage losses; and (H2) that the solar fraction embedded in produced briquettes constitutes a quantifiable mechanism of indirect seasonal energy storage despite a temporal mismatch between solar peaks (summer) and product demand (winter). Methods included statistical analysis of monthly and intraday operational data; Pearson correlation analysis between solar generation and production cycles; energy audit of production processes; decomposition of specific consumption into pressing and packaging components; and a simple economic assessment (NPV, IRR, LCOE, payback) with sensitivity analysis. Annual production reached 1222.975 t of briquettes. Total specific electricity consumption (including two short packaging campaigns in June and July only) was 141.3 ± 12.6 kWh/t (CV = 8.9%). After deducting 4962 kWh of dedicated packaging electricity (2.9% of annual consumption), the specific consumption for briquette pressing alone was 136.7 ± 5.0 kWh/t (CV = 3.7%)—within the European benchmark range of 80–150 kWh/t for wood densification, with tight monthly variation indicating a stable, well-tuned pressing operation throughout the year. The SPP supplied 18.3% of total annual electricity, peaking at 33.06% in May and averaging 29.95% from March to August. Intraday analysis of 530 five-minute intervals confirmed a 100% self-consumption rate across all seasons (H1 supported). A total of 223.4 t of briquettes containing accumulated solar energy were produced during the spring–summer period. A weak negative correlation (r = −0.28) between monthly SPP generation and briquette production was observed but did not reach statistical significance (p = 0.385); this descriptive—rather than causal—relationship is consistent with the expected temporal shift between summer surpluses and winter demand, and is itself a signature of indirect rather than direct energy coupling (H2 supported in a descriptive sense). The compound efficiency along the solar-to-stored-fuel chain was estimated at approximately 68%, providing a quantitative indicator for the indirect-storage concept. Economic analysis yielded a simple payback period of about 3 years, NPV (20 yr, 12%) ≈ 1.15 million UAH, IRR ≈ 33%, and LCOE ≈ 3.28 UAH/kWh—61% below the prevailing industrial tariff of 8.45 UAH/kWh—with sensitivity analysis showing positive NPV across ±20% variation in electricity price and ±15% in CAPEX. To the best of the authors’ knowledge, this is the first empirical quantification of biomass-solar integration as a seasonal energy buffer operating without battery storage. The solar energy accumulated in briquettes is sufficient to heat 56–74 households for a full winter season. Regional scaling of the present configuration—under explicit assumptions of comparable facility sizes and operating regimes—could in principle provide fuel for 15,000–20,000 households (8–12% of regional heating needs during energy crises). These findings are directly relevant to post-conflict energy recovery and to regions where attacks on energy infrastructure have left solid biofuels as the primary available heating source. Full article

Understanding moose calving space use in disturbed landscapes can inform forestry and wildlife management. GPS collars were deployed on 89 female moose between 2018 and 2022 in the Cree traditional territory of Eeyou Istchee in northern Quebec, Canada. We compared space use and fidelity during a 7-day period following video- and movement-estimated parturition dates to equivalent period measures in late winter and summer. We also evaluated calving site selection comparing the use and availability of terrain, land cover, road density, and fire and forestry disturbance. Female space use during the 7-day post-calving period was confined to 0.04 km², comparable to 7-day space use in winter, but smaller than 7-day space use in summer. Females observed calving across multiple seasons expressed low calving site fidelity, calving a median distance of 4.00 km from previously used sites, which was lower than summer range fidelity and similar to winter range fidelity. No differences were observed in calving site space use and fidelity between a southern forestry-affected area and a northern fire-affected area or with the extent of disturbance. Female moose exhibited individual variability in calving site selection, with overall preferences for elevated areas with mixed-wood or broadleaf forests and low road densities. Females were not observed calving in areas disturbed by forestry or fires within the last year, but some females preferentially selected 10- to 15-year-old burns as calving sites. Because female moose used and remained highly localized around dispersed, annually variable calving sites, protection of moose calving habitat should move beyond the specific sites where moose are observed calving to the general habitats preferentially used by moose during this critical life history stage. Full article

The black carbon (BC) emission resulting from human activity comes mainly from fossil fuels and solid biomass burning, as well as transport fuels due to incomplete combustion. The biggest sources of BC pollution are currently diesel transport and domestic heating appliances burning solid fossil fuels or biomass. Firewood and pellet fuels were used for this BC research. The study used four domestic heating appliances using wood and agricultural waste pellets, as well as several types of firewood. The tests used a gravimetric particulate analysis method to determine the total amount of particulate matter. In further physical and chemical analyses, the emissions are broken down into components, i.e., substances of known composition that can be separated from the sample and weighed. In our study, the BC emissions varied from 0 to 120 mg/MJ depending on the type of boiler (automatic or manual), the combustion mode (based on oxygen supply), and the type of fuel. Emissions varied from 0–8 mg/MJ in a modern pellet-fired and automatically-controlled boiler, and from 1–25 mg/MJ in a wood-fired water heating boiler, with the highest emissions found for softwood (spruce). In the pellet stove with automatic feeding and control, BC emissions varied between 1 and 120 mg/MJ, with the highest emissions detected for wood pellets, and in the wood-burning fireplace, the emissions varied between 6 and 80 mg/MJ, with the highest emissions detected for birch firewood. Full article

Brazil is the main coffee producer in the world. However, the impacts of climate change driven by greenhouse gas (GHG) emissions pose a major challenge for agriculture in tropical regions. This study established a GHG inventory of coffee production on farms in southern Minas Gerais, Brazil, over a two-year period, adopting a cradle-to-farm-gate approach. It considered scopes 1 and 2 emissions from on-farm activities. The emission inventories were based on Intergovernmental Panel on Climate Change (IPCC) methodologies adapted for Brazilian conditions. The emissions were categorized in direct and biogenic and by area (in hectares) and production (kg of coffee). Electricity consumption, fossil fuel use, wood burning and fertilizer application were considered. Direct total emissions ranged from 2617 to 6211 t CO₂e, 2.67 to 3.81 t CO₂e ha⁻¹, and from 1.52 to 4.59 kg CO₂e kg⁻¹ of coffee. Biogenic emissions ranged from 336 to 4955 t CO₂e, 0.28 to 2.95 t CO₂e ha⁻¹, and from 0.32 to 2.21 kg CO₂e kg⁻¹ of coffee. Urea-based nitrogen fertilizers were the main source of direct emission and wood burning was the main source of biogenic emission. Management practices such as applying non-urea-based fertilizers, adjusting nitrogen rates according to soil analyses and manual harvesting contributed to mitigating GHG emissions. The observed emission intensities were consistent with other reported values for Brazilian coffee production. Further reductions may be achieved by adopting agroforestry systems, increasing coffee straw retention in the soil and replacing urea with alternative nitrogen sources, including slow-release fertilizers and urease-inhibitor technologies. Full article

In recent years, the frequency of forest fires has increased in many regions worldwide, with many fires developing rapidly and affecting large areas. Such fires lead to profound changes in ecosystem structure and functioning. Diptera play an important role in temperate European forests and, due to their high mobility, are among the first insect groups to colonize burned areas. However, many aspects of post-fire colonization by flying insects remain insufficiently studied. The study was conducted in the Republic of Mordovia (central European Russia) during the first year after the fires of 2021. Insects were collected using beer traps baited with beer and sugar. Sampling was carried out from April to October 2022 at 11 plots. The plots differed in fire intensity, distance from the 2021 fire edge, and the degree of vegetation recovery following the fires of 2010 and 2021. In total, 44 Diptera families were identified, comprising more than 36,000 specimens. Several families were represented by more than 1000 individuals in traps, including Anthomyiidae, Bibionidae, Chloropidae, Drosophilidae, Milichiidae, Muscidae, Polleniidae, Sciaridae, and Tachinidae. The lowest numbers of individuals and families were recorded at plots located farthest from the fire boundary, i.e., at the greatest distance from unburned areas. We found that Diptera abundance in traps correlated significantly with percentage of wood debris on a plot (r = 0.71, p < 0.05), and number of herb species per plot (r = 0.76, p < 0.01). The lowest values of biodiversity indices (Shannon, Simpson, Margalef, Pielou, and Berger–Parker indices) were recorded at a plot located 1 km inside the burned area. The highest values of these indices were observed at plots situated along the fire boundary. At completely burned plots located far from the fire edge, Diptera abundance dynamics were heterogeneous. Seasonal activity of Diptera at other plots was characterized by a slight increase in abundance in May, followed by a decrease by July, and a subsequent gradual increase from August to October. Full article

Levoglucosan (LG), a tracer of biomass-burning air pollution, was measured in PM₁₀ particulate matter during a year-long study at an urban background site in Zagreb, Croatia. It is known that the atmospheric lifetime of LG is not constant and undergoes degradation through reactions with hydroxyl radicals, ozone, photooxidation, etc. In this study, daily variations in LG were examined and evaluated in relation to NO₂, O₃, and meteorological conditions, including temperature, relative humidity, solar irradiance, UV index, and wind characteristics. The annual mean PM₁₀ concentration was 22 µg m⁻³, while LG average was 0.312 µg m⁻³, both exhibiting pronounced seasonal variability. Elevated LG levels occurred during winter and autumn, consistent with residential wood combustion and stable atmospheric conditions, whereas markedly lower concentrations were observed in spring and summer. Moderate correlations of LG with PM₁₀ and NO₂ indicate contributions from combustion sources, while weak wind speeds and limited dispersion favored pollutant accumulation. In contrast, significant negative relationships were found between LG and ozone, temperature, and UV index. The results revealed non-linear behavior and an exponential decrease in LG with increasing oxidant levels, suggesting pseudo–first-order degradation driven by enhanced photochemical activity and hydroxyl radical formation. These findings highlight the importance of considering both emission patterns and atmospheric processing when using levoglucosan as a tracer of biomass burning in urban environments. Full article

The use of wood chips in the heating sector leads to the generation of combustion waste with variable properties, which poses challenges for their rational management. To determine the variability of combustion waste, samples were collected over a 13-week period during the heating season, as weekly aggregate samples from a biomass bioheating plant burning wood chips. Three waste fractions were obtained for analysis: residue from the grate (B1), dust from the dust collector (B2), and boiler dust (B3). Dry matter (DM), reaction (pH_KCl), electrolytic conductivity (EC), content of total carbon (TC), total nitrogen (TN), macronutrients (P, K, Mg, Ca, Na), and heavy metals (Fe, Mn, Zn, Cu, Pb, Cd, Cr, Co, Ni) were determined in the collected samples. All waste fractions were characterized by an alkaline reaction. Regardless of the waste fraction, the macronutrient content was dominated by Ca, K, and Mg, with significantly lower levels of P and Na. Among heavy metals, Fe, Mn, and Zn had the highest recorded contents, and the lowest by far was Cd. With respect to sampling dates, the least diversified chemical composition was observed for B1 samples, more diversified for B2, and the most diversified for B3. In turn, regardless of the waste fraction, the most diversified results were observed for Cd and Pb, and the least for pH, DM, and TC. Concerning environmental management of combustion waste, fraction B1 deserves attention, as it was characterized by the richest chemical composition (TN, P, K, Mg, Ca, Na, Mn, Zn, Cu, Co, Ni). However, due to the highest content of undesirable heavy metals (Pb, Cd) and the highest salinity, it requires constant monitoring of the composition. Full article

Increasing global demand for animal-based protein has created a critical environmental management challenge regarding manure accumulation in intensive livestock production. Gasification offers a sustainable solution by converting organic residues into renewable synthetic gas (syngas) and carbon-rich biochar. This study systematically evaluated the performance of three major types of animal waste—dairy manure, poultry litter, and swine manure—against a lignocellulosic control (wood veneer waste) in a top-lit updraft (TLUD) gasifier. Three airflow rates (10, 15, and 20 L min⁻¹) were studied. The results indicated that increasing airflow significantly elevated the gasifier flame front temperatures, with poultry litter achieving the highest peak temperature (825.5 °C), followed by swine manure and dairy manure (753.7 and 727.0 °C, respectively) at 20 L min⁻¹ airflow. While dairy manure exhibited the fastest linear burning rate (25.7 mm/min), poultry litter demonstrated the highest mass consumption rate (32.8 g/min). Feedstock chemistry drove distinct reaction pathways in syngas composition. Poultry litter emerged as the superior feedstock for H₂ production, achieving a peak H₂ concentration of 10.78% at 20 L min⁻¹, which attributed to a synergistic combination of outstanding temperature, moisture content and catalytic alkali metals that promoted steam reforming and water–gas shift reactions. CO production was dominated by wood veneer (17.6%), which was driven by the dominance of elemental carbon and fixed solid (FS) content that favored partial oxidation and a Boudouard reaction. These findings suggest that while airflow regulates thermal kinetics, the specific energy profile of the produced syngas is fundamentally determined by the physiochemical properties of the biomass precursor. Full article

Inonotus hispidus is an important medicinal and edible fungus within the “Sanghuang” category, featuring a broad host range and rapid fruiting body growth. However, its wild resources are currently threatened by overharvesting. Simultaneously, large-scale jujube (Ziziphus jujuba) cultivation generates substantial pruning waste, often burned. This study explored the feasibility of using jujube wood as a cultivation substrate for I. hispidus. Three I. hispidus strains, Z1, Z2, and ZL, were cultivated on substrates with varying proportions of jujube wood replacing cottonseed hulls. The biological efficiency, nutritional components, active compounds, and free amino acid profiles of the resulting fruiting bodies were analyzed. Non-targeted metabolomics was used to investigate global metabolic changes. Results indicated that all strains successfully colonized the jujube-based substrates and produced fruiting bodies. Strain ZL exhibited the highest biological efficiency and the shortest growth period on the 48% jujube wood substrate, while others showed significantly increased triterpenoids and flavonoids content. Metabolomic analysis revealed substrate-dependent and strain-specific alterations in metabolic pathways, particularly in amino acid biosynthesis, the TCA cycle, and secondary metabolism. This study confirms jujube wood as a viable alternative substrate for the edible (ZL) and medicinal (Z1, Z2) cultivation of I. hispidus, providing a sustainable production method while establishing a valuable utilization pathway for jujube wood waste. Full article

Faced with the depletion of fossil resources and the need to promote a circular economy, lignocellulosic biomass represents a solution for energy transition and bioeconomy. However, wood sawdust, which contains bioactive compounds (secondary metabolites), is often burned in the open by many sawmills. This study aims to valorize Framiré wood sawdust by extracting its secondary metabolites through maceration and infusion, then converting the depleted residue into combustible briquettes. The yellowness index of the extracts ranged from 73.490 ± 0.021 (maceration) to 81.720 ± 0.014 (infusion). The total phenolic content varied from 0.097 ± 0.001 to 0.63 ± 0.049 gGAE/100 g dry matter for maceration and infusion, respectively. The extraction of bioactive compounds did not significantly affect the energy or mechanical properties of the fuels. Their higher heating value ranged from 26,153 ± 92 to 26,201 ± 90 kJ/kg for fuels with and without secondary metabolites, respectively. The Shock Resistance Index ranged from 139.33 ± 7.51% (without metabolites) to 153.00 ± 5.20% (with metabolites). A significant difference was observed in the specific consumption of the fuels, decreasing from 1.400 ± 0.100 to 0.861 ± 0.001 kg/L for fuels without and with secondary metabolites, respectively. These results open promising prospects, particularly for the use of Framiré extracts to develop flame-retardant products for wood and its derivatives. Full article

Widespread residential wood burning in southern Chile combined with cold climate conditions cause severe episodes of particulate matter (PM_2.5 and PM₁₀) pollution. In this study, we used logistic regression to predict daily exceedances of fine (PM_2.5) and coarse (PM₁₀) particulate levels at multiple urban sites, assessing model performance under different air quality standards. Results showed a clear latitudinal gradient in air pollution, with communities further south experiencing significantly higher PM levels and more frequent threshold exceedances, likely due to higher per capita firewood use and cooler temperatures. The logistic models achieved their best predictive accuracy under the strictest European (ESP) air quality standards (F1-scores up to ~0.72 for PM₁₀ and ~0.59 for PM_2.5), while Chile’s national (NCh) thresholds significantly underestimated pollution events. Additionally, annual per capita wood energy consumption in the far south was several times higher than in central Chile, contributing to disproportionately high emissions. These findings highlight the need to adopt more protective air quality standards and reduce wood-fueled emissions to improve early warning systems and decrease particulate exposure in southern Chile. Full article

The aviation industry needs to develop sustainable, fire-safe cabin interior materials. Although wood is eco-friendly, its high flammability makes it challenging to meet flame retardant standards. Enhancing wood fire safety requires the creation of an environmentally friendly and flame retardant coating. In this study, a new type of intumescent flame retardant (IFR) coating was applied to the wood surface using the layer-by-layer (LBL) technique, with fully bio-based chitosan (CS), agar, and phytic acid (PA) as key components. The coated wood demonstrated improved durability, flame resistance, and thermal stability. Particularly, the Wood-2 sample achieved a vertical burning test (UL-94) V-0 rate and a limiting oxygen index (LOI) of 53.1%, which exceeded most previous reported flame retardant coatings. Cone calorimeter test and infrared thermography analysis confirmed that a thick layer of intumescent char formed when the coating was exposed to heat, effectively hindering heat transfer and oxygen supply. This flame retardant effect is attributed to a synergistic mechanism involving nitrogen/phosphorus (N/P) elements. This study offers an environmentally friendly solution for wood flame retardancy and lays an experimental and theoretical foundation for the development of green aviation interior materials. Full article

The present paper discusses differences in the theoretical behavior of nonconventional biomasses during combustion according to their combustion parameters, focusing on their potential for sustainable energy valorization and their contribution to sustainable development. Data were obtained through thermogravimetric analysis (TGA) of biomasses from the local Galicia–North Portugal Euroregion. The samples tested were raw, nonwoody biomasses, specifically kiwi waste and gorse, and animal-derived biomasses, poultry and turkey manure. A wood pellet was also included as a reference conventional biofuel. Nonwoody biomass samples containing kaolin and calcium carbonate were also tested. Thermogravimetric analyses were performed on each biofuel under an oxidative atmosphere at different heating rates. With these data, different combustion parameters were calculated. The TGA results showed that the mean ignition temperature observed for animal-derived fuels was about 15 °C lower than for nonwoody biomasses at every heating rate, which indicates that they start to burn at lower temperatures. These animal-derived fuels generally presented better combustion parameters, suggesting that their combustion behavior is better; however, their high ash and moisture contents are problematic. These issues would be aggravated in real facilities, making them more difficult to use as fuel. The proportion of additives used had no effect on the parameters at lower heating rates, although they started to modify their tendency at 30 °C/min. For instance, the ignition index for non-additivated kiwi waste was 174.32 (wt. %/min³) × 10⁻³ compared to 143.78 (wt. %/min³) × 10⁻³ for kiwi with CaCO₃. Full article

The novelty lies in combining chemical and ecotoxicological approaches to evaluate the safety of ashes from different fuels. Its practical relevance is in demonstrating that only mixed firewood ash shows sufficiently low toxicity for safe use in home gardens, offering guidance for sustainable household ash management. The use of ash in agriculture as a fertilizer has become a topic which is gaining growing attention because of its high nutrient content and its capacity to enhance soil structure. Ash from the combustion of wood, coal or plant biomass, although at first glance it seems to be a useless residue, contains a large amount of components essential for the healthy development of plants. These include potassium, phosphorus, magnesium, calcium and many microelements that can significantly affect the yield and condition of crops. For this reason, it was deemed necessary to investigate the toxicity of ashes produced during the burning of solid materials. The study material consisted of samples collected under controlled conditions resulting from the burning of the following materials: lumps of hard coal larger than 60 mm, hard coal graded between 25 and 80 mm, fine hard coal ranging from 8 to 25 mm, wood pellets, and a mixture of firewood types. A leaching procedure was then carried out to obtain eluates from the individual ash types. The analyses made it possible to determine and evaluate the extent to which polycyclic aromatic hydrocarbons (PAHs) leach from ashes originating from different fuels. Furthermore, the effect of fuel type on the transfer of these substances into the water environment was established. Carcinogenic equivalents of ash solutions, as well as the acute ecotoxicity of the eluates, were also assessed using Microtox^® biotests with luminescent bacteria Aliivibrio fischeri. Based on the results, it was shown that the eluate derived from the combustion of mixed firewood exhibited the lowest toxicity, both with respect to PAH-related indicators and Microtox^® outcomes. In our view, only this type of ash can be regarded as suitable for agricultural application in home gardens. Full article

This study presents a comprehensive latitudinal analysis of air particulate matter (PM) across an 1400 km pollution corridor spanning Chile’s central-southern zone. We systematically analyzed PM_2.5 and PM₁₀ concentrations across eight major urban centers (2014–2015), providing crucial pre-Paris Agreement baseline data for South America’s most extensive air quality monitoring network. Our analysis reveals significant pollution gradients, with Coyhaique ranking one of the world’s most severely polluted cities (95th percentile globally, WHO database) and demonstrating an extreme 86% fine particulate matter ratio that far exceeds international urban standards. Residential wood combustion (RWC) demonstrates systematic correlations with fine PM concentrations (R² > 0.96), suggesting RWC is the dominant pollution driver across multiple climate zones. The documented pollution patterns represent a concerning continental-scale environmental pattern, with 4900–6500 annual premature deaths directly attributable to PM_2.5 exposure-one of the highest per-capita pollution mortality rates in South America. This work provides a methodological framework applicable to mountain-valley pollution systems globally while addressing critical knowledge gaps in regional air quality science. The evidence indicates the need for urgent implementation of comprehensive wood combustion control strategies and positions this research as essential baseline documentation for both national air quality policy and international climate change assessment frameworks. Full article