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Anaerobic digestion (AD) is one of the most preferred processes for the treatment of organic waste. However, additional processes such as co-digestion, pretreatment, and additive addition continue to be explored to remove the limits on the applicability of AD. This study investigated the effects of hydrophobic nanoporous silica aerogel (NpSA) synthesized from waste rice husks on the anaerobic co-digestion (AnCD) of the mixture consisting of sewage sludge and fruit processing industry wastes. All bioreactors containing NpSA-free, 0.1 g, 0.2 g, 0.5 g, and 1 g NpSA (0.03–0.3 gNpSA/gVSadded) were operated in a mesophilic-batch process. Biogas and methane yields increased from 346 mL/gVS (NpSA-free) to 387 mL/gVS and from 231 mL/gVS (NpSA-free) to 288 mL/gVS, respectively, with 0.1 g NpSA addition. NpSA additive increased biogas production in all bioreactors compared to the blank. However, biogas production rate and methane content increased faster at lower doses of NpSA. Maximum soluble chemical oxygen demand (sCOD), protein, carbohydrate, and volatile solid (VS) reductions were between 45–71%, 35–54%, 44–65%, and 34–91% for NpSA added mixtures, respectively. The hydrophobic NpSA additive was effective in improving the AnCD performance and biogas/methane production. Experimental results fit the kinetic models frequently preferred in such AD processes. In addition, the possible energy and financial potential of the produced methane were also discussed, and it was determined that the direct sale of methane gas produced by the addition of NpSA in the global market could provide 1.4 $/Lmixture more financial gain than the mixture NpSA-free. [ABSTRACT FROM AUTHOR]

By using carbon dioxide (CO 2) as carbon source, fossil sources can be replaced. In microbial electrosynthesis (MES), CO 2 and in situ produced hydrogen (H 2) are used for bacterial biofilm growth. Kyrpidia spormannii is a Knallgas bacterium with a protein content of 61% of its dry mass. It grows as a biofilm on the cathode in an oxic MES. The biomass can be used for the food and feed industry. A continuous process was established by applying a negative potential to harvest parts of the biofilm for use. The biofilm regenerated after being partly harvested. The system was operated at maximum coulombic efficiency, enabling the energy input to be minimized. A numerical model describing the growth of K. spormannii as a H 2 -oxidizing bacterium in an oxic MES system was developed. This helps predict growth behavior and efficiencies for further optimization. Autotrophic microbial electrosynthesis (MES) processes are mainly based on organisms that rely on carbon dioxide (CO 2) as an electron acceptor and typically have low biomass yields. However, there are few data on the process and efficiencies of oxic MES (OMES). In this study, we used the knallgas bacterium Kyrpidia spormannii to investigate biomass formation and energy efficiency of cathode-dependent growth. The study revealed that the process can be carried out with the same electron efficiency as conventional gas fermentation, but overcomes disadvantages, such as the use of explosive gas mixtures. When accounting only for the electron input via electrical energy, a solar energy demand of 67.89 kWh kg–1 dry biomass was determined. While anaerobic MES is ideally suited to produce methane, short-chain alcohols, and carboxylic acids, its aerobic counterpart could extend this important range of applications to not only protein for use in the food and feed sector, but also further complex products. [Display omitted] Oxic microbial electrosynthesis (OMES) using Kyrpidia spormannii can match the electron efficiency of gas fermentation, without producing explosive gas mixtures. It uses solar energy efficiently and has the potential to produce complex products, such as proteins, for food and feed instead of methane and alcohols, which are typical products of anoxic MES. Oxic microbial electrosynthesis (OMES) is a relatively new technology, particularly in the context of biofilm-based processes, which is now achieving a Technology Readiness Level (TRL) of 3 in laboratory reactors. Similar to other biofilm-based technologies, OMES faces both challenges and opportunities. One of the primary challenges will be identifying a reactor design that maximizes electrode surface area while simultaneously maintaining a predictable fluidic regime. Since OMES relies on an electrochemical system, reactor configuration must also minimize electrochemical losses. If biomass is intended to be the end product, it is important to consider that, over the duration of the experiment, microorganisms are likely to adapt to the changing process conditions, potentially enabling evolution-based optimization of biocatalysts. In the future, OMES is likely to compete with processes relying on anaerobic gas fermentation as a first step and subsequent usage of end products from this first step as feed for a second reaction step likely involving aerobic microorganisms. Full economic and ecological process assessment based on larger scale reactors will be necessary to decide under which circumstances which technology might be superior. [ABSTRACT FROM AUTHOR]

Policy is decisive to stimulate biogas expansion; but policy-related factors may also inhibit the development. This study explores policy risks in the Swedish biogas sector and identifies strategies to mitigate these risks. The study is based on three workshops and a survey with participation of biogas stakeholders. The findings reveal that two major policy risks significantly impact the Swedish biogas sector: the 'lack of long-term strategies' and the 'long and complicated permitting processes.' 'Limitations of permitted feedstocks' and 'limited system perspective—benefits of circular economy and sustainable food system' are also among the most probable risks. More clearly defined roles for authorities at different administrative levels and the promotion of life cycle perspectives are critical to mitigate these risks. The research emphasizes that both EU and national governments play vital roles in reducing policy risks through predictable and long-term biogas strategies. Without these interventions, the potential of the Swedish biogas sector may remain underutilized. [ABSTRACT FROM AUTHOR]

The global demand for renewable energy sources has been increasing. Microalgae is considered one of the best energy sources among renewable options, as it efficiently produces biofuel on a large scale. Pakistan has advantageous conditions for cultivating microalgae as a biofuel source, including abundant sunlight, favorable climate conditions, ample land and water resources. This research aims to identify suitable sites in Karachi for microalgae cultivation using geographic information systems. The potential sites were classified into four categories: highly suitable, moderately suitable, less suitable, and unfavorable. The study shows that Karachi provides an environment conducive to large-scale microalgae cultivation, which could help to alleviate energy shortages. Moreover, identifying viable cultivation locations can attract domestic and international interest, leading to future developments in the field. [ABSTRACT FROM AUTHOR]

Biomass is an eco-friendly alternative sustainable renewable energy source when agricultural wastes are effectively utilized. It has become critical to assess the suitability of biofuel briquettes as an energy source for cooking, electricity, and fuel for heating. Certainly, the integration of energy sources into energy policies is warranted, considering the huge potential to provide energy for rural communities and the peri-urban poor with alternative fuel. This research describes a technique to generate densified hybrid solid biofuels from biomass waste and valorize them. Prosopis africana pod (PAP) and cowpea husk (CPH) wastes were combined to create high-energy-density fuel briquettes. The experiment involves improving briquette manufacturing parameters using response surface methodology to better understand the impacts of particle sizes, composition, binder concentrations, and densification pressures on briquette performance. The optimal conditions were particle size 150 µm, 50% PAP, 10% binder concentration, and densification pressure 103.42 kN/m2. The optimum values for burning rate, ignition time, specific fuel consumption, and heating value were 0.35 g/min, 2.75 min, 0.186 g/L, and 22.98 MJ/kg, respectively. The findings show the potential for using PAP and CPH biomass waste to produce environmentally friendly energy sources. This increases the potential agro-waste feedstocks for bioenergy in developing countries, reducing energy insecurity while promoting waste management, renewable energy generation, and environmental sustainability. [ABSTRACT FROM AUTHOR]

Since the launch of the first biofuel policy (Proalcool), in 1975, Brazil has developed a remarkable ethanol fuel industry which is now a major component of the country's strategy to reduce greenhouse gas (GHG) emissions. In this paper we analyze how biofuel policies have affected the ethanol industry and how this industry has contributed to GHG emission reduction. Our study innovates by considering both Life Cycle Assessment (LCA) and Land Use Change (LUC) emissions and for covering the period from 1975 to 2022. We found that the use of ethanol fuel allowed significant emission savings for the transportation sector, causing GHG emission reductions of 39–46% compared with gasoline and a total avoided emission greater than 828 million metric tons of carbon dioxide equivalent. We identified that market drivers have been more decisive in fostering the ethanol industry, but biofuel policies also have a major influence on the development of the ethanol sector. Due to that, there are concerns about the environmental impact of the new biofuel policy (RenovaBio) as it ignores LUC emissions. To avoid adverse effects, we recommend that biofuel policies should consider all potential adverse impacts of LUC and should also involve strong actions aiming to halt deforestation. [ABSTRACT FROM AUTHOR]

In determining biogas potential, the current number of materials that can be used in biogas production is as important as the availability and usability of the materials. Potential studies that were conducted without knowing the structures of the systems in which these materials could be evaluated give us only the theoretical upper limit that can be reached. The 'theoretical', 'technical' and 'economic' potential distinctions made to prevent the error from occurring unfortunately only take into account the availability of the materials, and the process sizes and properties are either very limited or not at all. This causes the facilities established by considering existing potential research to fail in implementation or operate at low capacity. In this study, the importance of the international production chain of the apparel industry in Turkey's economy is examined. The study is based on Konya, which has a total of 1,079,644 cattle animals, 737,395 of which are dairy cattle. In the study, the number of dairy cattle with high waste collectability rates was particularly taken into consideration. Thus, the seasonal number of changes that may occur was tried to be avoided. In this study, the number of animals per farm and the distances between businesses were taken into consideration, and the biogas systems that could be installed were evaluated within this framework. Series of analysis were made under 3 different scenarios. In the first scenario, it was assumed that biogas systems would be installed by waste-generating enterprises. The installation of village-type common biogas systems was examined when possible within the scope of the second scenario. In the third scenario, the installation of district-based biogas systems was considered. Considering the difficulties in collecting the waste of enterprises with less than 50 cattle (due to the lack of regular collection systems), it is assumed that the waste of these enterprises cannot be used in village or central systems. According to the data obtained, Scenario 1 stands out in terms of creating employment and reducing environmental problems. The 3rd Scenario was the most profitable in macroeconomic terms. However, it was emphasized that the 1st and 2nd Scenarios stand out in terms of the sustainability of the systems. [ABSTRACT FROM AUTHOR]

Fish processing plants generate significant waste annually, which harms the environment. To tackle this, the waste can be converted into biofuel, pharmaceuticals, fertilizer, and animal feed. Biofuels, specifically biogas and biodiesel, are emphasized for their eco-friendly properties that help combat global warming. The study focuses on producing biodiesel through transesterification and biogas via anaerobic digestion of fish waste. Analyses of the rate constant (K), activation energy (Ea), entropy (ΔS), enthalpy (ΔH), and Gibbs free energy (ΔG) at varied temperatures show highest Ea, K, ΔH, and ΔS values of 60.74 kJ/mol, 31.43 s−1, 66.01 kJ/mol, and 30.99 kJ/mol K, respectively. The biodiesel was also characterized by Fourier transform infrared (FTIR) spectroscopy and kinematic viscosity. Additionally, the properties; relative density, viscosity, oxidation stability, pour point, cloud point, flash point, and cetane number were found to be 0.669, 5.090 mm2s−1, >7, −7 °C, 0.999 °C, 151 °C, and 51, respectively. Biogas production using varying ratios of fish waste and cow dung (1:1,1:2, 1:3, and 1:4) indicates that a 1:4 ratio yields optimal results with 69% methane (CH4) and 21.5% carbon dioxide (CO2), suitable for scalable biogas production. The process is efficient at a neutral pH (7.1–7.3) and 27 °C, offering a viable solution to reduce fish waste pollution while generating renewable energy. Finally, a proposed model of a biodigester for optimum biogas production is discussed. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to comprehensively analyze renewable energy alternatives in Brazil, focusing on identifying the most suitable option for investment in the country's sustainable development. Design/methodology/approach: The study adopts the step-wise weight assessment ratio analysis-multiobjective optimization by ratio analysis −3NAG (a combination of three normalization methods) methodology, a multicriteria decision-making approach, to evaluate and rank renewable energy sources based on key criteria such as resource availability, cost-effectiveness, job creation potential and environmental impact. Findings: The analysis reveals that solar energy emerges as the preferred choice for Brazil, offering significant advantages over other alternatives such as hydroelectric, wind and biomass energy. Solar energy's distributed generation capability, cost reduction trends and positive environmental impact contribute to its favorable position in meeting Brazil's energy needs. Research limitations/implications: While the study provides valuable insights into renewable energy selection, there are limitations regarding the criteria' scope and the exclusion of specific renewable energy options. Future research could explore sensitivity analyses and incorporate additional criteria to enhance the study's comprehensiveness. Originality/value: This research contributes to the existing literature by thoroughly analyzing renewable energy alternatives in Brazil using a robust multicriteria decision-making methodology. The study's findings provide actionable guidance for policymakers, businesses and stakeholders seeking to promote sustainable energy development in the country. [ABSTRACT FROM AUTHOR]

Hydrogen is a probable alternative fuel for both stationary and automotive engine applications due to its properties like high energy content and persistent availability. However, using hydrogen only as a fuel for engines was almost impossible; thus, hydrogen co-combusting with diesel and several biomass-based biofuels will be advisable. As viscosity plays a significant role in combustion, the application of biodiesel was classified as high viscous fuel and low viscous fuel for investigation with hydrogen in compression ignition engines. The present study aims to reconnoitre the prospects of using hydrogen-enriched diesel-biodiesel blends with advanced combustion technology. The present work also examines advanced combustion technologies, including reactivity-controlled compression ignition (RCCI), homogenous charge compression ignition (HCCI), and laser ignition technology. This review shed light on the properties of hydrogen-enriched biodiesel blends, engine operating parameters, and their impact on engine characteristics. This comprehensive review offered a distinct view to the academics for improving the performance, combustion, and emission characteristics of CI engines fuelled with hydrogen-enriched biodiesel-diesel. Further, the review progressed with the aforesaid operating conditions and advanced combustion technology. • Hydrogen-enriched diesel/biodiesel with advanced combustion technology are reviewed. • Various production methods of hydrogen are comprehensively presented. • Low-temperature combustion concepts with adding hydrogen are discussed in detail. • RCCI/HCCI engines, and laser ignition technology using hydrogen are scrutinized. • Adding hydrogen with high/low-viscous fuel alters the engine output characteristics. [ABSTRACT FROM AUTHOR]

Electrofermentation improves the performance of microbes cultured on organic byproducts such as glycerol or acetate by supplementing cofactors or resolving cofactor imbalances. By employing Escherichia coli as the candidate microbe in electrofermentation, its broad product range, ease of genetic manipulation and predictable performance in both aerobic and anoxic conditions can be leveraged. Here, we demonstrate anodic electrofermentation for simultaneous production of electricity and the biofuel butanol, using engineered electroactive E. coli grown on organic byproducts. Relative to glucose as carbon source, acetate produced mainly electrical current achieving ∼80% of the electron output of glucose plus some butanol. Glycerol was the most effective carbon source tested for the engineered system resulting in the highest delivery of electrons and the highest butanol production. Increasing glycerol concentration and electrode surface area commensurately increased electron output without decreasing butanol production. Accordingly, E. coli can be applied more widely in electrofermentation to deliver a wide range of chemicals and electrons using waste byproducts as carbon feedstocks. [ABSTRACT FROM AUTHOR]

The present study investigates the thermodynamics analysis of a trigeneration system using a gasifier system. An Organic Rankine Cycle (ORC) system is used to heat recovery and consequently, supplying the cooling demand. The first and second laws of thermodynamics are used to energy and exergy analysis of the system. Some thermodynamic parameters which affect the system performance including combustion temperature, gasifier temperature, compressor isentropic efficiency, gas turbine isentropic efficiency, compressor pressure ratio, and ORC pressure are parametrically analysed and their contribution in improving the efficiency and economy of the system is investigated. To the sustainable performance of the combined system, we need an evolutionary algorithm to identify the optimum values of thermodynamic parameters that have an impact on system performance. Hence, the Multi-Objective Particle Swarm Optimization (MOPSO) algorithm is used to find the best values of decision variables. The most striking result to emerge from the optimisation.optimisation is that implementing the MOPSO algorithm improves the exergy efficiency by 5.17% and reduces the total cost of the system by 1.9%. [ABSTRACT FROM AUTHOR]

South Africa's national development plan has outlined aspirations to achieve a sustainable environment. However, the country remains bound for an unsustainable trajectory. Despite this ecological issue, no studies have probed how biomass and coal energy impact ecological quality. In light of this gap, this study inspects the environmental effect of political risk, coal energy, and biomass energy in South Africa. Also, this study integrates economic growth and natural resources into its framework. This study uses the load capacity factor (LC), which is a more aggregate proxy of ecological quality due to its accounting for the demand and supply aspect of the environment. This study uses the dynamic autoregressive distributive lag estimator (ARDL), which is capable of not only providing details of the influence of each determinant on LC in the long and short term but also of capturing the counterfactual shock of positive or negative exogenous variables on the LC. The kernel regularized least squares (KRLS) method is used for a robustness analysis of the dynamic ARDL approach. Furthermore, the findings of the dynamic ARDL simulation estimator disclose the negative impact of economic growth on the LC, thereby contributing to environmental deterioration by 0.552%. Natural resources and coal energy have an adverse impact on the LC, indicating a reduction in environmental sustainability by 0.037% and 0.290%, respectively. Meanwhile, biomass contributes to the LC, thereby promoting ecological quality by 0.421%. Political risk contributes to the reduction in the LC. This research provides pertinent policy considerations for policymakers and governments in South Africa, suggesting that the government of South Africa should invest in biomass energy and sustainable extraction procedures since biomass energy has a vital role in increasing ecological quality. [ABSTRACT FROM AUTHOR]

The study assessed the yield and quality as well as the energy potential of biomass from stalks and pomace of four grape varieties, Riesling, Chardonnay, Zweigelt, and Merlot Vitis vinifera L., grown in temperate climate conditions. The research is innovative because the evaluation of the energy potential of biomass originating from Vitis vinifera L. has not been carried out so far in the northern wine-growing regions. Field studies were conducted in 2023 in the Experimental Vineyard of the University of Life Sciences in Lublin, located in southeastern Poland. Biometric yield assessment showed that Chardonnay vines were characterized by the lowest mass of clusters and peduncles, number of berries in the cluster, berry diameter, and peduncle size, and at the same time the highest berry mass among the assessed biotypes. Merlot clusters were characterized by the highest mass of clusters and the largest peduncles. Riesling had the most berries in the cluster, the heaviest peduncles, and the highest share of peduncles in the cluster mass (8.99%). For grape pomace, the LHV values range from 15.98 MJ kg−1 for the Chardonnay variety to 16.91 MJ kg−1 for Riesling, while for peduncles, these values range from 15.11 MJ·kg−1 for Merlot and Riesling to 15.26 MJ kg−1 for Chardonnay. The differences in pollutant emissions are more pronounced between grapevine varieties than between types of biomass (pomace vs. peduncles). The greatest variation among varieties was observed for carbon dioxide (CO2) emissions in the pomace category, while the smallest differences were noted for sulfur dioxide (SO2) emissions. Total gas emissions were highest for Zweigelt pomace (7.72 Nm3 kg−1) and lowest for Merlot (6.99 Nm3 kg−1), while for stalks, Chardonnay had the highest values (6.77 Nm3 kg−1) and Merlot the lowest (7.32 Nm3 kg−1). The largest variation among varieties was observed in the pomace category. These results indicate differences in exhaust gas emissions for different plant parts and grape varieties, which are relevant for optimizing production processes and ensuring sustainable development. [ABSTRACT FROM AUTHOR]

This study examines the maritime trade of biofuels in Spain, focusing on its contribution to the global energy transition and sustainable development. Using data from Spain's 28 port authorities, the research identifies key trends, trade dynamics, and port-specific roles. This study reveals that Spain is a net biofuel exporter, maintaining a positive balance of 5.20 million tons throughout the study period. Export volumes peaked in 2021 at 1.63 million tons, while imports have shown steady growth over the past seven years. Barcelona and Bilbao emerge as strategic ports with robust connections to the Netherlands, Italy, and Belgium, reinforcing Spain's role in the international biofuel market. This study incorporates hierarchical decision models, including classification trees, to analyze sustainability and efficiency factors in biofuel trade. These models unveil key interactions between variables such as cargo type, origin country, and port characteristics, offering actionable strategies to optimize port operations and enhance Spain's standing in the global biofuels sector. This research highlights the importance of sustainable port infrastructure and international collaboration to strengthen Spain's position as a pivotal player in the global energy transition. [ABSTRACT FROM AUTHOR]

The recent advancements in using micro-organisms effectively for biofuels are the key reason for conducting this study. Therefore, the current theoretical work addresses the Oswald – DeWaele power-law models of bioconvection nanofluid flow containing both nanoparticles and gyrotactic microorganisms. This study has examined two major elements of gyrotactic microorganisms: swimming behavior and the development of bioconvection structures. In addition, the Lie-group approach of transformations is used to establish similarity representations of the governing equations rather than the existing transformations. To achieve the model's aims, the Legendre-based collocation method (LBCM) was adopted. The findings are analyzed using graphs to examine the patterns of the relevant parameters in the problem. Compared with existing results, the present analysis is effective, fast-converging, and accurate. The bioconvection parameters have a significant impact on the density of motile microorganisms, nanoparticle volume fraction, flow momentum, and temperature distribution. Furthermore, the current work finds application in nanofluid fuel. [ABSTRACT FROM AUTHOR]

In this study, the available energy potential (AEP) from agricultural and animal waste in Turkey in 2021, which is an important agricultural country, was calculated using Turkish Statistical Institute data and presented with digital maps prepared using the ArcGIS program. It was determined that Turkey has a total of 4.6 × 108 GJ of AEP, 3.7 × 104 GJ from agricultural wastes and 8.7 × 107 GJ from animal wastes. Furthermore, 81.06% of the AEP is composed of agricultural wastes, and 18.94% is animal wastes. Şanlıurfa has the highest AEP from agricultural wastes (4 × 107 GJ), while Konya has the highest AEP from animal wastes (4.3 × 106 GJ). The provinces with the highest AEP from the total of agricultural and animal wastes are Şanlıurfa (4.2 × 107 GJ) and Konya (3.4 × 107 GJ). With the energy produced from biomass orginating from agricultural and animal waste, nearly 40% of Turkey's energy needs will be met. The use of agricultural and animal biomass for energy supply will have various benefits for Turkey. The main benefits are: reduction of greenhouse gas emissions and environmental pollution, reduction of energy imports into the country, and disposal of agricultural and animal waste. [ABSTRACT FROM AUTHOR]

The emerging biofuel industry plays a pivotal role in transitioning from conventional sources of energy to renewable sources. The advent of biodiesel can revolutionize the petroleum sector without requiring major modifications to existing diesel engines. Catalysts have played a significant role in transesterification and esterification reactions to produce biodiesel. Recent years have seen an acceleration in the use of ionic liquid catalysts for fatty acid methyl ester (FAME) production owing to their catalytic efficiency and enhanced stability. They act as greener solvents and catalysers which can be designed with high specificity. This study outlines the advancements in ionic liquid catalysts, primarily basic ionic liquid catalysts which have a faster reaction rate and higher efficiency than their Brønsted acidic counterparts. The high cost and sensitivity to fatty acids are major issues for their implementation in the industry. However, the ability to reuse them and their catalytic prowess are promising prospects that can be explored further. [ABSTRACT FROM AUTHOR]

In this study, various solvents were evaluated for their efficacy in extracting biofuel components, such as acetone (ACT), n-butanol (nBuOH), ethanol (EtOH), and isobutanol (IBA) from aqueous solution at 37.5 °C and atmospheric pressure using liquid-liquid extraction (LLE). The extraction performance of solvents was evaluated by their solute distribution coefficients and selectivity. The experimental results are compared with theoretical prediction using ASPEN plus and the model shows an excellent fit. Among the solvents examined, 2,6-dimethyl-4-heptanol (DMHT) and 2-ethyl-1-hexanol (2E1H) are more effective solvents for the extraction of IBA and nBuOH from aqueous solution. [ABSTRACT FROM AUTHOR]

Conventional hydrogen production processes, which often involve fossil raw materials, emit significant amounts of carbon dioxide into the atmosphere. This study critically evaluates the feasibility of using sugarcane biomass as an energy source to produce green hydrogen. In the 2023/2024 harvest, Brazil, the world's largest sugarcane producer, processed approximately 713.2 million metric tons of sugarcane. This yielded 45.68 million metric tons of sugar and 29.69 billion liters of first-generation ethanol, equivalent to approximately 0.0416 liters of ethanol per kilogram of sugarcane. A systematic literature review was conducted using Scopus and Clarivate Analytics Web of Science, resulting in the assessment of 335 articles. The study has identified seven potential biohydrogen production methods, including two direct approaches from second-generation ethanol and five from integrated bioenergy systems. Experimental data indicate that second-generation ethanol can yield 594 MJ per metric ton of biomass, with additional energy recovery from lignin combustion (1705 MJ per metric ton). Moreover, advances in electrocatalytic reforming and plasma-driven hydrogen production have demonstrated high conversion efficiencies, addressing key technical barriers. The results highlight Brazil's strategic potential to integrate biohydrogen production within its existing bioenergy infrastructure. By leveraging sugarcane biomass for green hydrogen, the country can contribute significantly to the global transition to sustainable energy while enhancing its energy security. [ABSTRACT FROM AUTHOR]

Over recent decades, human activities have essentially depended on fossil fuels. The last Intergovernmental Panel on Climate Change reports recommend a shift to renewables and a more energy-efficient economy. To fulfill the potential of bioenergy, tools are required to overcome the complexities of the decision-making processes for viable projects. This work presents a decision-making tool to select the most feasible biomass residues and a case study of the state of Minas Gerais, in Brazil. Among the 13 evaluated criteria, eucalyptus residues demonstrated the highest potential for electricity production, followed by sugarcane bagasse and coffee husks. The choice of Minas Gerais as a case study is important due to its diverse agricultural landscape and the potential for biomass residue generation. The presented methodology uses the Analytical Hierarchy Process (AHP), a multi-criteria decision-making method (MCDM). Thirteen criteria were required to enable the best choice of biomass residue alternatives for electricity generation, which experts in the bioenergy field evaluated. The technical criterion was shown to be the one with the highest degree of importance. The results of the study identified that CO2eq emissions (11.46%) and electricity demand (ED) were the most relevant sub-criteria for prioritizing the viability of agricultural waste. Eucalyptus was ranked as the most promising biomass, followed by sugarcane bagasse and coffee husks. In addition, the use of GIS tools made it possible to map the regions with the greatest potential in Minas Gerais, providing a robust approach to identifying strategic sites for bioenergy. [ABSTRACT FROM AUTHOR]

Enhancement of a sustainable environment through the choice of a selective catalyst with high activity, regeneration nature, and high stability is an important aspect to be focused on to achieve a high yield and maximum conversion of feedstock to biodiesel (1st generation biofuel), and also in the biomass valorization/pyrolysis (2nd generation biofuel synthesis). Depending on the nature of the catalyst and synthesis method adopted for biofuel production and biomass valorization, the variations in the process conditions, final yield, and conversion are varied accordingly. A prospective development and application of perovskite catalysts in the synthesis of 1st and 2nd generation biofuels using various process intensification strategies for the development of a clean and green environment is reviewed in this study. The synthesis of types of perovskite catalysts polycrystalline, nano‐sized, and powdered oxide are also discussed in this review. It is also concluded that, apart from other process parameters, molar ratio is one of the most influencing sensitive factors in the case of 1st generation biofuel synthesis, whereas during the production of 2nd generation biofuels, catalyst concentration and liquid–solid ratio are more significant process parameters that change based on the nature of the catalyst selected for the reaction. [ABSTRACT FROM AUTHOR]

In an effort to explore the potential energy of biomass and reduce industrial reliance on fossil fuels, this study investigates the liquefaction of poplar wood using supercritical methanol and a CuMgAlOx catalyst. It assesses the composition of liquefied products and performs a comprehensive life‐cycle assessment. Results display that at 360°C, with 1 h of CuMgAlOx, poplar wood's conversion rate reached 98.4%. The proportion of alcoholic compounds in the liquefaction products increased dramatically from 7.99% without a catalyst to 70.81% with it, a rise of 786.23%. Moreover, the process's global warming potential (GWP) intensity is significantly lower at 0.886 gCO2eq/MJ compared to the 93 gCO2eq/MJ from conventional petroleum refining, underscoring its substantial emission reduction potential. [ABSTRACT FROM AUTHOR]

The transport structure of any company includes marine transport, whose engines use marine fuel and fleet fuel oil. Both types of fuel contain heavy oil fractions, the use of which causes environmental problems: high emissions of pollutants during engine operation, carbon dioxide emissions, accidents and pollution of water with oil products, etc. At the same time, each of these fuels contains a diesel fraction. This article proposes to replace the petroleum diesel fraction with biodiesel fuel obtained from renewable resources, since its characteristics are as close as possible to the quality indicators of the petroleum diesel fraction. This reduces harmful emissions when large amounts of fuel are burned in marine engines. In the event of an accident or a spill, unlike petroleum products, biodiesel fuel decomposes on its own within a few months. The cost of environmentally friendly marine fuel will be lower than the cost of low-viscosity marine fuel made from petroleum components. [ABSTRACT FROM AUTHOR]

This study consists of the synthesis of sustainable heterogeneous catalysts comprising dilacunary phosphotungstate and different acidic supports (zeolite HY and hydrous zirconia) via the incipient wet impregnation method. The catalysts were characterized by various physicochemical techniques and evaluated for solvent-free cleaner synthesis of n-butyl levulinate, a promising biofuel additive, under mild conditions. By undertaking a detailed optimization study, an outstanding selectivity of n-butyl levulinate (≥93%), as well as exceptional turnover numbers (>1300), was achieved. The reaction kinetics and order were investigated for both catalytic systems, revealing adherence to a true chemical step. The effect of the support was studied to compare the activity of the catalysts. The selected best catalyst was regenerated and recycled for multiple runs. Its versatility was explored in the esterification of a range of bio-based molecules into various biofuel additives with remarkable selectivity. Interestingly, it achieved over 90% selectivity for a range of C1–C7 straight-chain alcohols, marking a significant accomplishment. A high-gravity approach and scale-up reactions were also explored to ensure the practical relevance of the findings, emphasizing the potential of the catalyst for broader application. [ABSTRACT FROM AUTHOR]

Gasification is a proven and eco-friendly route to generate chemical energy from biomass. Equilibrium models are widely used by researchers to simulate biomass gasification. Nevertheless, questions persist about the reliability, accuracy, and predictive capabilities of equilibrium models incorporating tar formation. To address this concern, two equilibrium models were developed using ASPEN Plus: one model included tar (EQM1) and the other excluded it (EQM2). To evaluate the accuracy of these models, their results were compared with experimental findings obtained under the same conditions. The simplified equilibrium model (EQM2), which is based on Gibbs energy minimization, significantly deviates from the experimental results due to the neglect of tar formation. After validating the model, a thorough parametric study was conducted to explore how gasifier temperature (GT), equivalence ratio (ER), and oxygen percentage in the air (OP) affect the composition of gases released from the gasifier and performance indicators. The gasifier temperature plays a critical role in enhancing H 2 production. However, it also leads to a reduction in the lower heating value of the syngas (LHV g) and consequently affects the cold gas efficiency (CGE). Increasing ER could enhance char conversion and gas production while reducing CO, H 2 , and CH 4 contents, resulting in a lower LHV g and CG-E. This study conclusively identifies a 40% OP as an optimal value. For OP>40%, the variations in char conversion and gas production become almost negligible. • Two equilibrium models (EQM1 and EQM2) were developed for biomass gasification. • In EQM1, tar was considered as a single component, and in EQM2, tar was omitted. • EMQ1 was more accurate in predicting the gas composition than EQM2. • The H 2 content was found to be increased by increasing OP and gasifier temperature. • OP = 40% was considered as an optimal value. [ABSTRACT FROM AUTHOR]

The application of genetic engineering in biofuel production has advanced significantly, driven by developments in genetic tools and omics technologies. These advancements have enhanced our understanding of lipid and carbohydrate metabolism, opening new avenues for metabolic engineering to optimize biofuel production. This review explores genetic strategies to improve the lipid content and fatty acid profiles for biodiesel production, as well as innovations in engineering for one-step biobutanol synthesis using cyanobacteria. Strategies for carbohydrate accumulation are also examined, highlighting their role in biofuel production. Additionally, the review evaluates the environmental risks associated with large-scale fourth-generation biofuel production. The findings emphasize the potential of genetic engineering to transform microalgae into highly efficient biofuel platforms capable of producing biodiesel, biobutanol, and other liquid biofuels. By addressing critical challenges and leveraging cutting-edge technologies, this research contributes to the development of sustainable and economically viable biofuel production systems. [Display omitted] • Genetic tools optimize microalgae for biodiesel and biobutanol production. • CRISPR/Cas9 enhances lipid biosynthesis in microalgae for biofuel applications. • Blocking starch pathways redirects carbon to lipids, boosting biodiesel yields. • Engineering Kennedy pathway enzymes increases TAG content in microalgae. • Modified microalgae enhance biobutanol production via one-step synthesis. [ABSTRACT FROM AUTHOR]

Carbon Capture and Storage (CCS), along with Bioenergy with Carbon Capture and Storage (BECCS), feature heavily in climate mitigation scenarios. Nevertheless, the technologies remain controversial within the broader mitigation discourse, in part for their potential to excuse delay in more ambitious emissions reductions in the short term. Sweden has included BECCS and CCS as proposed "supplementary measures" to enable the country to meet its ambitious target of achieving net negative emissions by 2045. Hajer's Argumentative Approach to Discourse Analysis is applied to Swedish parliamentary speeches, motions, and written questions and answers, to uncover the storylines and attendant assumptions constituting Swedish policy deliberation regarding CCS and BECCS. This study finds that by problematizing climate change as an issue of emissions, actors position CCS and BECCS within a dominant neoliberal discourse and characterize them as tools to facilitate a green transition centering on industrial and economic competitiveness. This discourse lacks detail, and risks delay by oversimplifying the needs and requirements for CCS and BECCS deployment. Meanwhile, a CCS-critical discourse acknowledges the need for negative emissions but challenges storylines portraying the technology as inexpensive or easy to deploy rapidly. If pursued, this discourse could serve to sharpen the debate about the technologies and bring planning in line with aspirations, helping to avert risks of delay. [ABSTRACT FROM AUTHOR]

The cellulose flakes derived from waste pomelo peel are judiciously designed as the dual-functional matrix for electrodes and hydrogel electrolytes into a flexible rocking-chair zinc-ion battery. [Display omitted] • The pomelo peel cellulose is designed as the dual-functional matrix for flexible rocking-chair zinc-ion batteries. • The new-style sandwich-type structure endows the flexible electrode with fast ion and electron transportation. • The pomelo peel cellulose-based hydrogel electrolyte is equipped with a superior ionic conductivity. • The assembled flexible rocking-chair zinc-ion battery presents high electrochemical and mechanical stability. Aqueous zinc-ion batteries are attracting extensive attention due to the long-term service life and credible safety as well as the superior price performance between the low cost of manufacture and high energy density. The fabrication of inexpensive, high-performance flexible solid-state zinc-ion batteries, thus, are urgently need for the blooming wearable electronics. Herein, as a proof-of-concept study of waste into wealth, cellulose flakes derived from waste pomelo peel are utilized as the substrate for electrodes and hydrogel electrolytes into a flexible rocking-chair zinc-ion battery. The unique sandwich-type structure holding the flake-like cellulose substrate and linear carbon nanotubes endows the flexible cathode and anode with fast ion and electron transportation. The obtained cellulose-based hydrogel electrolytes on account of special affinity with aqueous ZnSO 4 electrolyte output an excellent ionic conductivity. The assembled flexible rocking-chair zinc-ion battery benefitting from the synergistic effect of sandwich-type electrodes and cellulose-based hydrogel electrolytes demonstrates outstanding electrochemical performance and mechanical properties. This work not only puts up an effective roadmap for flexible battery devices, but also reveals the great potential of waste biomass materials in energy storage applications. [ABSTRACT FROM AUTHOR]

This study proposes a multi-energy complementary heating system that uses solar energy combined with biomass energy as the main heat source, with electricity as an auxiliary heat source. The system aims to tackle the low efficiency, high energy consumption, and pollution associated with traditional heating methods in rural southern Xinjiang, enhancing performance and productivity. It is designed to operate in five modes based on the region's climate and building heat load requirements. An experimental platform was set up in eight rural households in Tumushuk City, Xinjiang, where winter heating tests were conducted. The goal of this study was to analyze the economic and environmental benefits of the system. The results showed that the energy utilization efficiencies of the five modes were 56.84%, 74.34%, 70.1%, 63.13%, and 59.68%. The corresponding CO2 emissions were 3.56 kg/d, 45.09 kg/d, 105.75 kg/d, 30.97 kg/d, and 76.79 kg/d. The environmental and economic costs for each mode were 0.0493 USD/d, 0.6398 USD/d, 1.5029 USD/d, 0.4384 USD/d, and 1.0905 USD/d. It is clear that as an auxiliary heat source, biomass energy is more beneficial than electricity. All five modes maintained indoor temperatures of 18 °C or higher, meeting winter heating needs in cold regions. The results of this study provide important data support for the promotion and application of solar and biomass heating systems in the rural areas of southern Xinjiang and also provide valuable references for solving the problem of decentralized heating in rural areas. [ABSTRACT FROM AUTHOR]

This study investigated the capability of Clostridium beijerinckii TISTR 1461 to utilize mixed sugars (glucose and xylose) in synthetic media and sweet sorghum bagasse (SSB) hydrolysate for butanol production. Synthetic media containing 60 g/L of glucose and xylose at various ratios were used for butanol production. C. beijerinckii TISTR 1461 preferentially utilized glucose over xylose for butanol production. The highest butanol concentration (PB, 10.25–10.60 g/L), butanol yield (YB/S, 0.27–0.28 g/g), butanol productivity (QB, 0.22 g/L·h), and sugar consumption (SC, 61–63%) were achieved when the glucose content was at least 75% of the total sugars. When an SSB hydrolysate (produced via enzymatic hydrolysis) containing 60.83 g/L of total sugars (glucose:xylose ratio = 88:12, w/w) was used as a substrate for butanol production, the SSB hydrolysate supplemented with 1 g/L of yeast extract and buffers significantly yielded higher PB (15.10 g/L), YB/S (0.31 g/g), QB (0.31 g/L·h), and SC (82%) values compared to the synthetic media. These results indicate that sweet sorghum bagasse hydrolysates containing glucose and xylose mixtures show promise as cost-effective substrates for sustainable butanol fermentation, demonstrating the potential of agricultural residues in biofuel production. [ABSTRACT FROM AUTHOR]