Energy nexus最新文献

Biodiesel is generally obtained by transesterification and esterification of appropriate feedstocks facilitated by a catalyst. It has emerged to be one of the most potential alternatives for the conventional fuels gaining worldwide attention. Heterogeneous catalysts are usually preferred than homogeneous for biodiesel synthesis due to facile separation and insignificant soap formation. However, the separation still possesses difficulty leading to mass transfer hindrance. Therefore, these catalysts can be further modified using magnetic separation techniques to develop magnetically separable catalysts. The magnetic nanoparticles (MNPs) are notable appealing catalysts due to huge surface area, high activity, amicable functional groups and structures, adaptable properties, conformity in pore size, and facile separation have made them desirable catalyst carriers for biodiesel synthesis. The MNPs are modified via functionalization to construct magnetically recoverable heterogeneous nanocatalysts. Magnetic catalysts can be utilized as a befitting option for biodiesel synthesis as these are environmentally benign, highly reusable and economically viable. The current review article discusses different magnetic solid catalysts such as magnetic base, acid, biocatalysts and bifunctional of acid base catalysts for efficient biodiesel synthesis. The prime focus of this paper rest on the catalytic performances of various magnetically recoverable catalysts, mechanisms and recyclability for biodiesel production processes. The synthesis methods of magnetic heterogeneous base and acid nanocatalysts, magnetic properties, functionalization and their reciprocity on the catalytic activity are reviewed in this article.

In the face of urgent global environmental challenges, the pursuit of sustainable technologies has become of utmost importance. Thermoacoustic technology has emerged as a promising energy conversion method with potential applications in various domains such as power generation, waste heat recovery, refrigeration, and air conditioning. This technology harnesses the thermodynamic properties of sound waves to convert heat into work or create cooling effects, offering simplicity, reliability, and environmental friendliness. Thermoacoustic devices, including refrigerators and engines, offer a low-carbon alternative to conventional power and refrigeration systems. With minimal mechanical components and no moving parts, they boast durability, easy maintenance, and reduced susceptibility to breakdowns. Despite the advantages, thermoacoustic technology currently faces challenges such as lower efficiency compared to traditional technologies. To achieve efficient performance, these devices depend on a comprehensive understanding of complex flow physics, which encompasses the transient nature of phenomena and the conversion of thermal and acoustic energies. This work provides a comprehensive overview of recent advancements in thermoacoustic technology, specifically emphasizing prime movers and refrigerators. We present insights into the working mechanisms and performance-affecting parameters of these devices, while discussing future research prospects and obstacles to commercial implementation. This review highlights the need for a deeper understanding of thermoacoustic system mechanisms, with a focus on addressing efficiency and scalability challenges. To make thermoacoustic systems more practical, research endeavors should concentrate on unraveling nonlinear phenomena, developing nonlinear thermoacoustics, and advancing transduction systems, system design, and component optimization. Innovative design strategies, beyond traditional multi-stage and phase-change approaches, along with exploration of alternative energy sources, hold the key to significantly improving overall thermoacoustic system performance, ensuring the continual evolution and prosperity of the field in the decades ahead.

Conventional agriculture and the need to satisfy the demand for food, cause different types of pesticides to be used indiscriminately, causing them to be dispersed into ecosystems by wind and water currents, representing a serious environmental problem. For this reason, it is important to apply effective technologies for the elimination of pesticides from water bodies. In the present research, heterogeneous photocatalysis using ZnO as a photocatalyst was applied to evaluate the degradation of methamidophos in contaminated water prepared in ultrapure water and river water. Considering the working parameters of 3 g/L of zinc oxide, a concentration of 50 mg/L of methamidophos, with constant agitation of 300 rpm, temperature 25 ± 2 °C and a natural pH, methamidophos degradation percentages of 86.66 % and 57.96 % were achieved in ultrapure water and river water, respectively. The chloride, sulfates, nitrates, and nitrites anions present in the river water could be responsible for the decrease in the effectiveness of the photocatalytic process. The mathematical models that best describe the degradation process were the pseudo-second order model and the Elovich model.

The unsustainable use of natural resources, in particular soil degradation and pollution, is one of the main factors contributing to the climate and biodiversity crisis. The European Union has outlined a new European Green Deal, whose objectives include increasing the overall quality of the agri-food chain in relation to environmental sustainability, focusing on reducing the use of pesticides and increasing the share of organic in overall production. A Nexus thinking perspective is applied to analyse this topic over a 50-year time horizon (2010–2060) for the agricultural system of the Basilicata Region (Southern Italy), represented by the TIMES Land-WEF, an optimizing, bottom-up energy-technology model, built to investigate the interactions and interrelations between water, energy food and land. The novelty of this modelling approach is the choice of land use as the guiding parameter of the optimization process. The main objectives of the Farm to Fork Strategy are modelled as system constraints and the scenario analysis allows to characterise their effects on the evolution of the agricultural system over the examined time. The results show that the pesticide reduction constraint leads to an increase in land use by organic crops from 24.6 % to 32.4 % in 2060. In particular, this is due to the increased contribution of cereal, forage, olive growing crops, permanent meadows and pastures, which lead to a 46 % reduction in irrigation water consumption. On the other hand, the reduction in inorganic fertilizers is not accompanied by a significant increase in organic crops, but resulted in the reduction of cereal crops.

In p-MFCs living plants photosynthesize within a bio-electrochemical circuit. The plant exudes organic waste material from the roots. In the rhizosphere, bacteria consume these wastes by oxidizing them in contrast to the atmosphere that reduces it. This redox reaction along with photosynthesis can be harnessed as bioelectricity. In this work, the plant Withania somnifera (L.) Dunal was used for generating bioelectricity from the root exudates and organic matter available in the soil. An open circuit voltage of 930±21 mV was achieved between multiple cycles of operation. The cell voltage further increased to 1260±140 mV with enrichment in the form of discards from vegetable matter. The peak recorded voltage was 1400 mV. Graphite fibre felt electrodes ensured uniform microbial growth with power densities that were achieved at 57 mW/m² and 84 mW/m² with and without enrichment respectively. ATR-FTIR demonstrated complete degradation of specific compounds attached to the carbon matrix in the soil along with the polysaccharide content from the enrichments. Additionally, this work also monitored the changes in soil pH and its homogeneity, the impact of photosynthetically active radiation, humidity, and the presence of CO₂ in the air, and how it affects plant growth and ultimately the microbes at the rhizosphere which accounted for the bioremediation and the resultant bioelectricity production. SEM imaging provided additional evidence that the presence of electrochemically active soil bacteria, an anaerobic environment, and electrode characteristics are crucial for the development of conductive biofilms.

Among the problems most severe for the environment is the pollution of aqueous solution, specifically the creation of threats connected to hazardous heavy metals. In some rural places, it is hardness and chlorides that make groundwater or surface water dangerous in terms of the level of toxins. The requirement of hardness and chlorides is influenced because, in large quantities, when it comes to the quality of drinking water, it causes disease. Water is hazardous to the eyes because of its alkaline nature, inhalation organs, and skin problems. The more hardness and chlorides and related irritations there are, the larger the share. A naturally occurring physiochemical mechanism called biosorption enables certain biomass to passively adsorb hardness and chlorides into the biomass's cellular structure. In the lab, five distinct biosorbents were created, including parthenium, rice husk, rapeseed straw, sawdust, and egg cells, in that order. The parthenium biosorbents turned out to be the most successful biosorbents, despite the fact that each biosorbents has a different level of effectiveness in eliminating hardness and chlorides from water. By using the plant based biomass of parthenium, 65 % of chloride removal with 80 % of hardness removal was obtained. Having identified the best biosorbents, we optimized their parameters and took water samples from different sources. In chlorides removal over parthenium biosorbents, the optima dosage of biosorbents is 3.8 g, temperature is 35 °C, pH is 7, contact time is 120 min and optima agitation speed is 120 rpm. In hardness removal over parthenium biosorbents, the optima dosage of biosorbent is 5.4 g, temperature is 35 °C, pH is 6.5, contact time is 90 min and agitation speed is 150 rpm. Once the chlorides and hardness ions are removed from the water by the utilized biosorbents, the biosorption process may be homo cost effective through the regeneration and reuse of the biosorbent.

Water scarcity poses a critical global challenge, especially in arid and semi-arid regions. This paper introduces an innovative nexus approach to mitigate this issue through the integration of hydro panels in buildings, exploiting solar energy and atmospheric humidity to generate clean water. We offer a comprehensive review of the hydro panel technology's current state, exploring its potential, implementation challenges, and alignment with Sustainable Development Goals (SDGs) through a bibliometric analysis. Our findings highlight a significant uptick in research on sustainable building technologies, positioning hydro panels at the nexus of solutions for water scarcity. Despite their promise, our analysis reveals a scarcity of focused research on hydro panels, indicating an emerging interest in leveraging smart city frameworks for environmental sustainability. The paper contributes by defining the technological trajectory and identifying gaps in existing research, emphasizing the hydro panels' potential to transform water accessibility in arid regions, especially when integrated with other sustainable technologies such as solar photovoltaic (PV) systems. This review not only underlines hydro panels as a novel solution but also paves the way for future investigations into their broader application within the nexus of sustainable urban development.

The bulk electrical system, a critical infrastructure for societal functionality, must meet the electricity demands of end-users sustainably, economically, and in compliance with standards. The concept of power system resiliency has gained significant attention as vulnerabilities and potential attacks could lead to substantial losses. This paper distinguishes power system resiliency from reliability through a detailed literature review. It discusses the development of quantitative metrics from operational and infrastructural perspectives to better understand this emerging concept. We categorize the threats into natural disasters and cyber threats, evaluating their impacts on power system components. The integration of smart grid technologies—including demand response, electric vehicles, distributed generation, energy storage systems, and microgrids—is explored to demonstrate how they enhance resilience against external shocks. This review not only offers a comprehensive analysis of load restoration techniques through smart grid practices but also identifies future challenges, such as adapting to increasingly severe climate conditions, advancing cybersecurity measures to match evolving threats, and ensuring the scalability of resilient systems to meet growing energy demands. These challenges highlight the necessity for innovative research and strategic planning to strengthen power systems against a broad spectrum of emerging threats. This work serves as a critical reference for researchers and planners dedicated to enhancing resiliency strategies.

Cooking is the most energy-intensive activity in the household sector. In developing countries, it accounts for about 90% of the total domestic energy use. With this, knowledge of its dynamics in terms of energy choice and use is imperative. This study explored the nexus between household dynamics and cooking energy choice in Kaduna State, Northwestern Nigeria. Data were collected from 400 households with the aid of a structured questionnaire following a multi-stage sampling approach. Descriptive statistics was used to analyze the data and a multinomial logit regression model was employed to assess the impact of household factors on the choice of primary cooking energy. The results from the descriptive analysis depict charcoal as the most used cooking energy in the surveyed area, followed by fuelwood and Liquified Petroleum Gas (LPG). These choices are influenced by cost, accessibility, and availability. Furthermore, the results from the multinomial logit regression analysis indicated that the choice of cooking energy is significantly influenced by household factors such as household size, household income, occupation of household head, marital status, age, and education of the main cook, and the household head. These findings can be crucial for policymakers and organizations working towards promoting clean and sustainable energy, climate change mitigation, and the reduction of household air pollution.