Tank Size Research Articles

Assessing rainwater harvesting scenarios to mitigate potable water storage needs in Algerian individual houses under intermittent supply.

Urban areas in Algeria are increasingly suffering from water scarcity due to climate change and rapid urbanization, prompting the government to introduce an intermittent water supply system. This situation requires households to store potable water during supply interruptions. This study investigates the potential of rainwater harvesting (RWH) to reduce the need for such storage in single-family homes in the municipality of Beni-Mared (north of Algeria). Through five simulated scenarios: "Current" which represents the existing situation without RWH; "Maximum" in which all available rainwater is captured; "Switch" in which the existing potable water storage tanks are used for rainwater; "Optimal" in which the size of the storage tanks and efficiency are balanced; and "Outdoor" in which the focus is on rainwater for external purposes such as watering. The results show that the "Maximum" scenario has the greatest potential, as it reduces the need for potable water storage by up to 84.5%, although it requires large and potentially expensive tanks. The "Optimal" scenario offered a practical solution in which a 2.7 m³ tank covers up to 33% of the storage. The "Switch" scenario, where existing tanks were repurposed, reduced storage requirements by 15.07%, while the "Outdoor" scenario, designed for external uses, achieved a more modest reduction of 5.85% to 6.71%. These results demonstrate the importance of implementing an adapted RWH approach supported by a comprehensive development strategy, community involvement and financial support to effectively address water scarcity in Algeria.

Improving the performance of hot water storage tanks using chimney type heaters

Hot water storage tanks (HWST) are high energy consumption devices. One way of reducing energy consumption is improving thermal stratification of the HWST. Improving thermal stratification will supply hot water faster for users, reduce the energy they consumed, increase efficiency in solar collectors or heat exchanger. In this work, the electrically heated HWST is led under investigation to improve the thermal stratification by imposing a chimney over the heating element to accelerate the top layer temperature by natural convection. Various tank sizes (38, 50, 62, and 75 litres) were investigated. The chimney height (HC), chimney diameter (DC) and chimney natural flow area (Df= 9.5, 2.5 and 1.5 cm) were also analysed to find the optimal chimney. The experiments revealed that using chimney in the HWST will accelerate the natural circulation to the upper layer in the storage tank. This will reduce the amount of energy required to perform the same operation without a chimney. Using chimney type heaters (CTH) in the HWST is favorable especially when tanks volume to heating element power increases. The entropy generation and distorted exergy of the system were improved by using CTH, thus the available reversable work increases. High hot water temperatures were attained in a shorter time which favorite such HWST. Higher efficiencies in case of solar heat collectors (due to lower cold-water temperatures in the bottom layers). Dynamic mode of CTHHWST represents a significant issue which needs detailed investigation which is currently under investigation.

A hybrid approach based energy management of hybrid energy systems with efficient economic model

ABSTRACT This paper proposes a hybrid AHO-SNN-based energy management (EM) of hybrid energy systems (HES) with an efficient economic model. The proposed hybrid method is combined with the Archerfish Hunting Optimizer (AHO) and Spiking Neural Network (SNN). Commonly, it is named as AHO-SNN technique. The major aim of the AHO-SNN method is the efficient economical modeling of HES and the study of sizing and EM. The comprehensive approach for describing the ideal size EM system (EMS) combination for HES is presented in this paper. The HESs, like fuel cell (FC), electrolyzer (EL), PV, battery energy system (BES), diesel generator (DSL), and hydrogen tank (HT). To determine the ideal size-EMS combination, this new EMS is employed to re-use the analytical as well as economic sizing. The AHO-SNN technique is implemented in the MATLAB software and is compared to various existing techniques. The AHO-SNN method provides an optimum outcome than the existing Particle Swarm optimization (PSO), Heap based optimizer (HBO), and Wild horse optimizer (WHO) methods. The power comparison of the existing technique HBO achieved power is 30 W, WHO is 20 W, WHO is around 10 W. In the proposed technique, the power generated is 40 W, which is way higher than the existing techniques. After implementing the integrated framework, the size of PV is cut in half, from 140 to 60 kW, which reduces the electrolyzer and the size of the hydrogen tank in also cut in half. In addition to a 35% decrease in diesel generator working hours and a 40% reduction in the leveled energy cost, PV degrades at a rate of 0.5%.

Study on the performance temporal variation of rainwater harvesting systems based on the dynamic change of rainfall pattern and domestic water demands

Rainwater harvesting systems (RWHs) in buildings are benefits in alleviating urban water scarcity. However, climate change and changes in building water demand affect the expected performance of RWHs over their life cycle. Previous studies have only focused on the adaptability of RWHs to climate change without considering the changes in building water demand. To address this issue, this study explores the impact of combined changes in precipitation patterns and domestic water demand on the water-saving efficiency of RWHs over their 25-year life cycle based on historical observations. Three cities in Japan were selected as case studies. The results indicate that during 25-year life cycle of RWHs, precipitation in different cities in Japan shows an increasing trend, while domestic water demand shows a decreasing trend. Such trend resulted in a change of -2.90–4.02% in the water-saving efficiency of the established RWHs and a change of -2.90–3.82% in the theoretical optimal water-saving efficiency, and these effects were greater in RWHs in buildings with high non-potable water demands. Therefore, RWHs in buildings with low non-potable water demand can appropriately reduce the rainwater tanks, while RWHs in buildings with high non-potable water demand must increase the rainwater tank size to eliminate this adverse effect. Furthermore, both reductions in domestic water demand and increases in precipitation have a positive effect on the water-saving efficiency of RWHs. However, when both domestic water demand and precipitation increase or decrease simultaneously, the change in water-saving efficiency of RWHs is related to the non-potable water demand of the building. This study can provide data support and theoretical evidence for the further implementation of RWHs under climate change, and can help stakeholders to optimize and update RWHs to ensure system feasibility.

Critical diameter for a single-tank molten salt storage – Parametric study on structural tank design

Molten salt thermal energy storage (TES) is a cost-effective option for grid-connected storage in both concentrating solar power (CSP) plants and retrofitted thermal power plants in a multimegawatt scale. Current systems use two tanks (hot and cold), but future systems may use a single tank with a transient temperature profile (hot in the top and cold in the bottom) to reduce costs and space. However, the structural and mechanical design of large-scale molten salt single-tank storages at 560 °C has not been fully explored, and the impact of increasing the operating temperature to 620 °C is still uncertain. The challenge presented by a single tank is the existence of a temperature profile that results in a varying thermal expansion of the tank shell along its height. In the case of larger tanks, this discrepancy can reach a magnitude of centimeters, which in turn gives rise to bending moments. To the best of our knowledge, this study addresses the issue of bending stresses in large-sized high-temperature tanks with thermal stratification for the first time. The modelling approach is applied to single-tank CSP TES systems as a case study to evaluate the constraints imposed by tank size and wall thickness.With the help of experimentally validated numerical methods, it is revealed that a low thermocline thickness can be a limiting factor for large tank diameters. It is shown that the temperature has a major influence on maximum possible tank size: if the operating temperature is raised from 560 °C to 620 °C, the permitted tank diameter is significantly reduced when using the same tank wall material. A possible approach is to use a more heat resistant steel for 620 °C. Results of the parametric study show that designing a single tank below a critical diameter only requires a moderate increase of the wall thickness compared to the two-tank system with constant temperature profiles. Based on this parametric study a formula for the critical tank diameter is developed and presented in this work. The paper concludes with recommendations on how increased wall stresses can be addressed by an appropriate design.

Comprehensive case study on the technical feasibility of Green hydrogen production from photovoltaic and battery energy storage systems

AbstractThe growing demand for alternative energy sources to alleviate environmental impacts highlights the need to move from fossil fuels to renewable energy. This study demonstrated the technical feasibility of using a solar photovoltaic (PV) system for the production of green hydrogen. This research examined electrical and power data from a PV plant in Irecê, Bahia, using open data sources to provide insights into the production of green hydrogen from renewable sources. The system mainly depends on the use of a renewable source, PV solar energy, integrated with batteries, electrolyzers, and hydrogen tanks. Electrolyzer, battery, and hydrogen tank sizing analysis for optimal hydrogen production was effectively conducted using HOMER Energy software. The predicted system topology prioritizes a local DC network, optimizing efficiency for electrolyzers that have inherently low efficiency. The electrolyzer simulation involves initial Python‐based sizing and comprehensive sizing with HOMER Energy software, ensuring accuracy within a 10% discrepancy limit. This highlights the importance of analytical calculations and optimization software for sizing more complex systems.

Removal of heavy metals from mine water using a hybrid electrocoagulation-ceramic membrane filtration process

Mining operations must account for increasingly stringent wastewater discharge limits for various contaminants, such as heavy metals and suspended solids. In the treatment of metal-bearing wastes, electrochemical processes, including electrocoagulation (EC), are gaining popularity. At large scales, EC processes can be hindered by considerable amounts of flocculants and by sedimentation tank sizes required to properly operate. This work sought to address these concerns by evaluating EC in mine water treatment using a pilot system coupled with ceramic membrane microfiltration (MF) and ultrafiltration (UF). The use of MF and UF after EC allows for the removal of suspended solids without needing a flocculation-sedimentation process. EC evaluation was performed using field samples of mine water from a North American concentrator. Under optimal conditions, EC removed over 95 % of Cr, Co, Cu, Fe, Mn, Ni, Pb, Ti and Zn from the mine water. Effluent from EC was used as feed in MF and UF processes with ceramic membranes. The tested membranes rejected 100 % of suspended solids from the EC effluent. Permeate from the membranes was free of solids and possessed turbidities of 0.05–0.15 NTU. Filtrate from the hybrid process satisfied environmental regulations for heavy metal concentrations, offering new opportunities for reuse or discharge. The hybrid process applied in this work can thus be used in mining operations to safely discharge their water, and/or to increase their water recirculation due to environmental concerns and water shortage.

Optimization of design and operation of a digestate treatment cascade for demand side management implementation

Sustainable chemical engineering through demand side management (DSM) and renewable feedstock integration e.g. in biorefineries are key to optimizing the use of fluctuating energy resources and minimizing environmental impact while conserving resources. This contribution presents the results of the economic evaluation of integrating DSM into biofuel biorefineries through a dynamic simulation approach. A previously developed decision support tool for DSM implementation was extended to describe the size of intermediate buffer tanks as a function of oversizing up- and downstream processes. Design optimization of the process cascade determined the oversizing that allows the optimal balance of operational cost reduction through flexibility and capital cost increase through oversizing. Scheduling optimization validated the results of the steady-state optimization and show that, by considering interactions between processes, buffer tank capacity can be reduced, while increasing DSM potential.

Implementation and barriers to waterless care: a questionnaire study of infection prevention and control practitioners, clinicians, and engineers

Water and wastewater in healthcare settings are recognized to represent a risk to patients. However, waterless care has not been widely implemented in UK healthcare settings. To identify barriers to implementation of waterless care. A questionnaire study of infection prevention and control (IPC) practitioners, non-IPC clinicians, and estates managers and engineers was undertaken. Alternatives to water present challenges in perceived acceptability to patients, particularly cleansing wipes for bathing and dry shampoo. There are concerns about cleansing wipes in terms of storage, disposal, sustainability and contamination during manufacture. Estates and engineering concerns include relative water tank size for water turnover and clinical disruption due to works. Further work is required on acceptability of reduced water scenarios and patient views but the results of this questionnaire provide a grounding for sentiment from healthcare workers on waterless care.

Effect of Water Tank Size and Supply on Greenhouse-Grown Kidney Beans Irrigated by Rainwater in Cold and Arid Regions of North China

In response to water scarcity in the Bashang area of northwest Hebei Province, a cold and arid region in north China, and to address the diminishing groundwater levels caused by pumping irrigation, this study investigated the impact of rainwater tank size and water supply on kidney beans production in greenhouses under various precipitation scenarios to determine the production potential and development strategies for regional precipitation resources. Under the background of average annual precipitation, kidney bean yield increased with increasing reservoir volume and shorter irrigation cycles. Under a 4-day irrigation cycle, the water demand satisfaction rate of kidney beans reached 100% water demand when the rainwater tank size was 15.7 m3. Against the wide variation in multi-year regional precipitation from 1992 to 2023, the annual effect of rainwater harvest was simulated using precipitation data collected 20 years with an 80% precipitation guarantee rate. The average minimum yield reduction rate obtained was 9.4%, and the corresponding minimum rainwater tank size was 29.5 m3. By superimposing the rainwater harvested in the shed and nonshed areas, the volume of the reservoir without yield reduction could be reduced to 20.0 m3. The sum of discharged and inventory water was much greater than the water scarcity in each water supply situation. Simulating and analyzing the effect of the relationship between rainwater tank size and water supply on rainwater harvesting in regional farmland by year provides important data affecting the construction of regional rainwater storage facilities and water supply efficiency. To achieve a high, stable yield of kidney beans grown in a greenhouse with shed film and shed area rainwater harvesting in north China, 2.6 m3 supplementary groundwater irrigation is still needed during the annual growing season.

Implementing a rainwater harvesting system in an arid region with an LCA approach

AbstractThe purpose of this study is to compare the life cycle assessment and reliability of different rainwater harvesting (RWH) systems in residential buildings in Tehran for a period of 50 years. Four main scenarios based on the number of stories (1, 2, 3, and 4) each including five sub-scenarios based on the size of the rainwater storage tank (2.5m3, 5m3, 7.5m3, 10m3, 12.5m3) and one using solely tap water were defined. Simapro software was used for life cycle assessment which was carried out using the endpoint and midpoint methods. The collected rainwater is assumed to be merely used to fill flush tanks and if it cannot satisfy this demand, tap water will be used. The results show that in an arid city like Tehran, collecting rainwater does not even come close to meeting non-potable water needs, and in most scenarios, tap water must be used for more than half of the days. Despite the low reliability of RWH systems, they perform better than tap water in most environmental impact categories because the processes used to produce tap water have the highest contribution to environmental damage. Among the sub-scenarios that use rainwater for flush tank demands, in almost all environmental impact categories, sub-scenarios that collect more rainwater (higher storage tank sizes) have better performance. The performance of sub-scenarios that use more rainwater is better in the endpoint environmental categories of ecosystems and human health; however, this trend is the opposite in the impact category of resources. Graphical abstract

Assessment of rainwater harvesting potential from rooftops in Jordan's Twelve Governorates.

Rooftop rainwater harvesting (RRWH) offers a potential solution to Jordan's pressing water scarcity problems. Yet, its feasibility and benefits necessitate a thorough assessment, particularly as existing studies on the subject are outdated and often constrained by limited scope or small data sets. To this end, our study assessed the potential of RRWH in Jordan's 12 governorates, utilizing historical rainfall data from 1987 to 2018 and official statistics on population and rooftop areas. The analyses used the Ripple Method and Water Balance Model to determine potential harvestable water volumes, potential water-saving percentages, and optimal tank sizes under different scenarios (i.e., using rainwater to meet the total consumption or only for toilet flushing). The findings reveal that Jordan has a total potential for rooftop rainwater harvesting amounting to 23.74 Mm3/year, corresponding to 4.54% of the total water demand. Should RRWH be implemented across all rooftops, the projected financial savings for Jordan could range from $170 million to $678 million. Among the governorates, Irbid and Amman have the highest potential, with estimated yields of 7.754 Mm3 and 8.453 Mm3 per year, respectively. Based on the best results for the scenario where harvested rainwater is only used to flush toilets, the optimal tank sizes for storing rainwater were estimated to be 2.7 m3 and 2 m3 per household in Ajlun and Irbid, respectively. For a regularized case (October-May), a payback period of 12.5-24 years based on desalination cost was found for an RRWH system capable of meeting thrice the flushing needs of a household. RRWH was showcased as a sustainable solution to Jordan's water scarcity, emphasizing the necessity for broader implementation.

Lignin extraction in chemical pulp mills: The role of flexible operation

Lignin extracted from black liquor in chemical pulp mills can potentially replace fossil carbon feedstocks in fuels and materials, thereby increasing the economic and environmental added values of woody biomass. However, since lignin extraction reduces the electricity generation of the mill, the added value depends on the characteristics of the electricity market in which the mill operates. In this study, a model mill is exposed to two different electricity price profiles: the low and steady prices of south-central Sweden in Year 2019; and the high and volatile prices of the same region in Year 2022. For the model mill, investments in lignin extraction designed to increase pulp production are economically viable and have low levels of sensitivity to electricity price levels and price volatility. The viability of lignin extraction without increased pulp production depends on the relationship between the electricity and lignin prices. With stable electricity prices, or steady mill operation, a rule-of-thumb holds that for lignin extraction to be viable, the lignin price (€/t) must be 1.8-times the average electricity price (€/MWh) plus 40 €/t for the supply of chemicals. With volatile electricity prices and flexible operation of the recovery boiler, the mill can shift the loss in electricity sales to low-price hours, thereby saving 15–70 % of the operational costs of lignin extraction, as compared to steady operation. This effect can be further enhanced by increasing the capacity of the lignin extraction process or extending the size of the black liquor storage tank. The proposed flexibility measures allow the market-integrated pulp mill to export lignin to replace fossil carbon supplies in other sectors, while supporting the electricity system during hours with high demand and low supply.

Exploring variations in the weight, size and shape of liquid hydrogen tanks for zero-emission fuel-cell vessels

We report an exploration of liquid hydrogen (LH2) tank technology, determining if improving LH2 tank weight, multiplicity or shape enables more hydrogen to be stored on hydrogen vessels. The improvements investigated are well beyond the current LH2 technology state-of-the-art. The platform for this study is a monohull H2 Baseline research vessel powered 100% by hydrogen.Regarding weight reductions, we found that the research vessel does not benefit significantly from large weight reductions of the LH2 tanks. A 50% reduction in mass of the inner pressure vessel led to a 3.1% reduction in the total research vessel weight. Reducing the LH2 tank weight to the asymptotic limit of zero results in a 7.1% reduction in the overall research vessel weight. This maritime application, while benefitting from a reduction in LH2 tank weight, is not a strong driver for LH2 tank weight improvements.The two large LH2 tanks of the H2 Baseline Vessel can be replaced with a multitude of smaller LH2 tanks. In two Multiplicity design variants, the total amount of stored LH2 was ∼5–9% less than that of the H2 Baseline Vessel, which does not motivate conducting the needed R&D that would drive the technology to smaller high-performing LH2 tanks.We did find a significant benefit to improving the shape of LH2 tanks, towards prismatic tanks that would better match the vessel hullform. Considering a “Shape Variant” that included space-consuming features such as tank connection spaces, manifolding and ventilation, we found a 26% improvement in stored LH2 compared to the H2 Baseline Vessel. The large improvement in storage capacity could warrant further LH2 tank R&D that can enable high performing prismatic LH2 tanks, such as pressure vessel steel developments allowing for higher strength/ductility at 20 K, improved insulation systems, methods for efficiently building prismatic tanks with insulation systems fit for 20 K service and flare-less techniques for managing heat leak (venting).The results are reviewed considering the current regulatory restrictions as well as prevailing limitations in LH2 tank manufacturing.

Comparative life cycle assessment of various hydrogen supply methods from Australia to the Republic of Korea in environmental and economic aspects

With the increasing importance of decarbonization to prevent global climate change, hydrogen supply has received considerable attention from several countries, including Korea and Japan, due to the growing demand for the implementation of a hydrogen economy. This study conducted a comprehensive analysis on hydrogen supply methods from Australia to the Republic of Korea in environmental and economic aspects using a life cycle assessment (LCA). The blue hydrogen produced in Australia was considered for import to the Republic of Korea via ocean shipping. The study analyzed the holistic environmental effects in the life cycle of hydrogen ocean transport for various types of hydrogen storage methods (CH2, LH2, LOHC, LNH3, and LNG), as well as alternative marine fuels (MGO, LNG, LPG, CH2, LH2, LNG-LH2, MeOH, and LNH3) for ship transportation. Environmental impact performance was presented in terms of global warming potential (GWP), acidification potential (AP), photochemical ozone creation potential (POCP), eutrophication potential (EP), and particulate matter (PM). For the environmental results, sensitivity studies were conducted to analyze the effects of operating distance and cargo tank size when shipping hydrogen via ocean transport. Additionally, the GWP results of the transportation of green hydrogen and ammonia were compared with those of blue hydrogen and ammonia transport. A cost analysis was performed for the overall processes of hydrogen ocean transport, and the results were included in the study with the estimated hydrogen price for each transportation method.

Scaling study of miniaturised continuous stirred tank reactors via residence time distribution analysis and application in the production of iron oxide nanoparticles

Magnetically agitated miniaturised continuous stirred tank reactors (mCSTRs) are an attractive platform for the intensification of chemical reactions involving solids by combining active stirring and intensified heat and mass transfer due to their small dimensions. This work investigated the operation of mCSTRs at flowrates up to 60 ml/min (space time of 3 s per tank) as a means of increasing the throughput of fast reactions. Investigation of the residence time distribution under varying operational (flowrate, stirrer rotational speed) and reactor geometrical (stirred volume, stir bar size) parameters, showed deviation from the ideal CSTR behaviour at increasing flowrates, which could be mitigated by keeping the stir bar length close to the tank diameter, increasing stirrer rotational speed, and using larger tank sizes. Assembling mCSTRs into cascades did not amplify non-ideal behaviour and allowed narrowing the residence time distribution at high throughput. Various configurations of mCSTR cascades were evaluated for the synthesis of iron oxide nanoparticles (IONPs) via iron chloride co-precipitation with NaOH, demonstrating the importance of residence time distribution (RTD) control when increasing the throughput of nanoparticle production. Using a 5 × 3 ml mCSTR cascade for the core formation followed by a 5 × 3 ml mCSTR cascade for deagglomeration/stabilisation, the IONP flow synthesis was scaled successfully, producing high quality nanoparticles (7.3 ± 2 nm) at 60.5 ml/min (l/h scale).

System Optimization and Operating Strategy of Single-Stage Air Source Heat Pump with Thermal Storage to Reduce Wind Power Curtailment

Wind power generation has increased in China to achieve the target of decreasing CO2 emissions by 2050, but there are high levels of wind curtailment due to the mismatch between electricity supply and demand. This paper proposes a single-stage air source heat pump coupled with thermal storage for building heating purposes. The main objective is to find the proper system designs and operating strategy, which can help to avoid peak demand periods while obtaining minimized running costs and reduced wind energy curtailment. Dynamic simulations were performed using TRNSYS to investigate its use in a typical office building based on an actual electricity tariff, wind power, and meteorological data. The proper system designs, including the tank size and thermal storage temperature, were determined to maximize the system’s performance. It was found that a proper combination of the two parameters exists for a specific application. Further, results showed that the use of auxiliary electric heating is necessary for single-stage air source heat pumps to participate in a wind curtailment reduction. The operating strategy of the system was also studied. Results indicate that by implementing a proper operating strategy, non-renewable power consumption can be reduced by 11% for the studied building, with a total wind power utilization of 3348 kWh during the heating season while still satisfying the heating demands of users. These findings can contribute to the green and low-carbon development of the building industry and further enhance the grid’s accommodation capacity for renewable energy sources.

Defective flow space limits the scaling up of turbulence bioreactors for platelet generation

To complement donor-dependent platelets supplies, we previously developed an ex vivo manufacturing system using induced pluripotent stem cell (iPSC)-derived expandable immortalized megakaryocyte progenitor cell lines (imMKCLs), and a turbulent flow bioreactor to generate iPSC-derived platelets products (iPSC-PLTs). However, the tank size of the bioreactor was limited to 10 L. Here we examined the feasibility of scaling up to 50 L with reciprocal motion by two impellers. Under optimized turbulence parameters corresponding to 10 L bioreactor, 50 L bioreactor elicited iPSC-PLTs with intact in vivo hemostatic function but with less production efficiency. This insufficiency was caused by increased defective turbulent flow space. A computer simulation proposed that designing 50 L turbulent flow bioreactor with three impellers or a new bioreactor with a modified rotating impeller and unique structure reduces this space. These findings indicate that large-scale iPSC-PLTs manufacturing from cultured imMKCLs requires optimization of the tank structure in addition to optimal turbulent energy and shear stress.

Better integrating battery and fuel cells in electric vehicles

AbstractThis paper presents an innovative approach to enhancing the range of battery electric vehicles (BEVs) through the integration of a hydrogen fuel cell range extender. By combining the high energy efficiency of BEVs with the rapid refueling capability and extended range of hydrogen fuel cells, this hybrid system addresses the limitations of current electric vehicles in scenarios demanding longer driving ranges or quicker refueling options. Our study encompasses both experimental and theoretical analyses, leading to the proposal of a BEV configuration that includes a smaller battery complemented by a fuel cell range extender. The conventional fuel cell electric vehicle (FCV) examined relies exclusively on hydrogen fuel and features a minimal battery without plug‐in functionality, resulting in suboptimal energy economy. In contrast, our proposed BEV with a fuel cell range extender employs a larger battery capacity of 12 to 16 kWh alongside a downsized fuel cell stack and reduced hydrogen tank size. This configuration significantly improves energy recovery during braking and extends electric operation, thereby doubling the vehicle's energy economy. The proposed system not only enhances energy efficiency but also reduces the weight and volume of the overall energy storage system. Preliminary estimates suggest that the miles‐per‐gallon equivalent (MPGe) of this hybrid solution could exceed 140 over the US EPA certification cycle, outperforming existing PHEVs, BEVs, and FCVs.

Partial discharge localization in power transformer tanks using machine learning methods

This paper presents a comparison of machine learning (ML) methods used for three-dimensional localization of partial discharges (PD) in a power transformer tank. The study examines ML and deep learning (DL) methods, ranging from support vector machines (SVM) to more complex approaches like convolutional neural networks (CNN). Multiple case studies are considered, each with different attributes, including sensor position, frequency content of the PD signal, and size of the transformer tank. The paper focuses on predicting the PD location in three-dimensional space using single-sensor electric field measurements. Various aspects of each method are analyzed, such as the input signal, core methodology, correlation coefficient between the predicted location and the actual location, and root mean square error (RMSE). These features are discussed and compared across the different methods. The results indicate that the CNN model exhibits superior performance in terms of location accuracy among the methods considered.