Fuel Cell Generator Research Articles

Organic Waste for Bioelectricity Generation in Microbial Fuel Cells: Effects of Feed Physicochemical Characteristics

Food waste (FW), piggery waste (PW), and activated sludge (AS) were investigated as potential organic feeds for bioelectricity generation in laboratory-scale microbial fuel cells (MFCs). The MFCs fed by FW gained the highest maximum power density at 7.25 W/m3, followed by those fed by PW at 3.86 W/m3 and AS at 1.54 W/m3. The tCOD removal in the FW-, PW-, and AS-MFCs reached 76.9%, 63.9%, and 55.22%, respectively, within a 30-day retention time. Food waste, which resulted in the highest power density and tCOD removal, was selected for a series of following tests to investigate the effects of some physicochemical properties of organic feed on the performance of MFCs. The effect of feed particle size was tested with three controlled size ranges (i.e., 3, 1, and <1 mm) in MFCs. A smaller feed particle size provided a higher power density of 7.25 W/m3 and a tCOD removal of 76.9% compared to the MFCs fed with organic waste with a larger particle size. An increment in feed moisture from 70% to 90% improved the maximum power density from 7.2 to 8.5 W/m3, with a 17.5% enhancement, and improved the tCOD removal from 75.8% to 83.3%, with a 10.0% enhancement. A moderate C/N ratio of approximately 30/1 maximized the power density and COD removal (7.25 W/m3 and 81.73%) in the MFCs compared to C/N ratios of 20/1 (4.0 W/m3 and 64.14%) and 45/1 (4.38 W/m3 and 71.34%).

Current Advances with Potential Role of Nanotechnology in Generation of Fuel Cells and Solar Cell Batteries

Current Advances with Potential Role of Nanotechnology in Generation of Fuel Cells and Solar Cell Batteries

Techno‐Economic Modeling of Diverse Renewable Energy Sources Integration: Achieving Net‐Zero CO2 Emissions

Integrating renewable energy sources (RES) into power systems presents significant challenges due to their diverse nature and operational characteristics. This study addresses these challenges through an innovative strategy that simulates solar and wind farms, storage systems, fuel cell generators of hydrogen energy (via electrolysis), and hydrogen storage, all governed by an intelligent controller. Alongside a mathematical model defining the system's dynamics, a multi‐objective optimization model is employed, exploring the system's operational, financial, and environmental impacts. While the mathematical model has limitations, the advanced model captures the system's dynamic behavior with exceptional precision. This intelligent simulation simplifies the complex interrelationships between various resources in the system, highlighting the viability of RES integration for enhanced benefits. Multi‐objective optimization of a real case study of Iowa 240‐Bus power system in the Midwest United States has resulted in an annual savings of $126 147.8, along with a significant CO2 reduction of 951 035.6 kg compared with the basecase. The total annual energy costs, including capital costs and electricity sales, are reported to be $157 430.4, and the total annual CO2 emissions are −4453.8 kg. Financial indicators highlight an annual cost reduction of 10.3% and an annual emission reduction of 100.5%. The simple and detailed project break‐even years are 18 and 1, respectively, with the project savings to cost minimization scenario ratio at 1.04. The optimization process efficiently handled a complex problem involving 5921 iterations, 299 247 variables, 11 854 discrete variables, and 342 167 equations, completing the entire operation in 12.7 s. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Utilization of Spent Coffee Grounds for Bioelectricity Generation in Sediment Microbial Fuel Cells.

This study examined the utilization of spent coffee grounds with different aqueous extraction methods for the bioelectricity generation from coastal benthic sediment through a sediment microbial fuel cell (SMFC) system. Different methods for the aqueous extraction of SCGs were evaluated, including rinsing and drying of the SCG (SMFC-CRD), immersion, rinsing and drying (SMFC-CRID), drying alone (SMFC-CD), and untreated SCG (SMFC-C). The caffeine concentration in the SCG was significantly reduced using pretreatments, with SMFC-CRID achieving the lowest concentration of 0.021 ± 0.001 mg/g. SMFC-CRD contributed to the generation of the highest current density of 213.7 mA/m2 during closed-circuit operation and exhibited the highest power density of 96.9 mW/m2 in the polarization test, due to the suitable caffeine content of 0.275 ± 0.001 mg/g in the SCG. This study could provide a cost-effective method for reusing SCGs (i.e., 128 g) while generating bioelectricity as an alternative energy source. These results suggest that pretreatment with SCGs is essential for achieving optimal power density and reducing the caffeine concentration in the SMFC system.

Dynamic Behavior of an Hybrid Wind – Fuel Cell Generation System: Active and Reactive Power Control

This paper reports the investigation on a detailed model of a real wind farm together with a fuel cell generation system based on hydrogen. The modeled wind farm is made up of squirrel cage induction machines and the developed fuel cell model is based on solid oxide type. The aim of the work is to analyze the symbiosis between the wind generation and a centralized energy storage system based on hydrogen for a particular wind farm embedded in the electric power system. With this aim, it has been developed an active and reactive power control system and it has been proposed an strategy for the generation of the reference current of the fuel cell.

Dynamic Control of Fuel Cell Powered Water Pumping Station

An efficient renewable green energy system consisting a hydrogen PEM-fuel cell as an energy sources is simulated and studied in this paper. The proposed green scheme has four separate key components. The first is the green power generation source. The second is the interfacing DC-DC converter used to connect green power generator fuel cell to the load bus. The third is a common DC interface-bus where the generated energy is collected in a DC form. The fourth comprises all interfacing error driven controllers and novel modulated green plug power filter (GPPF) used to reduce ripple variations and stabilize the common DC-Bus voltage. In this paper, the novel multi-loop error driven dynamic controller scheme is implemented for speed control of the PMDC motor. This multi-loop controller comprises three basic loops, the main supplementary dynamic momentum loop to ensure fast dynamic and minimum current and torque ripple content. The proposed fuel cell generation scheme provides efficient and optimum dynamic operation to enhance system performance and secure energy supply. The proposed integrated hybrid system with all subsystems has been simulated using the Matlab Simulink/Sim-Power software environment and validated for voltage stabilization, efficient utilizations and enhanced power quality under different operating conditions, sudden load excursions, despite the non-linear volt-ampere characteristic of the fuel cell DC generator source.

3D Porous Sponge/Carbon Nanotube/Polyaniline/Chitosan Capacitive Bioanode Material for Improving the Power Generation and Energy Storage Performance of Microbial Fuel Cells

Anode materials play a crucial role in the performance of microbial fuel cells (MFCs) in terms of power output. In this study, carbon nanotube (CNT)/polyaniline (PANI)/chitosan (CS) composites were prepared on a porous sponge matrix. The high electrical conductivity of CNTs, the capacitive behavior of PANI, and the biocompatibility of CS were leveraged to enhance the electricity generation and energy storage capabilities of MFCs. Experimental results demonstrated that the MFC with the modified anode achieved a maximum power density of 7902.4 mW/m3. Moreover, in the charging–discharging test, the stored electricity of the S/CNT/PANI/CS anode was 16.38 times that of the S/CNT anode when both the charging and discharging times were 30 min. High-throughput sequencing revealed that the modified composite anode exhibited remarkable biocompatibility and selective enrichment of electrogenic bacteria. Overall, this study presents a novel approach for developing composite MFC anode materials with energy storage functionality.

Research into the operating modes of a stand-alone dual-channel hybrid power system

<abstract> <p>The article describes the development and simulation of a stand-alone hybrid power system based on a variable-speed diesel generator and a hydrogen fuel cell generation system. The goal of the research was to investigate the electromagnetic processes of this power system, which supplies power to autonomous energy consumers with varying load demand. MATLAB Simulink was used to simulate the proposed hybrid power system and check its operating capacity. The results of the simulation include the dependencies of current and voltage changes in the critical components of the hybrid system at stepwise load rate changes. In the future, the developed models and simulation results will allow researchers to select semiconductor devices and create microprocessor-based control systems for electric power installations that meet specific requirements. The dual-channel power system can provide a required power output of 3 kW when powered by a diesel generator and 1 kW when powered by a hydrogen fuel cell. At the same time, the total harmonic distortion (THD) at a load between 100 W and 3 kW varies within acceptable limits between 3.6% and 4.4%. It is worth noting that these higher power complexes can be incorporated into stand-alone electrical grids as well as centralized distribution systems for power deficit compensation during peak loads.</p> </abstract>

Investigating the Impact of Hydrogen Gas Moisture Content on Electricity Generation in PEM Fuel Cells

In the realm of energy sources, non-renewable fossil fuels, such as petroleum derivatives, continue to pose a significant threat to our planet. Currently, hydrogen energy, derived from renewable sources, is under extensive research, primarily due to its high efficiency, versatile applications, and zero carbon emissions. Hydrogen gas has become an indispensable alternative energy source owing to its numerous advantages. The technology that enables efficient utilization of hydrogen gas as an energy source is fuel cells, with Polymer Electrolyte Membrane Fuel Cells (PEM Fuel Cells) being the most significant advancement in this field. In this study, anode and cathode moisture levels were investigated by experimental study on the obtained efficiency of PEM fuel cell performance. Pure hydrogen and oxygen gases were used in the anode and cathode sections of the experiment, respectively. The test stand and a 6 cell 35 watt fuel cell with 9 cm2 active area were used for the test. Temperature and water accumulation, especially humidification in PEM fuel cells, can be achieved by keeping the hydrogen flow, oxygen flow and battery temperature under control. In the experimental study, the fuel cell humidification rate is gradually increased by keeping the flow and line temperature constant. 30% - 35% - 40% - 45% - 50% - 55% - 60% - 65% - 70% of the results obtained in the voltage, amperage and their effects on watts. As a result of the experimental study, humidification rate has a significant effect on the performance of PEM fuel cell. With the increased humidification temperature, the performance of the installed system increased significantly and nominal values were found. However, it is observed that the performance decreases after a certain period of time in the values higher than 60%.

MSC converter with optimized input current ripple for fuel cells applications

This article focuses on the analysis of a newly introduced DC-DC converter structure suitable for applications in fuel cell generation systems, the Modified Series Capacitor (MSC) converter. An interleaved-type converter with high voltage gain. The converter was proposed with a particular PWM scheme in which their two transistors operate with equal duty cycle, but the switching signals are 180° out of phase, and it uses two equal inductors. This article suggests a different way to design and operate the MSC converter with unequal inductors and unequal duty cycles. The primary benefit of the proposed approach with independent duty cycles and inductances is that it allows for the application of a numerical optimization algorithm to minimize the converter's input current ripple without the need to increase the stored energy in inductors. For example, it was possible to reduce one of the two inductors while maintaining (or even improving) the power quality of the input current. To prove the concept, an experiment was set up, executed, and confirmed.

Untreated vs. Treated Carbon Felt Anodes: Impacts on Power Generation in Microbial Fuel Cells.

This research sought to enhance the efficiency and biocompatibility of anodes in bioelectrochemical systems (BESs) such as microbial fuel cells (MFCs), with an aim toward large-scale, real-world applications. The study focused on the effects of acid-heat treatment and chemical modification of three-dimensional porous pristine carbon felt (CF) on power generation. Different treatments were applied to the pristine CF, including coating with carbon nanofibers (CNFs) dispersed using dodecylbenzene sulfonate (SDBS) surfactant and biopolymer chitosan (CS). These processes were expected to improve the hydrophilicity, reduce the internal resistance, and increase the electrochemically active surface area of CF anodes. A high-resolution scanning electron microscopy (HR-SEM) analysis confirmed successful CNF coating. An electrochemical analysis showed improved conductivity and charge transfer toward [Fe(CN)6]3-/4- redox probe with treated anodes. When used in an air cathode single-chamber MFC system, the untreated CF facilitated quicker electroactive biofilm growth and reached a maximum power output density of 3.4 W m-2, with an open-circuit potential of 550 mV. Despite a reduction in charge transfer resistance (Rct) with the treated CF anodes, the power densities remained unchanged. These results suggest that untreated CF anodes could be most promising for enhancing power output in BESs, offering a cost-effective solution for large-scale MFC applications.

A study on public acceptance of hydrogen portfolio standard for renewable energy expansion: Comparative analysis of hydrogen production mix plans

To reduce greenhouse gas (GHG) emissions and achieve carbon neutrality, worldwide governments are establishing various policies and systems for the diffusion of renewable energy. Hydrogen fuel cell (HFC) is evaluated as a next-generation energy source as it can supplement the existing renewable energy sources, while providing stable energy supply and demand. To address low HFC generation share, the Korean government introduced the world's first Hydrogen Portfolio Standard (HPS) into the energy market, where public acceptance is crucial for the implementation of such policies. Thus, this study analyzed the public preference and acceptance for HPS through a discrete choice experiment. Although the public accepted the HPS itself, they preferred a higher proportion of fuel cell generation when the fuel cell was operated through clean hydrogen (blue/green hydrogen). Specifically, the marginal willingness to pay values for a 10% increase in fuel cell generation when changing from grey hydrogen to blue hydrogen or green hydrogen were estimated to be USD 1.94 and 2.97, respectively. Further, the acceptance of green hydrogen-based HPS rises along with the expansion in the HFC generation share. Thus, to expand the fuel cell generation in the national energy mix, transition to a clean hydrogen-based energy system should be attached.

Simultaneous Degradation of Penoxsulam with Power Generation in Microbial Fuel Cells

Simultaneous Degradation of Penoxsulam with Power Generation in Microbial Fuel Cells

Synthetic Biology Toolkit for a New Species of Pseudomonas Promissory for Electricity Generation in Microbial Fuel Cells.

Microbial fuel cells (MFCs) offer sustainable solutions for various biotechnological applications and are a crucial area of research in biotechnology. MFCs can effectively treat various refuse, such as wastewater and biodiesel waste by decomposing organic matter and generating electricity. Certain Pseudomonas species possess extracellular electron transfer (EET) pathways, enabling them to transfer electrons from organic compounds to the MFC's anode. Moreover, Pseudomonas species can grow under low-oxygen conditions, which is advantageous considering that the electron transfer process in an MFC typically leads to reduced oxygen levels at the anode. This study focuses on evaluating MFCs inoculated with a new Pseudomonas species grown with 1 g.L-1 glycerol, a common byproduct of biodiesel production. Pseudomonas sp. BJa5 exhibited a maximum power density of 39 mW.m-2. Also, the observed voltammograms and genome analysis indicate the potential production of novel redox mediators by BJa5. Additionally, we investigated the bacterium's potential as a synthetic biology non-model chassis. Through testing various genetic parts, including constitutive promoters, replication origins and cargos using pSEVA vectors as a scaffold, we assessed the bacterium's suitability. Overall, our findings offer valuable insights into utilizing Pseudomonas spp. BJa5 as a novel chassis for MFCs. Synthetic biology approaches can further enhance the performance of this bacterium in MFCs, providing avenues for improvement.

Topology and Control of Fuel Cell Generation Converters

Fuel cell power generation is one of the important ways of utilizing hydrogen energy, which has good prospects for development. However, fuel cell volt-ampere characteristics are nonlinear, the output voltage is low and the fluctuation range is large, and a power electronic converter matching its characteristics is required to achieve efficient and stable work. Based on the analysis of the fuel cell’s characteristic mechanism, maximum power point tracking algorithm, fuel cell converter characteristics, application and converter control strategy, the paper summarizes the general principles of the topology of fuel cell converters. In addition, based on the development status of new energy, hydrogen energy is organically combined with other new energy sources, and the concept of 100% absorption system of new energy with green hydrogen as the main body is proposed to provide a reference for the development of hydrogen energy.

Energy Management Control for Dual Power Source Powered Electric Vehicle

This paper presents a Proposed Energy Management Strategy (PEMS) for an electric vehicle powered by a fuel cell generator with a storage system based on a super capacitor. A PEMS is needed for hybrid sources in order to manage the energy flow from different sources to supply the power train. Thus, for simulating the studied system under two driving cycles, the MATLAB/Simulink has been used. The obtained results proved a good efficiency of the developed PEMS by minimizing as possible fuel consumption of the main power source.

Effects of External Resistance, New Electrode Material, and Catholyte Type on the Energy Generation and Performance of Dual-Chamber Microbial Fuel Cells

In this study, the effects of an external resistance, new electrode material, and non-conventional catholyte on the energy generation and performance of a dual-chamber MFC were evaluated. Ten different resistances (15 Ω–220 kΩ), hydrophilically-treated graphene and graphite electrodes, and a 0.1 M HCl solution as a catholyte were assessed. The results showed that greater energy generation and power density were achieved at an external resistance of 2 kΩ and internal resistance between 2 and 5 kΩ on average; meanwhile, the greatest coulombic efficiency was obtained at the lowest external resistance evaluated (15 Ω). Therefore, it is recommended to operate the MFCs at the external resistance between 2 and 5 kΩ to ensure the maximum power generation of the dual chamber MFCs. Regarding the two electrode materials evaluated as an anode and cathode, hydrophilically-treated graphene was found to be a much better material to enhance the energy production and performance of the MFC system; therefore, its use is suggested in experimental and practical applications. On the other hand, the use of HCl as a catholyte enhanced the performance of MFC (constant and steady potential and greater coulombic efficiency) in most cases.

Assessment of Graphite, Graphene, and Hydrophilic-Treated Graphene Electrodes to Improve Power Generation and Wastewater Treatment in Microbial Fuel Cells.

In this study, graphite, graphene, and hydrophilic-treated graphene electrodes were evaluated in a dual-chamber microbial fuel cell (DC-MFC). Free-oxygen conditions were promoted in anodic and cathodic chambers. Hydrochloric acid at 0.1 M and pH 1.1 was used as a catholyte, in addition to deionized water in the cathodic chamber. Domestic wastewater was used as a substrate, and a DuPontTM Nafion 117 membrane was used as a proton exchange membrane. The maximum power density of 32.07 mW·m-2 was obtained using hydrophilic-treated graphene electrodes and hydrochloric acid as catholyte. This power density was 1.4-fold and 32-fold greater than that of graphene (22.15 mW·m-2) and graphite (1.02 mW·m-2), respectively, under the same operational conditions. In addition, the maximum organic matter removal efficiencies of 69.8% and 75.5% were obtained using hydrophilic-treated graphene electrodes, for hydrochloric acid catholyte and deionized water, respectively. Therefore, the results suggest that the use of hydrophilic-treated graphene functioning as electrodes in DC-MFCs, and hydrochloric acid as a catholyte, favored power density when domestic wastewater is degraded. This opens up new possibilities for improving DC-MFC performance through the selection of suitable new electrode materials and catholytes.

Optimization of solid oxide fuel cell power generation voltage prediction based on improved neural network

Abstract This paper proposes a method for predicting the generation voltage of a solid oxide fuel cell based on the data results of a stand-alone solid oxide fuel single cell simulation model under ideal conditions, with the aim of improving the generation efficiency and extending the service life of the solid oxide fuel cell. In this paper, a modified back propagation (BP) neural network algorithm is used to improve the prediction accuracy of the solid oxide fuel cell generation voltage by using the whale algorithm to optimize the BP neural network model to improve its convergence and achieve the effect of improving the prediction accuracy. First, the characteristics of the independent solid oxide fuel cell are introduced and simulated. Second, the long short-term memory network model, linear regression network model and BP neural network are simulated and compared, and the results show that the BP neural network prediction model is more accurate and can be optimized and improved. Finally, the BP neural network is optimized and simulated using the whale algorithm, and the simulation results show that the method has better convergence and higher prediction accuracy than the traditional BP neural network prediction model.

Anode Modification with Fe2O3 Affects the Anode Microbiome and Improves Energy Generation in Microbial Fuel Cells Powered by Wastewater.

This study investigated how anode electrode modification with iron affects the microbiome and electricity generation of microbial fuel cells (MFCs) fed with municipal wastewater. Doses of 0.0 (control), 0.05, 0.1, 0.2, and 0.4 g Fe2O3 per the total anode electrode area were tested. Fe2O3 doses from 0.05 to 0.2 g improved electricity generation; with a dose of 0.10 g Fe2O3, the cell power was highest (1.39 mW/m2), and the internal resistance was lowest (184.9 Ω). Although acetate was the main source of organics in the municipal wastewater, propionic and valeric acids predominated in the outflows from all MFCs. In addition, Fe-modification stimulated the growth of the extracellular polymer producers Zoogloea sp. and Acidovorax sp., which favored biofilm formation. Electrogenic Geobacter sp. had the highest percent abundance in the anode of the control MFC, which generated the least electricity. However, with 0.05 and 0.10 g Fe2O3 doses, Pseudomonas sp., Oscillochloris sp., and Rhizobium sp. predominated in the anode microbiomes, and with 0.2 and 0.4 g doses, the electrogens Dechloromonas sp. and Desulfobacter sp. predominated. This is the first study to holistically examine how different amounts of Fe on the anode affect electricity generation, the microbiome, and metabolic products in the outflow of MFCs fed with synthetic municipal wastewater.