Clean Technol., Volume 4, Issue 4 (December 2022) – 27 articles

Xylose Isomerase (XI) is an intramolecular oxidoreductase enzyme and catalyzes the reversible conversion of ketoses and aldoses in addition to the bioconversion of ethanol from xylose in the production of bioethanol from hemicellulose. It has a broad range of industrial applications in the food and pharmaceutical sectors, particularly in the production of the sweetener high fructose corn syrup (HFCS). It is one of the most widely used industrial enzymes after protease. Taking this into consideration, four bacterial XI sources were selected based on growth temperature, i.e., psychrophile, mesophile, thermophile, and hyperthermophile, for analyzing Xylose Isomerase’s structure-function characteristics. It was found that thermophilic XI was structurally less stable than mesophilic and hyperthermophilic XI, whereas structural plasticity ran opposite towards mesophiles. The interaction of xylose isomerase (XI) with two ligands, namely Amino-2-Hydroxymethyl-Propane-1,3-Diol and (4R)-2-Methylpentane-2,4- Diol, was also studied. Mesophilic XI demonstrated better binding affinity with structurally stabilizing amino acids (Ala, Asp, Gly, Leu, and Arg). In comparison, Thermophilic XI showed nearly similar binding affinity with both Amino-2-Hydroxymethyl-Propane-1,3-Diol and (4R)-2-Methylpentane-2,4-Diol. The results of this investigation suggest that thermophilic XI, followed by mesophilic XI, would be the most appropriate for establishing process stability and sustainability in the food industry. Full article

This study evaluates the performance of commercial reverse osmosis (RO) and nanofiltration (NF) membranes for the removal of metal ions from synthetic water and surface water carried from the north-west of Lake Tanganyika in the city of Uvira, in the east of the Democratic Republic of Congo. Metal ion analyses were performed by the standardized ICP-MS and ICP-OES methods. The RO membrane showed higher metal ion rejection in high-concentration solutions (synthetic samples) prepared in the laboratory as well as in low-concentration samples from real raw water collected near Lake Tanganyika. Rejection levels were higher than 98% for Cr³⁺, Pb²⁺, Cd²⁺, As³⁺, Ni²⁺, and Sb⁺³ ions in the synthetic solutions, and 99.2, 98.8, 98.6, 99.2, 98.4, and 98.8%, respectively, in the real samples. The concentrations of metals in the permeate varied depending on the feed concentration and were 0.15 to 1.02 mg/L, 0.33 to 22 mg/L, and 0.11 to 22 mg/L in RO, NF90, and NF270 membranes, respectively. Regarding the NF membranes, the rejection of Cr, Ni, and Cd ions was interesting: 98.2, 97.8, and 92.3%, respectively. However, it was lower for Pb, As, and Sb ions: 76.9, 52.5 and 64.1%, respectively. The flux of NF was 329 to 375 L/m².h, much higher than for RO membranes, which had a flux of 98 to 132 L/m².h. The studied membranes are thus a feasible solution to remove the studied metals from real water sources at low concentrations since they meet the standards of the World Health Organization on specific values assigned to chemicals from industrial sources and human habitation areas where these ions are present in drinking water. Full article

The production of staple articles such as cable ducts offers reductions in resource and production energy consumption if the process is optimized. Side recesses made of polyvinyl chloride (PVC) have already been punched successfully as one of the process steps during the production of cable ducts. However, punching cable ducts made of flame-retardant polycarbonate/acrylonitrile–butadiene–styrene (PC/ABS) is challenging because increased burr and film formation occurs. This study introduces the correct dimensioning of the clearance as a means of reducing the burr and film formation and presents the ideal clearance dimensions. This new process design approach comprises the dimensioning of the clearance and its subsequent successful application. Tools with clearances in the relevant size range were purchased and examined by means of punching tests. The punch-outs were evaluated regarding the quality characteristics, such as the burr, film, cut surface quality, shear droop, and plastic flow characteristics. Excerpts from high-speed recordings were used to assess the punch-outs qualitatively. The burr formation is significantly decreased by the use of a correctly dimensioned clearance, allowing for the crack initiated at the punch side and the crack initiated at the die side to meet perfectly. It is assumed that film formation can be avoided via a significant reduction in the friction or heat input during the punching process. Full article

Battery systems are one of the most important components for the development of flexible energy storage for future applications. These comprise energy storage in both the mobility sector and stationary applications. To ensure the safe operation of multiple battery cells connected in series and parallel in a battery pack, it is essential to implement state of charge (SOC) equalization strategies. Generally, two fundamentally different approaches can be distinguished. On the one hand, these are passive approaches for SOC equalization that are based on including additional Ohmic resistors in a battery back over which equalization currents flow as long as the correspondingly connected cells have different voltages. Despite the simple implementation of such equalization circuits, they have a major drawback, namely wasting stored energy to perform the SOC equalization. This waste of energy goes along with Ohmic heat production, which leads to the necessity of additional cooling for batteries with large power densities. On the other hand, active SOC equalization approaches have been investigated, which allow for an independent charging of the individual cells. Especially, this latter approach has big potential to be more energy efficient. In addition, the potential for a reduction of Ohmic heat production may contribute to extending the lifetime of battery cells. To perform the individual charging of battery cells in an energetically optimal manner, this paper provides a comparison of closed-form optimization approaches on the basis of Pontryagin’s maximum principle and approaches for reinforcement learning. Especially, their accuracy and applicability for the implementation of optimal online cell charging strategies are investigated. Full article

The energy efficiency of fruit and vegetables refrigeration facilities can be increased through the reduction of heat generated by produce (in kWh/kg). Ethylene production in fruit and vegetables is closely linked to their respiration rates. Clean technologies that can reduce ethylene production of fruit and vegetables are needed to relax (increase) the setpoint temperature of cold rooms. The heat produced may be reduced by up to 50% when ethylene concentrations surrounding the produce are reduced from 0.1–1 to 0.001–0.01 μL L⁻¹ during the storage of some vegetables. There is a need to find green alternatives to ethylene scavenging techniques (of high cost and chemical origin) such as, for example, active packaging with encapsulated essential oils. Hence, respiration and ethylene production rates of flat peaches and broccoli were reduced by up to 30–50% with active packaging with essential oils. It would imply a lower produce heat generation of 14–30% with the consequent energy savings in the refrigeration systems of horticultural facilities. Consequently, the potential of essential oils released from active packaging to reduce the energy consumption related to respiratory heat of produce is hereby firstly reviewed and proposed as a clean technology to extend the postharvest life of fruit and vegetables. Full article

The optimal placement of distributed generation (DG) is a critical task for distribution companies in order to keep the distribution network running smoothly. The optimal placement of DG units is an optimization problem. In this paper, minimization of the voltage deviation from flat voltage is considered as an objective function. The self-adaptive Lévy flight-based Jaya algorithm is used as an optimization technique to determine the best location and size of distributed generation units. In the MATLAB environment, the proposed algorithm was implemented on IEEE 15 and PG and E 69 bus distribution systems. According to the simulation results, distribution networks can supply more quality power to customers by minimizing the voltage deviation from the flat voltage profile if the DG units are properly placed and sized. Full article

Higher heating values (HHV) is a very useful parameter for assessing the design and large-scale operation of biomass-driven energy systems. HHV is conventionally measured experimentally with an adiabatic oxygen bomb calorimeter. This procedure is often time-consuming and expensive. Furthermore, limited access to the required facilities is the main bottleneck for researchers. Empirical linear and nonlinear models have initially been proposed to address these concerns. However, most of the models showed discrepancies with experimental results. Data-driven machine learning (ML) methods have also been adopted for HHV predictions due to their suitability for nonlinear problems. However, most ML correlations are based on proximate or ultimate analysis. In addition, the models are only applicable to either the originator biomass or one specific type. To address these shortcomings, a total of 227 biomass datasets based on four classes of biomass, including agricultural residue, industrial waste, energy crop, and woody biomass, were employed to develop and verify three different ML models, namely artificial neural network (ANN), decision tree (DT) and random forest (RF). The model incorporates proximate and ultimate analysis data and biomass as input features. RF model is identified as the most reliable because of its lowest mean absolute error (MAE) of 1.01 and mean squared error (MSE) of 1.87. The study findings can be used to predict HHV accurately without performing experiments. Full article

In this work we analyze numerically different design configurations to be used in a R1234yf DMS cycle coupled with a water source, transcritical CO₂ heat pump for heating applications in the building sector. Specifically, we study the temperature range proposed by a European standard for heating with inlet/outlet water temperatures of: 30 °C/35 °C, 40 °C/45 °C, 47 °C/55 °C and 55 °C/65 °C. Moreover, 25 °C/30 °C is also analyzed which is the range expected for indoor swimming pool water pool heating applications. A water inlet temperature of 10 °C at the evaporator was considered in all of the cases. Results show that depending on the coupling strategy between the DMS cycle and the CO₂ heat pump, optimal COP values obtained can vary up to 30% whereas the optimal operating pressure of the CO₂ cycle can vary up to 8%. A configuration based on splitting the water flow to be heated into the DMS condenser and the gas cooler in a system with IHX was the best option for all the temperature ranges studied. The improvement in the maximum COP values obtained with this configuration ranges between 5% (for swimming pool applications) and 25% (for space heating with 40 °C/45 °C) when compared with the base cycle depending on the water temperature range considered. When this configuration is not considered, the basic transcritical CO₂ with IHX and without DMS was found the best option. Full article

One of society’s major current challenges is carbon dioxide emissions and their consequences. In this context, new technologies for carbon dioxide (CO₂) capture have attracted much attention. One of these is carbon capture and utilization (CCU). This work focuses on the latest trends in a holistic approach to carbon dioxide capture and utilization. Absorption, adsorption, membranes, and chemical looping are considered for CO₂ capture. Each CO₂ capture technology is described, and its benefits and drawbacks are discussed. For the use of carbon dioxide, various possible applications of CCU are described, starting with the utilization of carbon dioxide in agriculture and proceeding to the conversion of CO₂ into fuels (catalytic processes), chemicals (photocatalytic processes), polymers, and building supplies. For decades, carbon dioxide has been used in industrial processes, such as CO₂-enhanced oil recovery, the food industry, organic compound production (such as urea), water treatment, and, therefore, the production of flame retardants and coolants. There also are several new CO₂-utilization technologies at various stages of development and exploitation, such as electrochemical conversion to fuels, CO₂-enhanced oil recovery, and supercritical CO₂. At the end of this review, future opportunities are discussed regarding machine learning (ML) and life cycle assessment (LCA). Full article

The current study explores steam explosion pre-treatment of wood sawdust to develop high-quality biofuel pellets. In order to determine optimized conditions (temperature and residence time) for steam-treated biomass, seven test responses were chosen, including bulk, particle and pellet densities as well as tensile strength, dimensional stability, ash content and higher heating value (HHV). Parameters tested for steam treatment process included the combination of temperatures 180, 200 and 220 °C and durations of 3, 6 and 9 min. Results showed that when the severity of steam pre-treatment increased from 2.83 to 4.49, most of the qualities except HHV and ash content were favorable for steam pretreated materials. The pellet density of pretreated sawdust in comparison to raw sawdust resulted in 20% improvement (1262 kg/m³ for pretreated material compared with 1049 kg/m³ for non-treated material). Another important factor in determining the best pellet quality is tensile strength, which can be as high as 5.59 MPa for pretreated pellets compared with 0.32 MPa for non-treated pellets. As a result, transportation and handling properties can be enhanced for steam pretreated biomass pellets. After optimization, the selected treatment was analyzed for elemental and chemical composition. Lower nitrogen and sulfur contents compared with fossil fuels make steam pretreated pellets a cleaner option for home furnaces and industrial boilers. High-quality pellets were produced based on optimized pre-treatment conditions and are therefore suggested for bioenergy applications. Full article

Electric vehicles, which are primarily powered by lithium-ion batteries, have gained much attention as the future of transportation for their environmental and economic benefits. However, the current economy of lithium-ion battery management is quite linear. A circular economy with reusing and end-of-life recycling of lithium-ion batteries, would reduce the social and environmental costs associated with the mining of metals, decelerate the depletion of natural resources, and prevent the improper management that often accompanies disposal. This research suggests improvements to the end-of-life management of lithium-ion batteries in the US, considering current and emerging recycling technologies, current collection and transportation infrastructure, current reuse applications, and an analysis of the current regulatory policies in place. Along with providing a comprehensive overview of these topics, this research compiles and provides a set of actionable End-of-Life (EOL) management recommendations for the US on policy, infrastructure, and technology. Full article

This paper presents an adsorption cooler (AC) driven by the surplus heat of a solar thermal domestic hot water system to provide cooling to residential buildings. A cylindrical tube adsorber using granular silica gel as adsorbent and water as adsorbate was considered. The AC was modelled using a two-dimensional distributed parameter model implemented in previous adsorption heating and cooling studies. The performance coefficients of the resultant thermally driven cooling system were obtained for a broad range of working conditions. The thermally driven AC was found to have coefficient of performance (COP) of 0.5 and a specific cooling power (SCP) of 44 W·kg⁻¹ when considering condenser, evaporator, and regeneration temperatures of 30 °C, 15 °C, and 70 °C, respectively. Moreover, the results showed that the AC could be used for refrigeration purposes at temperatures as low as 2 °C and that it could also operate during hotter days under temperatures of 42 °C. Full article

Solid waste management (SWM) in rural areas of many low- and middle-income countries (LMICs) represents a critical and underrated topic. However, almost half of the world’s population still lives in rural areas and an adequate SWM is crucial in reducing environmental and health threats. A lack of knowledge and appropriate tools often leads to inappropriate practices such as waste dumping and uncontrolled burning. However, appropriate methods can transform waste into resources and even guarantee a revenue source. This manuscript provides an overview of the state of the knowledge characterising SWM in rural communities of LMICs, analysing common practices and principal issues. Different solid waste fractions are considered. Virtuous approaches are presented, taking into account recent sustainable solutions. Considering that a relevant part of the world population is still living in rural areas, the benefits associated with an appropriate SWM may be enormous. Such activities may improve local conditions from social, environmental and health perspectives; furthermore, they may have a global impact on facing climate change and environmental pollution. Full article

The Brazilian sugarcane industry generates a significant amount of waste each year, which should be properly analyzed and studied to allow an adequate recovery and application supported by the best understanding of its properties. The present work reports the ignition and burnout temperatures of sugarcane bagasse (SCB) obtained after performing a thermal analysis using four different heating rates. The intersection method (IM) and deviation method (DM) were employed to approach the ignition and burnout temperatures of the sugarcane bagasse. The ignition temperatures of the SCB measured from IM are between 250 and 263 °C, and their burnout temperatures are between 357 and 377 °C. The ignition temperature was in the range of 205 °C to 236 °C for the DM. IM is recommended for determining the ignition and burnout temperatures. In TGA, the heating rates in the range of 10 °C·min⁻¹ and 15 °C·min⁻¹ are suggested due to their accuracy and the contribution to timesaving in the analysis. Full article

In the context of a circular economy/zero-waste, the conversion of extractive wastes into new products is of particular importance. At the Grecian Magnesite SA mine (Chalkidiki, N. Greece), millions of tons of waste accumulate in the operation field. To achieve these goals, the effect of caustic calcined magnesia (MgO) at 10, 15, and 20 wt.% was investigated in combination with 0.5, 1, 2.5, and 5 wt.% Fe₂O₃ at 1300 °C and 1600 °C for 120 min. The main refractory properties were determined along with the mineralogical content. The morphological examination has been performed by SEM-EDS analysis. The addition of MgO increases the desired olivine and eliminates the unwanted pyroxenes, causing the formation of magnesium-ferrite and periclase. MgO wt.% addition resulted in the decrease of firing shrinkage at 1300 °C but increased with Fe₂O₃. At 1600 °C, firing shrinkage had a minimum value at the optimum MgO dose. Mechanical strength at 1600 °C achieved a maximum value at the optimum MgO dose plus 5 wt.% MgO and 2.5 wt.% Fe₂O₃ due to sintering process/magnesioferrite formation. These results indicate that MgO and Fe₂O₃ upgrade the refractoriness of magnesite mining wastes due to the diffusion of Fe₂O₃ in MgO excess. Full article

The agricultural industry uses substantial amounts of water (the highest in the world) mostly for irrigation purposes. Rapid population growth and, consequently, growing demand for food have increased the use of pesticide to have higher yield for crops and other agricultural products. Wastewater generated as a result of excessive use of pesticides/herbicides in agricultural industry is becoming a global issue specifically in developing countries. Over 4,000,000 tons of pesticides are currently used in the world annually and high concentrations above their threshold limits have been detected in water bodies worldwide. The generated wastewater (contaminated with pesticides) has negative impacts on human health, the ecosystem, and the aquatic environment. Recently, biodegradable and biocompatible (including plant-based) pesticides have been introduced as green and safe products to reduce/eliminate the negative impacts of synthetic pesticides. Despite positive advantages of biopesticides, their use is limited due to cost and slow interaction with pests compared to chemical pesticides. Pesticides may also react with water and constituents of soil resulting in formation of intermediates having different physical and chemical properties. Diffusion, dispersion, and permeation are main mechanisms for transfer of pesticides in soil and water. Pesticides may degrade naturally in nature; however, the time requirement can be very long. Many mathematical models have been developed to simulate and estimate the final fate of pesticides in water resources. Development of new technologies and environmentally friendly pesticides to reduce water contamination is becoming increasingly important. Full article

In this work, a peroxydisulfate (PDS)-based advanced oxidation process was used for removing diuron from water. The effect of heat and MnO₂ as PDS activators was explored. It was found that diuron degradation obeyed zero-order kinetics in the presence of heat-activated PDS. The relative contribution of MnO₂ to the diuron degradation decreased with the increasing temperature. At the highest temperature investigated, T = 55 °C, complete diuron removal was achieved in less than 75 min. A kinetic model for describing the rate of diuron degradation was proposed and successfully applied to the experimental data. Full article

In the context of the global energy crisis and crucial issues on food, the development and utilization of agrivoltaic (APV) systems could be a way to solve both the energy shortage and agricultural production at the same time and in the same area. As a combination of photovoltaics (PV) and agriculture, agrivoltaics has broad prospects for the future agricultural development of Hungary. Since especially large-scale PV systems can be considered as a potential basis of APV systems, the Kaposvár Solar Power Plant Project in Hungary was analyzed in this study. Two comparative analyses were used: between APV and PV systems, and between APV and apple plantation. An economic model has been developed. The baseline scenario shows that APV systems in current technological and economic conditions are not competitive with PV systems and are also less attractive for agricultural farmers, due to the long return period of the surplus investment cost. By analyzing uncertain factors and seeking possible solutions, the authors’ recommendations for the development, subsidy system and technology might be useful for both farmers and for decision makers to promote APV systems in the future. Full article

Effluent treatment and reuse are essential in order to address the global problem of water scarcity. Additionally, improving the quality of treated wastewater is necessary to reduce its adverse effects on natural water resources and, consequently, on human health. Electrocoagulation and adsorption have been successfully applied separately to treat different wastewaters. Each method has unique benefits, drawbacks, and parameters that affect the effectiveness of treatment. A review of both processes, including their theoretical principles, the effect of operating conditions, and practical applications, is presented to provide an overview of their capabilities. The combination of electrocoagulation and adsorption in a combined process can be used to amplify the advantages of each process while mitigating their limitations. In the present work, the combined process is analyzed in terms of its principles, applications, and integration in a circular economy model. Full article

An “energy evolution” is necessary to manifest an environmentally sustainable world while meeting global energy requirements, with natural gas being the most suitable transition fuel. Covering the ever-increasing demand requires exploiting lower value sour gas accumulations, which involves an acid gas treatment issue due to the greenhouse gas nature and toxicity of its constituents. Successful design of the process requires avoiding the formation of acid gas vapor which, in turn, requires time-consuming and complex phase behavior calculations to be repeated over the whole operating range. In this work, we propose classification models from the Machine Learning field, able to rapidly identify the problematic vapor/liquid encounters, as a tool to accelerate phase behavior calculations. To set up this model, a big number of acid gas instances are generated by perturbing pressure, temperature, and acid gas composition and offline solving the stability problem. The generated data are introduced to various classification models, selected based on their ability to provide rapid answers when trained. Results show that by integrating the resulting trained model into the gas reinjection process simulator, the simulation process is substantially accelerated, indicating that the proposed methodology can be readily utilized in all kinds of acid gas flow simulations. Full article

Electricity has become one of the most important factors contributing to both the livelihoods of individuals and global economic development. Most electricity generation is still derived from burning fossil fuels that contribute to environmental degradation. The aim of this research, through innovative design, was to create clean circular technology through the utilization of electronic devices that control and send optimally timed commands to two 72-volt batteries (DC) that store and distribute energy. This new form of electric power generation was adapted to be used with a three-way differential gear system. The speed of transmission was adjusted, and shaft rotation was connected to a 7.5 kw/h DC power motor with two 15 kw/h alternators in three phases to generate high torque power at the desired rate of 3000 RPM and electricity. The first set of alternators generated the electrical energy to be distributed. The circuit system of battery set one was used for storage and slowly fed to the motor, which was kept continuously running for hours. The second alternator distributed the generated voltage to the secondary battery, which stored backup power and provided the main power to the grid. This system is especially appealing for those looking to improve energy efficiency and contribute to the green economy, as this system can be applied to power charging stations for electric vehicles or used as a backup power source for buildings. Full article

The rapid increase in the integration of renewable energy sources into the electrical grid is posing new challenges for the dynamic responses due to the global inertia reduction. In this regard, the impact on frequency stability of such reduction and the potential support from wind power have been investigated lately. However, it is well-known that the variability of wind power and its reduced inertia may not be enough to handle the power unbalance. Energy storage systems (e.g., batteries) may provide the required additional flexibility to ensure proper response. In this paper, an analysis of how the different control loops for frequency support on wind power and batteries interact and perform is presented. To gain insights from the different impacts, a sensitivity analysis comparison for frequency regulation through (i) inertia and droop control of a variable speed wind turbine and (ii) battery is performed. The analysis was carried out through simulations using the well-known 4 generator 2-area model adapted to include a wind farm. From a battery perspective, its ramping capabilities were varied to provide frequency regulation. The paper shows how, depending on the control parameters and battery size, the frequency response may even become unstable due to interactions of the various pieces of technology. Thus, it shows that coordinated actions, control optimization and grid status among different actors on the grid (as battery and wind) is required for stable operation. Full article

Transition to low emission transportation and cleaner cities requires a broad introduction of low- and zero-carbon alternatives to conventional petrol- and diesel-powered vehicles. New-generation gas buses are a cost-effective way to reduce local air pollutants from urban transportation. Moreover, major greenhouse gas (GHG) savings may be achieved using biogas as the power source. The main objective of this research was to investigate CH₄ and other gaseous emissions of a biogas-fueled urban bus equipped with a three-way catalyst (TWC) in real-world conditions. The study focused on emissions from a six-year-old gas-powered city bus, supplementing emission data from aging bus fleets. Impaired CH₄ oxidation and NO_x reduction were observed in the catalyst after its service life of 375,000 km–400,000 km. The main reason for low CH₄ and NO_x conversion over the TWC was concluded to be the partial deactivation of the catalyst. Another critical issue was the fluctuating air-to-fuel ratio. The results show that the efficiency of exhaust after-treatment systems should be closely monitored over time, as they are exposed to various aging processes under transient driving conditions, leading to increased real-world emissions. However, the well-to-wheels (WTW) analysis showed that an 80% GHG emission benefit could be achieved by switching from diesel to biomethane, giving a strong environmental argument for biogas use. Full article

The quest for novel nanoscale materials for different applications necessitates that they are easy to obtain and have excellent physical properties and low toxicity. Moreover, considering the ongoing environmental impact of noxious chemical waste products, it is important to adopt eco-friendly approaches for nanoparticle synthesis. In this work, a natural polymer (medium molecular weight chitosan) derived from chitin was employed as a reducing agent to obtain gold nanoparticles (AuNPs) with a chitosan shell (AuNPs@CS) by a microwave oven. The chitosan is economically viable and cost-competitive in the market showing also nontoxic behavior in the environment and living organisms. The synthesized AuNPs@CS-FITC NPs were fully characterized by spectroscopic and microscopic characterization techniques. The size distribution of NPs was about 15 nm, which is a suitable dimension to use in biomedical applications due to their high tissue penetration, great circulation in blood, and optimal clearance as well as low toxicity. The prepared polymer-capped NPs were further functionalized with a fluorescent molecule, i.e., Fluorescein-5-isothiocyanate (FITC), to perform imaging in the cell. The results highlighted the goodness of the synthesis procedure, as well as the high internalization rate that resulted in an optimal fluorescence intensity. Thus, this work presents a good sustainable/green approach-mediated polymer nanocomposite for various applications in the field of diagnostic imaging. Full article

Hydrogen generation through electrolyzers has gained a growing interest from researchers and industries to decarbonize transportation and electricity production. The performance of electrolyzers is strongly dependent on their operating conditions, such as the supply current, temperature, and pressure. To meet near-zero emissions, the electrolyzer must be supplied by low-carbon energy sources. Therefore, renewable energy sources must be considered. However, these sources are strongly linked with the weather conditions, so they have a high dynamic behavior. Therefore, this article is focused on the investigation of the effects of these dynamic solicitations on the electrical and thermal performance of electrolyzers. In this study, a proton exchange membrane (PEM) has been chosen to carry out this investigation. Experimental tests have been performed, emphasizing the relationship between the electrical and thermal performance of the PEM electrolyzer. The purpose of this work is to provide an optimal scenario of the operation of the electrolyzer under dynamic solicitations and consequently, to decrease the degradation of the electrolyzer. Full article

With the widespread use of lithium-ion batteries in a wide range of consumer electronics products, the CE industry has undergone a dramatic shift. The Li-ion battery has emerged as the heart of electric cars, and the focus has now shifted to the automotive sector. Liquid crystal displays have evolved over time to meet the demands of automobiles. International research groups and the performance of production electric vehicles are used to discuss and inform vehicle-driven battery targets. There is still a lot of room for improvement in terms of energy, life expectancy, cost, safety, and fast-charging capabilities for LIBs suited for the automotive sector. In this study, a review of lithium-ion battery applications in electric vehicles is presented. Full article

The DigiMon project aims to develop and demonstrate an affordable, flexible, societally embedded, and smart digital monitoring early warning system for any subsurface CO₂ storage field. The societal embeddedness level (SEL) assessment is a novel methodology which provides insight into the societal requirements for technological innovation to be deployed. The SEL assessment framework was applied in four case studies, concerning CCS development in Norway, the Netherlands, Greece, and Germany. The resulting societal embeddedness levels of CCS, on a scale of 1–4, were SEL 3 in Norway with considerable progress towards level 4, followed by the Netherlands with SEL 2 with several initiatives towards offshore demonstration projects, and then by Greece and Germany with SEL 1. The outcomes of the SEL assessments show which societal requirements have been met in current CCS developments and which ones should be improved for CCS deployment. They also show that monitoring currently is a regulatory requirement as part of permitting procedures, while it may alleviate community concerns on safety, provided that it has certain attributes. The insights from the four national case studies are further used in the DigiMon project to develop the innovative societal embedded DigiMon monitoring system. Full article