Feasibility assessment of hybrid solar photovoltaic-biogas generator based charging station : a case of easy bike and auto rickshaw scenario in a developing nation

The popularity of electric vehicles (EVs) is increasing day by day in the modern world. The charging of EVs from grid-connected charging stations causes a considerable power crisis in the grid. Integrating renewable energy resources (RESs) with conventional energy sources in the power grid is now considered feasible to reduce peak power demand and the inevitable emission effect. Hence, this paper presents an energy solution for EV charging with two RESs, namely, solar photovoltaic (PV) and biogas. HOMER software is utilized to analyze the potency and functionality of solar PV and biogas-based EV charging stations. The proposed system consists of a solar PV system, two biogas engine generators, and a bidirectional converter with battery storage. The variation of different costs, such as net present cost (NPC), initial cost, and cost of energy (COE) for different solar PV systems (3 kW, 4.5 kW, 6 kW, and 9 kW), are analyzed in HOMER software. The 4.5 kW solar PV system is finally selected as the NPC, initial cost, and COE are $93,530,$19,735, and $0.181, respectively, which is efficient. The system’s lifetime is 25 years, where an initial 12 years is required to overcome the system cost, and the remaining 13 years will provide financial benefits. The study also illustrates the effect of solar irradiance, biomass, and the change in the load of the energy management system. The techno−economic analysis shows that the proposed scheme can be an effective energy solution. The emission of greenhouse gases (GHGs), such as CO2, CO, SO2, and NOX, is reduced considerably compared to other existing techniques. The study is expected to be beneficial in renewables-based EV charging systems with techno−economic and environmental feasibility

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

An Assessment on Additive Manufacturing Technique to Fabricate Integral PEM Fuel Cell/Electrolyser Component

Additive Manufacturing (AM) is a reliable technique to build multifunctional components with any complex geometry. The present paper assesses the role of two vital AM techniques, namely Selective Laser Sintering (SLS) and Selective Laser Melting (SLM) in the fabrication of integral Polymer Electrolyte Membrane (PEM) fuel cell/electrolyser component. Thus, the paper integrates the state-of-the-art technologies, namely additive manufacturing and fuel cell/electrolyser engineering. The US department of energy (US-DoE) target can be comprehensively accomplished for the fuel cell/electrolyser stack components in a cost-effective approach. The fundamental PEM fuel cell/electrolyser components considered in the present study are the bipolar plate and gas diffusion layer (GDL)

A Novel Technique to Manufacture Carbon-free Gas Diffusion Layer for Polymer Electrolyte Membrane Fuel Cell Application by a Selective Laser Sintering (3D Printing)

A Gas Diffusion Layer (GDL) is an integral component of a PEM fuel cell stack, which plays a significant role in determining its performance, durability and the dynamic characteristics. An ideal GDL function to simultaneously transport three of the five essential elements, namely gas, water and heat involved in the electrochemical reaction. In addition, it also transports the electron produced in the electrochemical reaction and serves as an armour to safeguard the membrane (Nafion), which is a delicate and most expensive component of the PEM fuel cell stack. However, the conventional carbon-based GDL materials suffer from degradation issues during PEM fuel cell operation, and the predominant one is the electrochemical voltage oxidation. The electrochemical degradation is due to the oxidation of the carbon present in the carbon paper to carbon dioxide especially at voltages greater than 0.207 V on a standard hydrogen electrode (SHE). Operating a PEM fuel cell stack at a low voltage (<0.207 V) is not practically possible since it can severely aggravate the operating efficiency and power density of the PEM fuel cell stack. Incorporating a GDL that is free from carbon can be a promising solution to circumvent these issues about the electrochemical oxidation. Also, the conventional GDL manufacturing technique had a tedious and complicated process, which involves multiple stages. These multiple production stages also led to its high manufacturing costs and increased lead-time. The proposed research work is estimated to address both these issues of GDL durability and manufacturing costs. The additive manufacturing method incorporating selective laser sintering (SLS) technique aims to provide a comprehensive solution to address both these issues. The concept of SLS is that the laser beam robotically scans the composite powder (base and conductive powder) at points in a space defined by a 3D model, fusing and subsequently binding the composite material together to create a solid-state structure. Thus, SLS can be a favourable route to fabricate a carbon-free GDL as well as to reduce its manufacturing costs and lead-time. At the end of the experimental investigation, holistic characterisation studies were performed to have a general insight on the characteristics of the proposed material. Valuable information is extrapolated from the characterisation studies, which can assist, to fine-tune the material selection and SLS process parameter. In addition, ground-breaking findings from the perspective of the structural and functional relationship of the proposed GDL specimen had been made considering the first principles of the diverse field of engineering. Though the performance based on the experimental results are inferior, it gives us the buoyancy that the proposed proof of concept can be a promising route to fabricate durable and cost-effective gas diffusion layers based on the critical observations of the SLS process

A Novel Technique to Manufacture Carbon-free Gas Diffusion Layer for Polymer Electrolyte Membrane Fuel Cell Application by a Selective Laser Sintering (3D Printing)

A Gas Diffusion Layer (GDL) is an integral component of a PEM fuel cell stack, which plays a significant role in determining its performance, durability and the dynamic characteristics. An ideal GDL function to simultaneously transport three of the five essential elements, namely gas, water and heat involved in the electrochemical reaction. In addition, it also transports the electron produced in the electrochemical reaction and serves as an armour to safeguard the membrane (Nafion), which is a delicate and most expensive component of the PEM fuel cell stack. However, the conventional carbon-based GDL materials suffer from degradation issues during PEM fuel cell operation, and the predominant one is the electrochemical voltage oxidation. The electrochemical degradation is due to the oxidation of the carbon present in the carbon paper to carbon dioxide especially at voltages greater than 0.207 V on a standard hydrogen electrode (SHE). Operating a PEM fuel cell stack at a low voltage (<0.207 V) is not practically possible since it can severely aggravate the operating efficiency and power density of the PEM fuel cell stack. Incorporating a GDL that is free from carbon can be a promising solution to circumvent these issues about the electrochemical oxidation. Also, the conventional GDL manufacturing technique had a tedious and complicated process, which involves multiple stages. These multiple production stages also led to its high manufacturing costs and increased lead-time. The proposed research work is estimated to address both these issues of GDL durability and manufacturing costs. The additive manufacturing method incorporating selective laser sintering (SLS) technique aims to provide a comprehensive solution to address both these issues. The concept of SLS is that the laser beam robotically scans the composite powder (base and conductive powder) at points in a space defined by a 3D model, fusing and subsequently binding the composite material together to create a solid-state structure. Thus, SLS can be a favourable route to fabricate a carbon-free GDL as well as to reduce its manufacturing costs and lead-time. At the end of the experimental investigation, holistic characterisation studies were performed to have a general insight on the characteristics of the proposed material. Valuable information is extrapolated from the characterisation studies, which can assist, to fine-tune the material selection and SLS process parameter. In addition, ground-breaking findings from the perspective of the structural and functional relationship of the proposed GDL specimen had been made considering the first principles of the diverse field of engineering. Though the performance based on the experimental results are inferior, it gives us the buoyancy that the proposed proof of concept can be a promising route to fabricate durable and cost-effective gas diffusion layers based on the critical observations of the SLS process

A Comprehensive Review on Printed Electronics: A Technology Drift towards a Sustainable Future

Printable electronics is emerging as one of the fast-growing engineering fields with a higher degree of customization and reliability. Ironically, sustainable printing technology is essential because of the minimal waste to the environment. To move forward, we need to harness the fabrication technology with the potential to support traditional process. In this review, we have systematically discussed in detail the various manufacturing materials and processing technologies. The selection criteria for the assessment are conducted systematically on the manuscript published in the last 10 years (2012&ndash;2022) in peer-reviewed journals. We have discussed the various kinds of printable ink which are used for fabrication based on nanoparticles, nanosheets, nanowires, molecular formulation, and resin. The printing methods and technologies used for printing for each technology are also reviewed in detail. Despite the major development in printing technology some critical challenges needed to be addressed and critically assessed. One such challenge is the coffee ring effect, the possible methods to reduce the effect on modulating the ink environmental condition are also indicated. Finally, a summary of printable electronics for various applications across the diverse industrial manufacturing sector is presented

A Novel Fuzzy Schema to Control the Temperature and Humidification of PEM Fuel Cell System

The present paper proposes a simple yet effective technique to improve the performance of a practical PEM fuel cell system by tuning the two key operating parameters based on the expert’s rules derived from the literature. The fuzzy rule base is designed to optimally control the temperature and humidification of the two critical parameters governing the fuel cell system performance and dynamics. The modelling of the proposed methodology is presented through the Matlab/fuzzy logic toolbox.</jats:p