Band 10, Heft 7-9

This paper explores the energy absorption capacity of biocomposites and its impact on sustainability and environmental benefits. Biocomposites consisting of natural fibers within a polymer matrix have attracted attention for their potential to improve impact resistance and safety while reducing environmental impact. This review critically examines the current state of research in this field, highlighting the importance of biocomposites in utilizing renewable and recyclable resources, energy-efficient processing, minimizing toxicological impacts, and promoting responsible waste management. This also highlights the importance of assessing emissions, including volatile organic compounds and nanoparticles, from an environmental and toxicological perspective. Additionally, the paper takes into account the degradation susceptibility of sustainable biocomposites, emphasizing the need to ensure their structural integrity during their service life and their ultimate biodegradability and assimilability during composting. The results presented in this review highlight the multifaceted advantages of biocomposites, making them a promising choice for sustainable materials with excellent energy absorption capabilities.

This study explores the development and optimization of polymer composite-based wind turbine blades, integrating glass fiber reinforced plastic (GFRP) with shape memory alloy (SMA) to enhance performance in wind energy harvesting. Advances in materials science, aerodynamics, computational modelling, and structural analysis have been leveraged to improve blade efficiency, durability, and self-adaptive capabilities. The research employs finite element analysis (FEA) and artificial neural networks (ANN) to evaluate the mechanical behaviour of composite blades under varying loads. A graded beam model was developed to assess the effects of ply drop-off and material distribution on structural integrity. Experimental validation confirmed that SMA integration enhances blade deformation recovery, mitigating stress accumulation and improving aerodynamic stability. The results demonstrate that GFRP-SMA blades achieve a performance coefficient approaching the Betz limit (0.5923), reducing deflections and improving load response. Despite these advancements, challenges remain in optimizing SMA wire placement, adhesion, and actuation efficiency. Future work should focus on refining material interfaces, developing adaptive control mechanisms, and validating the model in full-scale wind turbine applications. This study contributes to the next-generation smart wind turbine blade design, addressing structural limitations while enhancing energy efficiency and operational resilience.

The electrical conductivity of Carbon Fiber Reinforced Epoxy Composite (CFRE) is poor and need more improvement to be used in more applications such as deicing processes. Functionalized Graphene Nanoplatelets (FGNP) are used in present study to improve and enhance the electrical conductivity of CFRE by coating on its top surface. The results show that the electrical conductivity of CFRE is increased significantly by 11 times with percentage of improvement of 1,110 %. The effect of Joule heating in CFRE/FGNP specimen is also studied. The results show that the self-heating of CFRE is improved after coating it with FGNP. The self-heating of CFRE/FGNP specimen becomes more efficient and homogeneous, reaching high levels of temperature, more than CFRE neat at the same applied voltage. Tensile test is also performed by applying axial tensile load on the CFRE/FGNP specimen to investigate the effect of tensile load on its electrical conductivity. Therefore, it is found that the electrical resistivity of CFRE/FGNP is increased by increasing the applied tensile load.

This study explores advancements in energy harvesting using smart materials and composite structures, focusing on integrating shape memory alloys (SMAs) into wind turbine blades. The research investigates the structural and thermo-mechanical behavior of glass fiber-reinforced polymer (GFRP) composites and SMA wires, emphasizing their potential in improving blade adaptability and stress recovery. Finite Element Analysis (FEA) and experimental methods are utilized to evaluate deflection, load correlation, and actuation efficiency. Results demonstrate that suspended SMA wires enhance deflection recovery with lower energy loss compared to embedded configurations. A neural network model predicts deformation behavior based on load, current, and wire count. Additionally, SMA integration improves the power coefficient (Cp), bringing turbine efficiency closer to the Betz limit. Despite challenges such as nonuniform prestrain and material degradation at attachment points, this study confirms the feasibility of SMA-driven adaptive blades for wind energy applications. Future work includes optimizing SMA deployment in real-scale wind turbines through dynamic analysis and aerodynamic performance testing.

Vegetable oils are being considered as bio-based transformer liquid alternatives due to their biodegradability and potential for environmental impact reduction. Considering the depletion of mineral oils due to their petroleum-based origins, it appears that bio-based liquids could be viable alternatives for transformer applications. These liquids also show promise for a variety of other electrical and heat transfer applications, such as capacitors, cables, circuit breakers, and tap changers. They are derived from a variety of plants, have cost benefits over synthetic oils and are plentiful in many places. Although bio-based liquids have many benefits, they also have limitations. This includes poor thermo-dielectric performance. Adding nanoparticles to bio-based liquids at the right concentration can address these issues. Although there has been significant progress in research and development regarding the use of nanoparticles in bio-based liquids, no single type of nanoparticle has consistently proven to outperform others in all aspects. This review explores techniques for increasing the efficacy of bio-based liquids by incorporating nanoparticles to form bio-based liquid nanocomposites. It covers contemporary experimental studies on bio-based liquid nanocomposites, including preparation, stability tests, thermal characteristics, and dielectric characteristics. Furthermore, clarifies the fundamental principles that underpin the observed findings in this promising topic. This review seeks to contribute to the growing body of research on bio-based liquid nanocomposites in the field of transformers.

Biomass burning remains widespread in Sub-Saharan Africa (SSA), driven by a complex interplay of factors: technological limitations, colonial-era policies that contributed to deforestation, cultural practices, unmanaged waste disposal resulting in dumpsite fires, vegetation burning for land preparation, politically motivated fires from riots and protests, climate change-induced wildfires, and traditional cooking and heating practices rooted in poverty and insufficient land management strategies. This narrative review assesses biomass burning and biochar developments in SSA, highlighting the environmental impacts and viable mitigation strategies. Satellite data analysis reveals that Côte d’Ivoire experienced 122,014 agricultural fires from 2016 to 2019, peaking at 13,387 in February 2016. In 2019, Nigeria recorded 86,464 fires, resulting in approximately 0.019 Tg of black carbon emissions. Ghana reported 0.014 Tg of black carbon emissions, with burn scars comparable to Nigeria. Open vegetation burning in Zambia and Southern Africa during 2000 resulted in a burned area of 210,000–830,000 km 2 , emitting 18–31 Tg of carbon monoxide. SSA has a technically recoverable biomass of no less than 21,646 PJ, with approximately 1,986.5 PJ available from woody biomass, yet only 25 % of this resource is utilized, indicating significant underutilization. Biochar, derived from biomass, offers significant benefits for enhancing soil fertility, bioenergy production, carbon sequestration, and pollution control. Converting crop residues to biochar can mitigate up to 0.89 tons of CO 2 per ton of residues. In Cameroon, transforming 2,000 kg of agricultural waste into biochar could prevent 939.7 kg CO 2 eq emissions. However, SSA accounts for only 4.8 % of global biochar production, constrained by socio-economic, technological, and policy barriers. To improve biochar adoption and mitigate biomass burning impacts, this review recommends regional strategies including knowledge sharing, capacity building, policy incentives, public participation, sustainable management practices, and investment in bioenergy initiatives.