Zhe Sun, Ruixue Cao, Manhong Huang et al.

Journal of Renewable and Sustainable Energy • 2015

A new method combined microbial fuel cell (MFC) with polycrystalline silicon solar cell (PSSC) was exploited to investigate its energy generation and its performance on the removal of hexavalent chromium (Cr(VI)). The open circuit voltage (Vocv) of MFC-PSSC could reach 3.540 V, which, to our best knowledge, was the maximum Vocv of MFC reported. The power density of MFC-PSSC was 754.4 mW·m−2 under simulated solar light irradiation, which increased by 990% compared to 76.2 mW·m−2 of a single MFC. The concentration of Cr(VI) in MFC was 17.06 mg·l−1, which was around 12.6 times higher than that in the MFC-PSSC (1.35 mg·l−1) after operation of 48 h. The concentration of chemical oxygen demand in MFC (264 mg·l−1) was around 6 times higher than that in the MFC-PSSC (44 mg·l−1) after operation of 48 h. This study would provide a new insight into the energy generation from MFC coupling with solar cells, and provide exciting opportunities for the utilization of solar energy and bio-energy.

C. Baroux, M. Detrilleaux, G. Demazy

Volume 2: Mgmt. Low/Interm. Level Waste; Spent Fuel; Economics/Analyses for Waste Mgmt.; Radiological Characterization/Application Release Criteria; Panel Sessions; Solid Waste Reduction/Treatment; Current Activities in Central/Eastern Europe; Environmental Remediation Technology; LL/ILW; HLW/Spent Fuel; Chernobyl; D&D Waste; Performance Assessment; MOX and Spent UOX; D&D Nuclear Reactors; Decommissioning of Other Nuclear Facilities • 2001

Abstract Spent nuclear fuel has been stored at the DOEL power station in Belgium in dual-purpose metal casks since 1995. The casks were procured from TRANSNUCLEAIRE by SYNATOM to meet the operational demands for on-site dry storage solutions for fuel arising from the four PWR reactors at DOEL. The TN 24 type of cask was chosen and a range of different cask types were developed. The initial requirement was for dual purpose cask to contain fuel from the DOEL units 3 and 4, these having similar fuel types but different lengths, and thus two new members of the TN 24 family were developed; the TN 24 D and TN 24 XL with capacities of 28 and 24 SFA’s. These casks were licensed as B(U) fissile packagings with approval certificates granted by the French and validated by the Belgium competent authorities for the transport configurations. Both cask designs were also analyzed by TRANSNUCLEAIRE in their storage configurations to ensure that the criteria for safe interim storage could be met. Since 1995, a total of 18 TN 24 D and TN 24 XL casks have been loaded with spent fuel assemblies with an average burn-up of 40,000 MWd/tU. SYNATOM subsequently decided to purchase further casks for DOEL 3 and 4 fuels with higher enrichments, higher burn-ups and shorter cooling times. TRANSNUCLEAIRE developed the TN 24 DH and TN 24 XLH casks within the similar envelope size and weight limits. The increase in performance was achieved by an in-depth optimization of each design in terms of radiation shielding, heat transfer and criticality safety. This paper shows how this optimization process was undertaken for the TN 24 DH and TN 24 XLH casks, 16 of which have been ordered by SYNATOM. DOEL 1 and 2 units use much shorter PWR fuel and it was decided to ship the fuel to unit 3 with an internal transfer cask because the handling limitations in the DOEL 1 and 2 pool prohibited the loading of a high capacity dual purpose transport/storage cask. The TN 24 SH cask was subsequently designed for DOEL 1 and 2 PWR fuel with a capacity of 37 assemblies and nine of there casks have been ordered by SYNATOM. The casks are fitted with monitoring devices to detect any change in the performance of the double metal O ring closure system and none of the casks has shown any deterioration in leaktightness. This paper examines the operation experience of loading and storing more than 30 TN 24 dual purpose casks and compares the performance with design expectations.

Chien-Chang Wu, Tsung-Lin Chen

Energies • 2020

In this paper, a novel control circuit that can connect fuel cell (FC) modules in parallel is proposed, which is particularly useful when the employed FCs have different electrical characteristics. Conventional methods (e.g., DC/DC converters) are not applicable in such situations because they cannot regulate the power output of each source in a parallel-connected topology. Consequently, the uniformity requirement of FCs increases and becomes costly. In contrast to existing methods, the proposed method adopts a novel power-feedback method to control the power output of each FC module under both rated conditions and load changes, which in turn determines the operating point of each FC module. Therefore, the uniformity requirement can be relaxed. For proof of concept, the experiments employed two FC-like sources with different I–V characteristics. The experimental results indicated that the power assignment under the rated condition had a relative error of < 6.62%. The distribution ratio error under the load change was < 7.43%. Therefore, the proposed method can regulate the power output (operation point) of each parallel-connected FC-like power source.

Antony Plait, Pierre Saenger, David Bouquain

Energies • 2024

In this paper, a meticulous modeling approach is proposed not only for a fuel cell stack itself but also for all auxiliary components that collectively form the fuel cell system. This comprehensive modeling approach encompasses a wide range of components, including, but not limited to, the hydrogen recirculation pump and the air compressor. Each component is thoroughly analyzed and modeled based on the detailed specifications provided by suppliers. This involves considering factors such as efficiency, operating parameters, response times, and interactions with other system elements. By integrating these detailed models, a holistic understanding of the entire fuel cell system’s performance can be attained. Such an approach enables engineers and designers to simulate various operating scenarios, predict system behavior under different conditions, and optimize the system design for maximum efficiency and reliability. Moreover, it allows for informed decision-making throughout the system’s development, deployment, and operational phases, ultimately leading to more robust and effective energy systems. The model validation is performed by comparing experimental data to theoretical results, and the observed difference does not exceed 3%.

Ioannis Ieropoulos, Iwona Gajda, Jiseon You et al.

ECS Meeting Abstracts • 2016

Microbial fuel cells (MFCs) convert organic waste directly into electricity, which is a competitive advantage over other energy generating systems. It is a technology that offers an environmentally friendly service at high-energy conversion efficiency. Full commercialization has yet to be achieved in areas such as wastewater treatment and remote power applications, due to challenges with the level of power output from individual units, cost of materials and scale-up. Unlike some conventional chemical fuel cells that are now fully commercial, MFCs are still at pilot scale testing [1-4]. However, several smaller-scale MFC-based applications have been implemented including, biochemical oxygen demand (BOD) measuring sensors (HABS2000, KORBI), benthic MFCs as on-site power sources for conventional sensors [5-7] and power sources for small electronic gadgets, mobile phones and robots, as well as Pee Power urinals [3, 8, 9]. Single MFCs can generate on average <0.5V at maximum power transfer, which is lower than what electronic circuits and peripheral devices require. Scaling up is therefore critical for the technology to be implemented in practice and find a route to market, and for this purpose several approaches have been proposed. One approach is to enlarge individual units to scale [2], and the second is to miniaturise individual units [10] and stack collectives of these small units together [11, 12]. Independent of size or volume, more than one unit will need to be connected together to increase the voltage and current up to operational levels. This can be in series (voltage boost), parallel (current boost) or a combination of series and parallel (voltage + current boost). As an alternative to these common connections, a novel method of MFC configuration is suggested in this work, with the introduction of added electrodes – so-called “pins”. The purpose of this type of connection is to enable control and monitoring of the MFC by modulating the physicochemical environment and the idea is derived from electronic transistors and control theory. This long-term study has been focusing on the development of MFCs for practical applications and scale-up. Through this approach, a novel transistor analogy is proposed with potential for improving power, controlling biochemical reactions, sensing and unconventional computation. Acknowledgements This work has been supported by the UK EPSRC, grant numbers EP/I004653/1 and EP/L002132/1 and Bill & Melinda Gates Foundation, grant no. OPP1094890. References [1] Osman, M. H., Shah, A. A. and Walsh F. C. Recent progress and continuing challenges in bio-fuel cells. Part II: Microbial. Biosens Bioelectr 2010;26:953–63. [2] Logan, B. E. Appl Microbiol Biotechnol. 2010;85:1665–71. [3] Reinvent the Toilet Fair: India, 2014. http://www.impatientoptimists.org/Posts/2014/03/Reinvent-the-Toilet-Fair-India--Progress-Innovation-Excitement#.VmuEY9DWvrc (visited 11 December 2015). [4] University of the West of England. “Pee-power” to light camps in disaster zones 2015. [5] Du, Z., Li, H. and Gu. A state of the art review on microbial fuel cells: A promising technology for wastewater treatment and bioenergy. Biotechnol Adv. 2007;25:464-72. [6] Reimers, C. E., Girguis, P., Stecher, H. A., Tender, L. M., Ryckelynck, N. and Whaling, P.Microbial Fuel Energy from an Ocean Cold Seep. Geobiol. 2006;4:123-36. [7] Beyenal, H. and Babauta, J. (2015) Large-Scale Benthic Microbial Fuel Cell Construction, Deployment, and Operation, in Biofilms in Bioelectrochemical Systems: From Laboratory Practice to Data Interpretation, John Wiley & Sons, Inc, Hoboken, NJ, USA. doi: 10.1002/9781119097426.ch11 [8] Ieropoulos, I., Greenman, J., Melhuish, C. and Horsfield, I. (2010) EcoBot-III – A Robot with Guts. Proceedings of ALife XII, MIT Press, 733-40. [9] Ieropoulos, I. A., Ledezma, P., Stinchcombe, A., Papaharalabos, G., Melhuish, C. and Greenman, J. Waste to real energy: the first MFC powered mobile phone. PCCP. 2013;15:15312-16. [10] Ringeisen, B., Henderson, E., Wu, P. K., Pietron, J., Ray, R., Little, B., Biffinger, J. C. and Jones-Meehan, J. M. High Power Density from a Miniature Microbial Fuel Cell Using Shewanella oneidensis DSP10. Env Sci Technol. 2006;40:2629-34. [11] Cohen, B. The Bacterial Culture as an Electrical Half-Cell. J. Bacteriol. 1931. [12] Ieropoulos I, Greenman J, Melhuish C. Microbial fuel cells based on carbon veil electrodes: Stack configuration and scalability. Int J Energy Res 2008;32:1228–40.

Charles A. Waggoner, Michael S. Parsons, Paxton K. Giffin

Volume 1: Low/Intermediate-Level Radioactive Waste Management; Spent Fuel, Fissile Material, Transuranic and High-Level Radioactive Waste Management • 2013

Processing liquid wastes frequently generates off gas streams with high humidity and liquid aerosols. Droplet laden air streams can be produced from tank mixing or sparging and processes such as reforming or evaporative volume reduction. Unfortunately these wet air streams represent a genuine threat to HEPA filters. High efficiency mist eliminators (HEME) are one option for removal of liquid aerosols with high dissolved or suspended solids content. HEMEs have been used extensively in industrial applications, however they have not seen widespread use in the nuclear industry. Filtering efficiency data along with loading curves are not readily available for these units and data that exist are not easily translated to operational parameters in liquid waste treatment plants. A specialized test stand has been developed to evaluate the performance of HEME elements under use conditions of a US DOE facility. HEME elements were tested at three volumetric flow rates using aerosols produced from an iron-rich waste surrogate. The challenge aerosol included submicron particles produced from Laskin nozzles and super micron particles produced from a hollow cone spray nozzle. Test conditions included ambient temperature and relative humidities greater than 95%. Data collected during testing HEME elements from three different manufacturers included volumetric flow rate, differential temperature across the filter housing, downstream relative humidity, and differential pressure (dP) across the filter element. Filter challenge was discontinued at three intermediate dPs and the filter to allow determining filter efficiency using dioctyl phthalate and then with dry surrogate aerosols. Filtering efficiencies of the clean HEME, the clean HEME loaded with water, and the HEME at maximum dP were also collected using the two test aerosols. Results of the testing included differential pressure vs. time loading curves for the nine elements tested along with the mass of moisture and solid material on each element at final dP. Plots of overall filtering efficiencies for DOP (spherical aerosol) and dry surrogate (aspherical aerosols) at specified dPs were computed for each filter. Filtering efficiencies were determined as a function of particle size. Curves were also generated showing the most penetrating particle size as a function of dP. A preliminary set of tests was conducted to evaluate spray location, duration, pressure, and wash volume for in-place cleaning the interior surface (reducing dP) of the HEME element. A variety of nozzle designs were evaluated and test results demonstrated the potential to overload the HEME (saturate filter medium) resulting in very high dPs and extensive drain times. At least one combination of spray nozzle design, spray location on the surface of the element, and spray time/pressure was successful in achieving extension of operational life.

Youngil Song, Junyeong An, Kyu‐Jung Chae

Energy Technology • 2017

Abstract The anode of a microbial fuel cell (MFC) was inoculated using recycling activated sludge and incubated at 25 °C (start‐up temperature, denoted as 25 °C stu ) for 2 weeks, and the temperature was then stepwise changed to 35, 25, 45, and 25 °C. A maximum power density of 54 mW m −2 and a current density of 348 mA m −2 were observed at 25 °C stu . The MFC performances at 35 and 45 °C were much lower compared to 25 °C stu due to substrate limitations. After operation at 35 (11 days) and 45 °C (9 days), the temperature was switched back to the initial temperature of 25 °C, but the MFC performance did not recover to the initial level for 25 °C stu . These results confirm that after MFC stabilization at a start‐up temperature, the increase of MFC operating temperature could lead to a failure of the MFC system, indicating that the operating temperature of an MFC system for wastewater treatment should be stable and remain as identical to its start‐up temperature as possible.

Carlo Santoro, Francesca Soavi, Alexey Serov et al.

ECS Meeting Abstracts • 2016

A self-powered supercapacitive microbial fuel cell (MFC) is here reported. Microbial fuel cell (MFC) is an interesting bio-electrochemical technology that is used for wastewater treatment with simultaneous organic removal and electricity generation. Due to the much lower current/power production compared to hydrogen and methanol fuel cells, a smart design is desired to increase performance up to the levels required for real applications. The most used method to store/deliver energy from an MFC at high rate is coupling it with an external supercapacitor with capacitances in the order of Farads 1 . The main disadvantage of this approach is that high capacitance supercapacitors require long time to be recharged at the low MFC current regimes. This makes the MFC-Supercapacitor system working with long recharge stand-by time and low switch-on/off frequency. Here, a microbial fuel cell has been integrated with internal supercapacitor (SC) 2 . The MFC anode was the SC negative electrode. Its potential (≈-0.5 V vs Ag/AgCl) was related to the presence of bacteria that consumed the oxygen present into the solution and colonize the carbon brush electrode. The MFC cathode, an air-breathing cathode working at ≈+0.1 V vs Ag/AgCl, was the SC positive electrode. Single chamber MFC filled with 50% volume of 0.1M phosphate buffer saline (PBS) solution and 50% activated sludge was used during the experiments. Galvanostatic discharges were performed with current pulses up to 4 mA. An MFC with activated carbon (AC)-based cathode featured a maximum power of 2.98 Wm -2 (5.36 Wm -3 ) which was mainly affected by the cathode ohmic losses. In order to further enhance the output, two strategies were adopted. The first one was simply enhance the overall cell voltage by utilizing cathode catalysts with higher potential like non-platinum based catalyst (iron-aminoantipyrine (Fe-AAPyr)) 3 or enzymatic-based catalyst (bilirubin oxidase (BOx) 4 ). The second option was to utilize an additional high capacitive electrode of low resistance, short-circuited with the cathode, coupled with the negative electrode (MFC-AdE). The AdE used was a carbon brush coated with AC. The first option brought to the increase of the voltage from 0.6V with AC to 0.68V with Fe-AAPyr and to 0.78V with BOx cathode. Figure 1 showed the discharge of the MFC using Fe-AAPyr cathode with and without the AdE. Consequently, maximum power (P max ) achieved 6.53 Wm -2 (11.76 Wm -3 ) and 4 Wm -2 (7.2 Wm -3 ) using BOx and Fe-AAPyr, respectively. The use of AdE significantly reduced the cell ohmic drop and led to a much important improvement (Figure 1). Pulses discharges up to 45 mA were performed. The cell resistance decreased by one order of magnitude allowing higher current pulses and power generated. In fact, P max was 84.4 Wm -2 (152 Wm -3 ) with BOx cathode, 62.2 Wm -2 (112 Wm -3 ) with Fe-AAPyr and 26.7 Wm -2 (49 Wm -3 ) with AC cathode. The addition of the AdE is a smart and easy way to overcome the ohmic losses of the system. This current/power output is in the same range of MFCs coupled with external supercapacitors. The main advantage of the system here reported is the much shorter recharging time (in the order of seconds/minutes) of interest for applications that have to be powered with more frequent pulses, like sensors. Also, utilization of the MFC electrodes as the supercapacitor electrodes makes the system simpler and more compact. Acknowledments CS was funded by the Electrochemical Society and Bill & Melinda Gates Foundation under initiative: “Applying Electrochemistry to Complex Global Challenges”. FS acknowledges financial support by Università di Bologna (Researcher Mobility Program). References 1. G. Papaharalabos, J. Greenman, C. Melhuish, C. Santoro, P. Cristiani, B. Li, I. Ieropoulos. Int. J. Hydrogen Energy 38(26) , 11552 (2013). 2. C. Santoro, F. Soavi, A. Serov, C. Arbizzani, P. Atanassov. Biosens. Bioelectron. 78 , 229 (2016). 3. C. Santoro, A. Serov, C.W. Narvaez Villarrubia, S. Stariha, S. Babanova, K. Artyushkova, A.J. Schuler, P. Atanassov. Sci. Rep. 5 , 16596 (2015). 4. C. Santoro, S. Babanova, P. Atanassov, B. Li, I. Ieropoulos, P. Cristiani. J. Electrochem. Soc. 160 (10) , H720 (2013). Figure 1. Cell voltage and electrode potentials of the MFC and MFC-AdE at 1mA discharge pulse. The cathode was Fe-AAPyr. Figure 1

Chloe Gordon, Katey M Sheets, Jason J. Keleher

ECS Meeting Abstracts • 2024

Microbial fuel cells (MFCs) have emerged as renewable energy sources due to their intrinsic properties to directly convert organic substrates into electrical energy. However, sub-optimal power density, limited long-term stability, and high operational costs have stunted integration at the industrial scale. These systems function through the exploitation of catalytic events of microbes under anaerobic conditions. The bacterial interactions at the electrode interface and associated electron transfer mechanisms directly impact fuel cell performance. The prominent issue is the formation of non-productive biofilms at the anode. This work focuses on the strategic design of a conductive polysaccharide-based (i.e., cellulose, agar, alginate, pectin) nanocomposite material to increase productive interactions at the anode-microbe interface. Results have shown that upon exposure to E. coli , the conducting polymer nanocomposite demonstrates enhanced current flow. Furthermore, the electrode surface was modified via non-covalent linkages of organic fuels, such as glucose, with TiO 2 nanoparticles to decrease bacteria-substrate repulsions. The sugar-functionalized nanoparticle electrodes also exhibited an increased electrical response with enhanced photochemical activity. This phenomenon was observed through decreased fluorescence intensity without a decrease in cell viability and open circuit potential in the presence of light. Lastly, the “blurred” disciplinary boundaries were exploited as a model for developing an active Course-based Undergraduate Research Experience (CURE). This experience emphasized the importance of interdisciplinary problem-solving, experimental design, and the development of essential critical thinking skills.

Denys Derevianko, Volodymyr Vorobel

POWER ENGINEERING: economics, technique, ecology • 2023

In this paper, an analysis of the potential of using RES for the heat supply needs of public and residential buildings in Ukraine and the world is carried out. It was determined that Ukraine has one of the largest potentials in Europe for the use of RES. An analysis of the "Energy Strategy of Ukraine for the period until 2035 "Security, energy efficiency, competitiveness" was carried out and it was concluded that there is a trend towards decentralization of energy supply and an increase in the use of RES technologies for thermal energy generation. The total primary energy supply was analyzed by types of sources and volumes of generation. On the basis of a comparative analysis of actual and projected data on RES energy generation, it was concluded that there is a trend towards a gradual decrease in thermal energy generation by coal, gas, and oil-fired boilers, and an increase in generation using biomass boilers, solar collectors, and heat pumps. Based on the analysis of the Net Zero strategy, it was concluded that Ukraine and the world will gradually reduce the use of traditional generation and introduce modern technologies not only for the needs of electricity supply, but also for the needs of heat supply.

Charalampos Patsios, M. Antonakopoulos, Antonios Kladas

Materials Science Forum • 2014

This paper proposes a control methodology for the reliable integration of a proton exchange membrane fuel cell (PEMFC) into a hybrid generation system for stand-alone power applications. The system employs a wind generator (WG) and photovoltaic (PV) arrays as main energy sources while the fuel cell (FC) is included for supplying excess power demand. An ultra-capacitor (UC) bank is also implemented in order to cover rapid changes of both load demand and power supply due to changes in wind speed or solar radiation. The system operation is based not only on the supply-demand equilibrium but also includes concerns of FC long-term durability as well as actual constraints regarding electrolyzer operation and considerations of energy efficiency. The system performance is evaluated on a 24-hour operating time period basis under highly-varying load conditions. A particular control technique is proposed for power flow regulation ensuring FC life extension, system efficiency optimization and uninterrupted supply of demand.

Mahendiravarman Elangovan, Sangeetha Dharmalingam

Environmental Progress & Sustainable Energy • 2015

A sustainable clean energy production from oxidation of biodegradable materials was carried out in a microbial fuel cell (MFC) stack consisting of four MFC units. The stack was fabricated and tested for its scalability using a high engineering, low oxygen mass transfer membrane; namely, sulfonated poly ether ether ketone. Sodium acetate was used as the substrate and dairy waste inoculum was utilized as biocatalyst for power generation. Maximum current and power density generation produced in the MFC stack were 1033 mA m −2 and 826 mW m −2 , respectively, with a columbic efficiency of 58%. Impedance spectroscopy demonstrated the internal resistance distribution in a single unit cell of the MFC stack and indicated a much lower resistance of 8.5 Ω. Cyclic voltammetry revealed that the enrichment of culture and partial anodic biofilm mixture increased the electrochemical activity. Additionally, experiments were performed with dairy wastewater which produced a moderate current and power density of 672 mA m −2 and 640 mW m −2 , respectively. The MFC stack system demonstrated the ability to treat real wastewater with the added benefit of harvesting electricity energy. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 80–87, 2016

Carlo Mapelli, Valeria Mapelli, Lisbeth Olsson et al.

Advanced Engineering Materials • 2012

Abstract Nowadays, the development of new green technologies has been promoted worldwide both by public and private institutions. In this context the research on microbial fuel cells (MFC) represents a promising alternative to carbon based energy sources. Unfortunately, this technology has been always affected by too low current density output for allowing an intensive application in the industrial and civil field. The study deals with this limitation and focuses on the implementation of metallic sponges, specifically cast iron based, as electrodes, aiming at increasing the exposed surface and thus the current density at the MFC anode. Cast iron was selected because of its low toxicity for the microorganisms, however its high melting point carries several problems for the manufacture process. Parallel to this, the realization of electrodes using foamed metals implies further issues related to the generation of correct pore size distribution and adequate bacterial activity. For instance, the metal foams are expected to be open‐cell type, so that there can be an efficient mass transport also to the inner regions of the electrode. In order to control these parameters the metal sponges are produced by infiltration of cast iron on ceramic beds. Combining previous data with the measurements of power generation efficiency the authors conclude the study attempting to design MFCs with metal foamed electrodes.

S. K. Mazumder, R. Burra, K. Acharya et al.

1st International Fuel Cell Science, Engineering and Technology Conference • 2002

SOFC stacks respond quickly to changes in load and exhibit high part- and full-load efficiencies (due to rapid electrochemistry), which is not true for the balance of plant (BOP), where load-following time constants are several orders of magnitude higher. This dichotomy diminishes the reliability and performance of the electrode with increasing demand of load. Because these unwanted phenomena are not well understood, the manufacturers of SOFC use conservative schemes to control stack responses to load variations, which limit the applicability of SOFC systems from a cost standpoint. Thus, a need exists for the synthesis of component- and system-level models of SOFC power-conditioning systems and the development of methodologies for investigating the system-interaction issues (which reduce the lifetime and efficiency of a SOFC) and optimizing the responses of each subsystem. Equally important are “multiresolution” finite-element modeling and simulation studies that can predict the impact of changes in system-level variables (e.g., current ripple and load-transients) on the local current densities, voltages, and temperature (these parameters are very difficult or cumbersome, if not impossible to obtain) within a SOFC cell. Towards that end, this paper presents a design methodology (with illustrations) for a simulation tool that will enable comprehensive analyses of above (critical) issues.

R. K. Gautam, K. K. Kar

Fuel Cells • 2016

Abstract The most essential and costly component of polymer electrolyte membrane fuel cells is the bipolar plate. The production of suitable composite bipolar plates for polymer electrolyte membrane fuel cell with good mechanical properties and high electrical conductivity is scientifically and technically very challenging. This paper reports the development of composite bipolar plates using exfoliated graphite, carbon black, and graphite powder in resole‐typed phenol formaldehyde. The exfoliated graphite with maximum exfoliated volume of 570 ± 10 mL g −1 used in this study was prepared by microwave irradiation of chemically intercalated natural flake graphite in a few minutes. The composite plates were prepared by varying exfoliated graphite content from 10 to 35 wt.% in phenolic resin along with fixed weight percentage of carbon black (5 wt.%) and graphite powder (3 wt.%) by compression molding. The composite plates with filler weight percentage of 35/5/3/exfoliated graphite/carbon black/graphite powder offer in‐plane and trough‐plane electrical conductivities of 374.42 and 97.32 S cm −1 , bulk density 1.58 g cm −3 , compressive strength 70.43 MPa, flexural strength 61.82 MPa, storage modulus 10.25 GPa, microhardness 73.23 HV and water absorption 0.22%. Further, I–V characteristics notify that exfoliated graphite/carbon black/graphite powder/resin composite bipolar plates in unit fuel cell shows better cell performance compared exfoliated graphite/resin composite bipolar plates. The composite plates own desired mechanical properties with low bulk density, high electrical conductivity, and good thermal stability as per the U.S. department of energy targets at low filler concentration and can be used as bipolar plates for proton exchange membrane fuel cells.

Washington Logroño, Alex Guambo, Mario Pérez et al.

Sensors • 2016

Microbial fuel cells represent an innovative technology which allow simultaneous waste treatment, electricity production, and environmental monitoring. This study provides a preliminary investigation of the use of terrestrial Single chamber Microbial Fuel Cells (SMFCs) as biosensors. Three cells were created using Andean soil, each one for monitoring a BOD concentration of synthetic washed rice wastewater (SRWW) of 10, 100, and 200 mg/L for SMFC1, SMFC2 and SMFC3, respectively. The results showed transient, exponential, and steady stages in the SMFCs. The maximum open circuit voltage (OCV) peaks were reached during the elapsed time of the transient stages, according to the tested BOD concentrations. A good linearity between OCV and time was observed in the increasing stage. The average OCV in this stage increased independently of the tested concentrations. SMFC1 required less time than SMFC2 to reach the steady stage, suggesting the BOD concentration is an influencing factor in SMFCs, and SMFC3 did not reach it. The OCV ratios were between 40.6–58.8 mV and 18.2–32.9 mV for SMFC1 and SMFC2. The reproducibility of the SMFCs was observed in four and three cycles for SMFC1 and SMFC2, respectively. The presented SMFCs had a good response and reproducibility as biosensor devices, and could be an alternative for environmental monitoring.

Bradley G. Lusk, Alexandra Colin, Prathap Parameswaran et al.

Microbial Biotechnology • 2017

Summary An enriched mixed culture of thermophilic (60°C) bacteria was assembled for the purpose of using cellulose to produce current in thermophilic microbial electrolysis cells ( MEC s). Cellulose was fermented into sugars and acids before being consumed by anode‐respiring bacteria ( ARB ) for current production. Current densities ( j ) were sustained at 6.5 ± 0.2 A m −2 in duplicate reactors with a coulombic efficiency ( CE ) of 84 ± 0.3%, a coulombic recovery ( CR ) of 54 ± 11% and without production of CH 4 . Low‐scan rate cyclic voltammetry ( LSCV ) revealed a mid‐point potential ( E ka ) of −0.17 V versus SHE . Pyrosequencing analysis of the V4 hypervariable region of 16S rDNA and scanning electron microscopy present an enriched thermophilic microbial community consisting mainly of the phylum Firmicutes with the Thermoanaerobacter (46 ± 13%) and Thermincola (28 ± 14%) genera occupying the biofilm anode in high relative abundance and Tepidmicrobium (38 ± 6%) and Moorella (11 ± 8%) genera present in high relative abundance in the bulk medium. The Thermoanaerobacter (15 ± 16%) and Brevibacillus (21 ± 30%) genera were also present in the bulk medium; however, their relative abundance varied by reactor. This study indicates that thermophilic consortia can obtain high CE and CR , while sustaining high current densities from cellulose in MEC s.

Michael Beachy, Paul Matter, Christopher Holt

ECS Meeting Abstracts • 2017

Introduction Portable Non-Destructive Inspection (NDI) equipment, such as Eddy Current (EC) and Ultrasonic Testing (UT), provide important tools for the Air Force to characterize flaws, cracks, and/or defects in aircraft, thus monitoring potential safety issues. Most NDI equipment is powered by a battery (alkaline, NiCad, NiMH, or Li-ion) that typically comprises a large percentage of the size and weight of the equipment. The Air Force is interested in finding alternative forms of energy for NDI equipment, due to issues with existing battery technologies that include logistical challenges, battery reliability/degradation, limited portability, and safety. Direct Ethanol Fuel Cell (DEFC) systems could potentially provide a significant advantage over conventional battery technologies, including nearly instantaneous recharging, lighter weight, longer operational times, higher power, and improved cycle life. Further, the 25-Watt power requirements of the NDI equipment are similar to a number of other portable electronics that could benefit from the technology. Materials and Methods Single cell direct ethanol fuel cells were prepared using both commercially available anion exchange membranes and experimental reduced crossover membranes. The cell anode was prepared by depositing a hydrothermally synthesized Pd-based catalyst onto a conductive carbon backing. The cell cathode consisted of pH Matter’s non-metal based oxygen reduction reaction catalyst (COR). The COR catalyst was treated with a PTFE additive to reduce ethanol crossover. The catalyst was deposited onto a commercial carbon paper (Toray) and annealed in air. Testing was completed in a nickel metal set-up with PTFE seals and consisted of mechanical compression of each component to form the cell assembly. The anode was supplied with a fuel composition consisting of 5M KOH and 5M ethanol in distilled water. Air was supplied to the cathode at approximately 25 sccm/cm 2 and at ambient pressure. Cell temperature was controlled between ambient and 60°C as to prevent degradation of the cell membrane. Cyclic voltammetry curves were obtained using a PAR Versastat 3 potentiostat between OCV and 100 mV. Simulated load testing was carried out by operating the cell at a steady state current of 65 mA/cm 2 . Significance Fuel cells provide electricity through an efficient, pollution free, and quiet electrochemical process. However, the adoption of commercial fuel cell systems has been hampered by the logistics of providing a reliable, high purity, and low cost hydrogen [1]. Some fuel cell systems, such as SOFC and Direct Methanol, offer an opportunity to use more readily available fuels, such as liquid methanol or methane. However, these systems have been unable to achieve wide-scale commercialization due to technological challenges, such as stability and lifecycle performance.[2-3] Furthermore, methanol is considered toxic and poses environmental disposal challenges [4]. In contrast, ethanol is readily available in most markets, is liquid at room temperature, has very low toxicity, and can be readily disposed upon dilution with water. Furthermore, logistics of alcohol transport are minimal, a critical requirement for adoption in the Air Force application. In this effort, direct ethanol fuel cells were demonstrated to achieve transient power densities of 80 mW/cm 2 at an operational temperature of 60°C and steady state power in excess of 20 mW/cm 2 , the target power required for use in NDI equipment, for greater than 20 hours. Furthermore, the replacement of fuel allowed for performance recovery of the fuel cell and continued operation in excess of 100 hours. Finally, the cells were incorporated into a full-scale stack and demonstrated under NDI operating conditions. In future work, the stack will be demonstrated with a 25-Watt prototype power system. References C. Huang, et al, Journal of Power Sources 303 (2016) 267-277 T. Skalar, et al, Journal of Thermal Analysis and Calorimetry (2017) 127:265–271 C. Xu, et al, Journal of Power Sources 168 (2007) 143–153 Y.S. Li, et al, Journal of Power Sources 187 (2009) 387–392 Figure 1

Meisam Peiravi, Jia Liu

ECS Meeting Abstracts • 2016

There are almost 46,000 abandoned mines all over the United States. These mines produce heavy-metal-rich sulfuric acid solution called acid mine drainage (AMD), which has brought long-term water and soil pollution impact, according to the US department of the interior [1]. Different technologies have been used to remediate the surface water, groundwater and soil contaminated by the AMD. These methods include physical, biological, and chemical methods which are generally chemical intensive or the treatment period is relatively long. A better approach for AMD treatment is using microbial fuel cell (MFC), a type of bioelectrochemical systems (BES). MFC uses microorganisms to convert the chemical energy in the biodegradable materials to electricity and at the same time removes the heavy metals in AMD by precipitation and enhances the pH of the drainage. Dry sludge from wastewater treatment plant was used as electron donors for the first time for AMD remediation in the MFC. This treatment technology offers a cheap and environmentally benign approach for integrated waste utilization, energy production and wastewater treatment. Using BES with different mechanisms, different heavy metals have been removed, such as nickel, copper, lead, cadmium and zinc. [2&3&4]. In this study, AMD was treated in the cathode chamber of the MFC with continuous air injection into the chamber, and dry sludge was placed in the anode chamber of the MFC. AMD samples were taken from an abandoned coal-mine in Illinois Coal Basin around Carbondale IL, and the dry sludge was from Carbondale Southeast Wastewater Treatment Plant in Carbondale, IL. The plant used activated sludge tank as secondary treatment process. The dry sludge was formed after activated sludge digestion and drying. Anion exchange membrane (Membrane International Inc) was used to separate the two chambers. Carbon fiber brush was used as the anode electrode, and platinum coated carbon sheet was used as the cathode electrode. With catalyst used, the removal speed of heavy metals can be enhanced. The volume of each chamber was 150 mL. The dry sludge in the anode chamber of the MFC was saturated with D.I. water and a mixture of bacteria from different sources was inoculated into the chamber. No external nutrients were added into the chamber as the dry sludge contains reach nutrition, including organic compounds and different salts. Air was injected into the cathode chamber filled with the AMD. A multimeter was used to record the whole cell potential with an external resistor of 1 kΩ resistance, and the potential of each half cell was also recorded by a data logger (DataLoggerInc) with an Ag/AgCl reference electrode placed in the cathode chamber. The results showed that the closed circuit voltage of the whole cell was kept increasing during the 5 days of operation with the maximum reached voltage of 0.1 V. With the density peak method, the internal resistance of the MFC was measured to be 650 Ω. The pH and the ORP of the AMD changed from 2.57 and 619.9 mV to 4.49 and 263.2 mV respectively after 5 days. White-gray colored precipitation was observed to be formed on the bottom of the cathode chamber. The color of the AMD was changed from yellow-brown before the test to transparent after 5 days. Scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) was used to test the composition of the precipitate and to observe its morphology. The EDS test showed the existence of Al, Cu, and Fe in the precipitation. Precipitates with different sizes were formed with the maximum less than 5 µm. The preliminary results from this study indicated the possible treatment pathway of AMD by MFC with electricity generation during the treatment process and by using dry sludge from the wastewater treatment plant; no additional chemicals are needed for the treatment process. References [1]. US department of the interior, bureau of land managment. 2014. Abandoned Mine Lands. http://www.blm.gov/wo/st/en/prog/more/Abandoned_Mine_Lands.html [2]. Wang, H., Ren, Z.J., 2013. A comprehensive review of microbial electrochemical systems as a platform technology. Biotechnology advances. Volume 31, issue 8, pages 1796-1807. [3]. Logan, B.E., Rabaey, K., 2012. Conversion of wastes into bioelectricity and chemicals by using microbial electrochemical technologies. Science 337 (6095), 686-690. [4]. Wang, H., Ren, Z.H., 2014. Bioelectrochemical metal recovery from waste water: A review. Water research, (66 ) 219-232.

Adegunloye D. V, Olotu T. M

European Scientific Journal, ESJ • 2017

Generating electricity using microbial fuel cell powered by benthic mud collected from two locations in Akure was carried out. The locations were Riverbed of FUTA and Apatapiti area of Akure. This was achieved by building anode and cathode containers connected together by a salt bridge and an external circuit was made to transfer the electrons from the anode to the cathode. Bacteria and fungi were isolated from the benthic mud for eight days using standard microbiological techniques. Lactobacillus plantarum, Escherichia coli, Bacillus subtilis, Enterobacter aerogenes, Trichoderma sp, Mucor sp and Alterania sp; Lactobacillus plantarum, Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Myrothecium sp and Geotrichum candidum were bacteria and fungi isolated from the benthic mud of Apatapiti area and Riverbed of Futa, Akure respectively. This was used for the generation of electricity using unsterilized mud sample and the control setup was sterilized mud from same source. The set-up was monitored every 24hrous to determine the voltage and current generated. The pH, concentration and temperature were measured. The temperature remains constant throughout the experiment. The set-up were operated at a normal temperature of 27oC and 29oC for Riverbed of FUTA and Apatapiti area of Akure respectively. The peak voltage was between 182.5V and 192.5V and current produced from the main set-up was between 0.3A to 0.53A for Futa river bed while for Apatapiti area of Akure the peak voltage and current were 192.5V and 0.3A respectively. Higher microbial population, current and voltage were observed to be generated in River bed of Futa than Apatapiti area. The difference in the voltage and current and the control set-up shows that anaerobic microorganisms are capable of producing electricity from microbial fuel cell under appropriate conditions.

Liam Doherty, Yaqian Zhao

Water Science and Technology • 2015

By integrating microbial fuel cells (MFCs) into constructed wetlands (CWs) the need and cost of building a reactor are eliminated, while CWs provide the simultaneous redox conditions required for optimum MFC performance. Two single-stage MFC-CWs, with dewatered alum sludge cake as the main wetland medium for enhanced phosphorus removal, were operated to determine the effects of electrode separation and flow regimes on power production and wastewater treatment. When the anode is buried and the cathode is at the air–water interface the system is inhibited by a large ohmic resistance resulting from the increased electrode separation. By placing the cathode directly above the anode and operating the system with simultaneous upflow into the anode and downflow into the cathode the ohmic resistance is reduced. The chemical oxygen demand (COD) removal efficiency was, however, reduced to 64% (compared with 79%). A two-stage system was subsequently run for fuller wastewater treatment and increased power production. The results indicate that a two-stage MFC-CW can increase the normalized energy recovery and improve removal efficiencies of COD, total nitrogen, NH4+, total phosphorus and reactive phosphorus to 93 ± 1.7%, 85 ± 5.2%, 90 ± 5.4%, 98 ± 5.3% and 99 ± 2.9%, respectively.

Jason Jones, Shing Chen, Tony Phan et al.

ECS Meeting Abstracts • 2016

Utilizing anode-respiring bacteria, microbial fuel cells (MFCs) are a technology that is able to remove organic materials from waste streams and generate electricity in the process. MFCs have been considered as an alternative to conventional wastewater treatment using activated sludge, due to potentially lower cost of operation (no pumping of oxygen) and the ability to directly control the removal of organics. Our study is focused on designing modular and scalable MFC reactors that can be utilized in pilot-scale installations. We tested several operational parameters and two different anode electrode configurations to study the effect on current production and chemical oxygen demand (COD) removal. The operational parameters included running the systems in MFC-mode with a constant resistance, alternating open circuit/closed circuit operation (open circuit for 30 minutes, once a day), and applying a set voltage to the circuit. The different anode electrode configurations included graphite-coated stainless steel bolts or carbon fiber brushes. All of the reactors utilized the same gas diffusion oxygen reducing cathode design. Samples were taken daily to evaluate the COD removal rates, monitor/control pH, and determine the concentration of dissolved oxygen in the reactors. Current production was monitored in real-time and polarization measurements were executed periodically for the electrodes to evaluate the activities of the associated microbial communities at the anodes, as well as the efficiency of cathode operation. Reactors under alternating open circuit/closed circuit operation demonstrated improved performance longevity than those held under constant resistance (MFC-mode). This may be a result of decreased biofouling on the cathode per our previous work [1] or improving the charge storage capacity of the anode biofilms [2] . Our preliminary results showed that lowering the applied resistance to 22Ω yielded current production up to ~15 mA and COD removal rates of 55 mg/L/day, as compared to a resistance of 560Ω, which yielded ~1mA and 21 mg/L/day, respectively. In regards to anode material performance, our studies showed that carbon fiber brushes allowed for COD removal rates over 10 times higher than the coated stainless steel bolts, and up to an additional ~8mA of current production. Future work will include an analysis of COD removal and current production normalized by electrode surface area and electrode-associated biomass to better compare results and elucidate the system parameters that are highly correlated to improved MFC performance. Figure 1

Aisha Umar, Islem Abid, Mohammed Antar et al.

Microbial Cell Factories • 2023

Abstract Color chemicals contaminate pure water constantly discharged from different points and non-point sources. Physical and chemical techniques have certain limitations and complexities for bioenergy production, which motivated the search for a novel sustainable production approaches during dye wastewater treatment. The emerging environmental problem of dye decolorization has attracted scientist's attention to a new, cheap, and economical way to treat dye wastewater and power production via fungal fuel cells. Ganoderma gibbosum was fitted in the cathodic region with laccase secretion in the fuel cell. At the same time, dye water was placed in the anodic region to move electrons and produce power. This study treated wastewater using the oxidoreductase enzymes released extracellularly from Ganoderma gibbosum for dye Remazol Brilliant Blue R (RBBR) degradation via fungal-based fuel cell. The maximum power density of 14.18 mW/m 2 and the maximum current density of 35 mA/m 2 were shown by the concentration of 5 ppm during maximum laccase activity and decolorization of RBBR. The laccase catalysts have gained considerable attention because of eco-friendly and alternative easy handling approaches to chemical methods. Fungal Fuel Cells (FFCs) are efficiently used in dye treatment and electricity production. This article also highlighted the construction of fungal catalytic cells and the enzymatic performance of fungal species in energy production during dye water treatment.

Monica Mejía-López, Orlando Lastres, José Luis Alemán-Ramírez et al.

Catalysts • 2024

Sediment microbial fuel cells (SMFC) are bioelectrochemical systems that can use different wastes for energy production. This work studied the implementation of nanoparticles (NPs) of α-FeOOH (goethite, which is well-known as a photoactive catalyst) in the electrodes of an SMFC for its potential use for dye removal. The results obtained demonstrate the feasibility of the NPs activation with the electrical potential generated in the electrodes in the SMFC instead of the activation with light. The NPs of α-FeOOH were synthesized using a hydrothermal process, and the feasibility of a conductive bio-composite (biofilm and NPs) formation was proven by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and electrochemical techniques. The improvement of the power density in the cell was more than twelve times higher with the application of the bio-composite, and it is attributed mostly to the presence of NPs. The results also demonstrate the NPs effect on the increase of the electron transfer, which resulted in 99% of the COD removal. The total electrical energy produced in 30 days in the SMFC was 1.2 kWh based on 1 m2 of the geometric area of the anode. The results confirm that NPs of α-FeOOH can be used to improve organic matter removal. Moreover, the energy produced due to its activation through the potential generated between the electrodes suggests the feasibility of its implementation for dye removal.

Njud S. Alharbi

Mathematical Problems in Engineering • 2012

This paper investigated microbial denitrification using electrochemical sources to replace organic matter as reductant. The work also involved developing a system that could be optimised for nitrate removal in applied situations such as water processing in fish farming or drinking water, where high nitrate levels represent a potential health problem. Consequently, the study examined a range of developments for the removal of nitrate from water based on the development of electrochemical biotransformation systems for nitrate removal. This also offers considerable scope for the potential application of these systems in broader bionanotechnology based processes. Furthermore, the work discussed the context of improved microbial fuel cell (MFC) performance, potential analytic applications, and further innovations using a bionanotechnology approach to analyse cell-electrode interactions. High nitrate removal rate of more than 95% was successfully achieved by using a MFC system modified with carbon nanomaterials.

Tingting Yang, Kexun Li

ECS Meeting Abstracts • 2016

For the first time, the hollow-spherical Co/N-C nanoparticles doped in activated carbon was used in air-cathode microbial fuel cells (MFCs). Hereof, the Co/N-C nanoparticles, which combines the advantageous features of high surface area, sufficient active sites and high degree of graphitization, had been synthesized via a simple hydrothermal reaction followed by heat treatment. As a result, the Co/N-C showed superior catalytic activity, lower internal resistance, excellent kinetic activity towards oxygen reduction reaction (ORR) in MFCs. The maximum power density of MFCs with 10%Co/N-C air cathode was as high as 2514 ± 59 mW m 2 , almost 174% higher than the control. Therefore, it can be expected that the as-synthesized Co/N-C, with extraordinary electro-catalytic performance towards ORR comparable to commercial Pt/C, will be a promising alternative to the state-of-the-art non-precious metal ORR electro-catalysts for electrochemical energy applications.

Andrea Pietrelli, Andrea Micangeli, Vincenzo Ferrara et al.

Sustainability • 2014

This work aims at investigating the possibility of a wireless sensor network powered by an energy harvesting technology, such as a microbial fuel cell (MFC). An MFC is a bioreactor that transforms energy stored in chemical bonds of organic compounds into electrical energy. This process takes place through catalytic reactions of microorganisms under anaerobic conditions. An anode chamber together with a cathode chamber composes a conventional MFC reactor. The protons generated in the anode chamber are then transferred into the cathode chamber through a proton exchange membrane (PEM). A possible option is to use the soil itself as the membrane. In this case, we are referring to, more properly, a terrestrial microbial fuel cell (TMFC). This research examines the sustainability of a wireless sensor network powered by TMFC for land monitoring and precision agriculture. Acting on several factors, such as pH, temperature, humidity and type of soil used, we obtained minimum performance requirements in terms of the output power of the TMFC. In order to identify some of the different network node configurations and to compare the resulting performance, we investigated the energy consumption of the core components of a node, e.g., the transceiver and microcontroller, looking for the best performance.

Leipengyun Deng, Mohd Amran Mohd Radzi, Suhaidi Bin Shafie et al.

International Journal of Renewable Energy Development • 2025

Fuel cell hybrid electric vehicles (FCHEVs), integrating fuel cell (FC) with batteries, have attracted significant research attention due to their emission-free operation, enhanced efficiency, and quick refuelling capabilities. Efficient energy management strategies (EMSs) are crucial in allocating energy between these sources and controlling power flow from FCs and batteries. The power following control (PFC) strategy has emerged as one of the most extensively utilized approaches in automotive applications owing to its superior real-time performance, ease of calculation, and straightforward design. This paper proposes a PFC-optimized strategy focused on improving FC durability and fuel economy by optimizing the switching control to fill the gap in frequent toggling of FC caused by traditional PFC strategy. The outcomes derived from the co-simulation conducted with AVL CRUISE and MATLAB/Simulink for developing complete FCHEV model and EMS model, respectively, indicate that under the China Light-duty Vehicle Test Cycle for Passenger Car (CLTC-P), the PFC-optimized strategy, in comparison to the traditional PFC strategy, reduces battery state of charge (SOC) fluctuations by 68.93% and decreases hydrogen consumption per 100 km by 2.71%. Meanwhile, this strategy is also proven effective in other operating conditions and reduces fuel cell switching times during operation. Therefore, the PFC-optimized strategy suggested in this study contributes to better performance in battery SOC, battery life, FC durability and fuel economy.

F. Wang, F. X. Miao, W. B. Guan

Fuel Cells • 2015

Abstract The performance of anode support of Ni‐YSZ reduced from room temperature ( T R ) to working temperature ( T w ) and at T w in anode‐supported planar solid oxide fuel cell was investigated quantitatively in situ. A 2 μm thick Pt voltage probe was embedded at the interface between the anode support and the function anode in the cell. Results showed that the power densities of the stack that was reduced from T R to T w (stack 1) and stack reduced at T w (stack 2) were 0.343 W cm −2 and 0.583 W cm −2 with the corresponding fuel utilization of 36.28% and 63.87%, respectively, under the operating voltage of 0.8 V. The degradation rate of stack 1 was 7.76 times more than that of stack 2 when the stack was discharged under a constant current of 0.476 Acm −2 for 100 h. Ni particles agglomerated in the anode support of the cell inside stack 1, whereas Ni particles in the anode support of the cell inside stack 2 were evenly distributed. The performance of stack 1 was poor mainly because of the increasing ohmic and polarization resistances caused by Ni agglomeration and decreasing porosity of the anode support.

, V.V. Bukhmirov, A.K. Sokolov et al.

Vestnik IGEU • 2023

Currently, in this country solid fuel at industrial thermal power plants, as a rule, is burned by a layer or flaring method in boilers with generation of steam which is directed to a steam turbine. This technology of generating thermal and electrical energy is characterized by relatively low efficiency and significant emissions of pollutants into the atmosphere. At the same time, the use of solid fuel in industrial energy with its preliminary gasification can significantly increase the efficiency of electricity generation and at the same time reduce the negative impact on the environment. The results of an analytical comparison of two schemes to use solid fuel in industrial energy are used as the material of the research. These two schemes are a traditional scheme and an alternative one based on its preliminary gasification. In this paper, to assess the effectiveness of the schemes under consideration, the scientific methodology of system analysis is applied. It allows us to consider any energy object as a unified system consisting of interrelated elements. The system analysis is carried out based on mathematical modeling of the technological process to obtain thermal and electrical energy. A complex balance mathematical model of an industrial thermal power plant with preliminary coal gasification is developed. The results of calculation using a mathematical model have shown that the construction of industrial combined‒cycle thermal power plants with preliminary coal gasification instead of traditional steam turbine ones will increase the key indicator of the energy efficiency of thermal power plants, coefficient of fuel utilization from 60 to 74 %. Based on the methodology of system analysis, an optimal thermal scheme of an industrial combined-cycle thermal power plant with preliminary coal gasification has been developed. Numerical values of the basic operating conditions of the thermal power plants and energy efficiency indicators have been determined using a mathematical model. The use of solid fuel at industrial thermal power plants with its preliminary gasification is a very promising direction to develop industrial energy in Russia since this method to extract the bound chemical energy of solid fuel can significantly increase the fuel utilization coefficient and the production of electrical energy and at the same time reduce emissions of contamination material into the atmosphere

Olga Tkach, Li Hong Liu, Ai Jie Wang et al.

Applied Mechanics and Materials • 2015

The aim of the study is to compare different kinds of microbial species for electricity production in the microbial fuel cells (MFCs) at low temperature. Experiments were conducted with single-chambered MFCs and medium anode inoculated with pure culture from activated sludge. Three kinds of exoelectrogens including Klebsiella sp. ALL-1, Shewanella sp. ALL-2 and Enterobacter sp. ALL-3 were used for evaluating their electricity activity. After adding solution into MFCs, the power of density grew from 50 mV to over 530 mV, and finally maintained at about 520+10 mV during the complete cycles. The results showed that MFCs with Enterobacter sp. ALL-3 had higher power and current density, shorter and more stable working circle at same level of voltage producing than other kinds of exoelectrogens. These characteristics made Enterobacter sp. ALL-3 as optimum exoelectrogen for electricity production at low temperature.

Leandro de Amorim Ratamero, Damiano da Silva Militão, Joaquim Teixeira De Assis

Caderno Pedagógico • 2023

In contemporary times, societal and legal institutions are earnestly committed to mitigating carbon dioxide (CO2) emissions into the atmosphere, thereby averting global warming. The automotive industry mirrors this commitment, necessitating the development of vehicles characterized by heightened energy efficiency. Such vehicles should boast an extended range while minimizing fuel consumption and CO2 emissions. A pivotal aspect in vehicle development involves the early determination of fuel economy (FE), contingent upon the projected characteristics of the vehicle and its intended market positioning with regard to fuel economy. Over time, diverse methodologies for calculating FE have emerged. These include hybrid regression models incorporating key input variables such as instantaneous vehicle speed and acceleration measurements, theoretical approximation methods derived from the physical properties of engine-vehicle systems, correlations among traffic-related parameters, power-demand models, as well as artificial neural networks and genetic algorithms. These approaches leverage various vehicle input data, encompassing engine speed, torque, fuel flow, intake manifold mean temperature, make of the car, engine style, weight of the car, vehicle type, transmission system type, and other relevant factors. Regrettably, the literature lacks a straightforward and expeditious means of estimating FE for a group of analogous vehicles, a deficiency addressed by the present work. The proposed empirical physical model facilitates FE estimations for a vehicle using a parsimonious set of input information: engine displacement, performance (recovery speed times), and road load data. These inputs are subjected to mathematical parameter adjustments within the empirical model. To validate the efficacy of this approach, the empirical model is applied in a Brazilian case study. The results attest to the success of the method, demonstrating a margin of error within 6% when compared to the official Brazilian government public data for the tested vehicle, particularly in the contexts of city and highway cycles.

Ansia Tiara, Safira Redzy Ramadhani, Abubakar Tuhuloula

Jurnal Bahan Alam Terbarukan • 2023

The high need of Indonesian people for electrical energy has led to an increase in energy demand. This has triggered research efforts based on renewable technologies that are efficient and environmentally friendly. One of the renewable energy sources that is widely developed is Microbial Fuel Cell (MFC). MFC works by utilizing organic matter used by microbes as an energy source in carrying out metabolic activities. This study aims to determine the effect of Bacillus subtilis and Escherichia coli bacteria with different concentrations of 10% (v/v) and 15% (v/v) on the electrical energy generated from the tofu liquid waste substrate and observe changes in pH and Biological Oxygen Demand (BOD) in the MFC system. This research method consists of several steps, namely the preparation of electrolysis equipment, electrodes, substrates, bacterial cultures, electrolytes and MFC processes. The maximum value of voltage and current in Bacillus subtilis bacteria occurred at the 10 hours with 15% (v/v) bacterial concentration which amounted to 394 mV and 10.6 mA with a bacterial population of 16.15 × 109 CFU/mL and a power density value of 126.67 × 10-4 watt/m2. Furthermore, the maximum value for Escherichia coli bacteria occurred at the 10 hours with a voltage and current of 266 mV and 5.3 mA with a bacterial population of 15.60 × 109 CFU/mL and a power density value of 55.67 × 10-4 watts/m2. The pH value of the substrate variations with the addition of Bacillus subtilis bacteria ranged from 5-6, while with the addition of Escherichia coli bacteria variations ranged from 4-5. This system also reduces the value of biological oxygen demand.

Sunil Kumar, Sulayman Jammeh, Rodrigue Samb et al.

IET Power Electronics • 2024

Abstract The general shift in vehicle propulsion systems from internal combustion engine (ICE) power‐train towards electric power‐train has led to the development of energy‐efficient and compact electric drivetrain for next‐generation automobiles such as fuel cell electric vehicles (FCEV). As opposed to ICE, fuel cell vehicles operate with higher powertrain efficiency and are combustion‐less since the only byproduct is water. In light of developmental and environmental goals, fuel cell technology is consequently seen as the evolutionary step in vehicle technology. The electric drivetrain for FCEV consists of power converters, motors, and associated control systems. Direct connection of the fuel cell stack to the DC bus and other system components is inefficient. As a result, it becomes essential to regulate the high‐voltage DC bus connecting the fuel cell stack to other system elements like the motor and energy storage devices. Therefore, DC–DC converters are designed for main power unit to provide the desired and regulated voltage to the DC bus making the system efficient and reliable. High‐voltage step‐up DC–DC converters have undergone extensive research in recent years, which has increased their functionality, performance, and efficiency for FCEV. A survey of these converters, and evaluation of their performance and index parameters, could be very helpful in designing efficient converters and for the development of vehicular electric power‐train. This paper reviews the literature on electric drive‐train, fuel cell systems, and different DC–DC converter topologies for fuel cell electric vehicles. This study aims to conduct a comprehensive assessment of the existing topologies, their applications, and comparative aspects, as well as works that haven't been covered in earlier reviews.

Carl Georg Seydel

Volume 3: Coal, Biomass and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration • 2015

In order to meet the ambitious reduction targets for future CO2 emissions and fossil fuel consumption, the extension of renewable power systems is mandatory. One main issue is the fluctuating and unpredictable availability of renewable energy. With a higher portion of renewable energy, a secure electricity supply becomes more challenging. On days with high electricity demand but low availability of renewable energy, fossil back up power plants with high flexibility and efficiency are needed. Most applicable for this requirements are combined cycle power plants, which provide both high flexibility and efficiency. On the other hand potential renewable energy is wasted during days with low electricity demand but high available renewable energy, because electricity cannot be stored yet economically in such vast amounts. In order to use the available renewable energy more efficiently, hydrogen could be produced via electrolysis during phases of surplus available renewable energy. The hydrogen serves as a high density energy storage, which can be used as an alternative fuel in combined cycle power plants for a highly efficient reconversion into electricity if necessary. In this study it is analyzed how the usage of hydrogen as the burner fuel will influence the performance of combined cycle power plants. Therefore the on- and off-design performance of a state of the art combined cycle power plant will be calculated at different ratios of hydrogen mixtures with natural gas. The thermodynamic calculations are made with the performance software GTlab of the German Aerospace Center. Furthermore the natural gas and CO2 savings for different hydrogen ratios will be quantified. The results show that the usage of hydrogen enriched fuel increases the combined cycle efficiency and power output. Accordingly a considerable reduction in CO2 emissions and fossil fuel consumption is possible.

Andika Wahyu Afrianto, Paiboon Sreearunothai, Korakot Sombatmankhong et al.

Environmental Progress & Sustainable Energy • 2024

Abstract Microbial fuel cell (MFC) is a bioelectrochemical‐based reactor that can generate electrical energy directly from wastewater by utilizing microbial activity that oxidizes the waste organic matter. This study aims to synthesize polyaniline (PANI) and deposit on a graphite carbon electrode (GCE) and activated carbon cloth (ACC) surface to use as an anode material for MFCs. The MFC performance was evaluated using oxygen and ferricyanide as electron acceptors. PANI was electropolymerized from its aniline monomer and deposited using an electrophoretic deposition method onto the electrode surface. A PANI thin film was characterized using FTIR, field emission scanning electron microscopy (FESEM), BET, and electrochemical analysis. The analysis results show the characteristic peaks of PANI at 1557 cm −1 , demonstratinjg the existence of quinoid rings (NQN), while the peaks at 1479 and 1400 cm −1 corresponding to the benzenoid (NBN) stretching in the PANI structure. The FESEM analysis confirmed that PANI appeared to have a porous structure on modified electrodes. It was found that the best system was MFC with ferricyanide as the electron acceptor. The highest power density produced is 254 mWm −2 from GCE‐PANI and 16.47 mWm −2 from ACC‐PANI. The normalized energy recovery of GCE‐PANI and ACC‐PANI in ferricyanide is 0.115 kWh kgCOD −1 and 5.67 × 10 −3 kWh kgCOD −1 , respectively. The COD removal was observed to be 88.8% for GCE‐PANI and 87.2% for ACC‐PANI from 1000 mg/L COD.

Marco Sorrentino, Giuseppe Bevilacqua, Giovanni Bove et al.

SAE Technical Paper Series • 2023

<div class="section abstract"><div class="htmlview paragraph">This work aims at addressing the challenge of reconciling the surge in road transportation with the need to reduce CO<sub>2</sub> emissions. The research particularly focuses on exploring the potential of fuel cell technology in long-distance road haulage, which is currently a major solution proposed by relevant manufacturers to get zero local emissions and an increased total payload.</div><div class="htmlview paragraph">Specifically, a methodology is applied to enable rapid and accurate identification of techno-economically effective fuel cell hybrid heavy-duty vehicle (FCH<sup>2</sup>DV) configurations. This is possible by performing model-based co-design of FCH<sup>2</sup>DV powertrain and related control strategies. Through the algorithm, it is possible to perform parametric scenario analysis to better understand the prospects of this technology in the decarbonization path of the heavy-duty transportation sector, changing in an easy way all the parameters involved. The tool used is based on the truck longitudinal dynamics model to evaluate the power required at the wheels; furthermore, the tool operates with independent control strategies that automatically adapt to the configuration under investigation. The battery and driving specifications were selected to align with the current market trends.</div><div class="htmlview paragraph">The Hybrid (FCH<sup>2</sup>DV) and plug-in (PFCH<sup>2</sup>DV) vehicle design and management scenarios were then compared, and the results indicated a fuel economy that is consistent with current literature and preliminary on-field/commercial vehicle tests. A parametric cost analysis was accomplished to determine the configuration’s techno-economic feasibility. Particularly, a literature search on the actual cost of electricity and green hydrogen destined to FCH<sup>2</sup>DV supply was carried-out, also relying on projected costs until 2030. The outcomes indicated that adopting battery charge-depleting energy management reduces PFCH<sup>2</sup>DV cost per kilometer and fuel consumption by 8 and 1.9%, respectively, as compared to the full hybrid (i.e., FCH<sup>2</sup>DV), enabling interesting cost abatement if convenient grid-based battery recharging is available.</div></div>

Sona Kazemi, Madjid Mohseni, Khalid Fatih

Energies • 2016

Passive air-breathing microbial fuel cells (MFCs) are a promising technology for energy recovery from wastewater and their performance is highly dependent on characteristics of the separator that isolates the anaerobic anode from the air-breathing cathode. The goal of the present work is to systematically study the separator characteristics and its effect on the performance of passive air-breathing flat-plate MFCs (FPMFCs). This was performed through characterization of structure, properties, and performance correlations of eight separators in Part 1 of this work. Eight commercial separators were characterized, in non-inoculated and inoculated setups, and were examined in passive air-breathing FPMFCs with different electrode spacing. The results showed a decrease in the peak power density as the oxygen and ethanol mass transfer coefficients in the separators increased, due to the increase of mixed potentials especially at smaller electrode spacing. Increasing the electrode spacing was therefore desirable for the application of diaphragms. The highest peak power density was measured using Nafion®117 with minimal electrode spacing, whereas using Nafion®117 or Celgard® with larger electrode spacing resulted in similar peak powers. Part 2 of this work focuses on numerical modelling of the FPMFCs based on mixed potential theory, implementing the experimental data from Part 1.

Prabhu N V

High Performance Polymers • 2022

The prepared mesoporous SBA-15 (Santa Barbara Amorphous-15) was sulfonated and used as filler for the preparation of sulfonated polysulfone based composite electrolyte membranes. The SBA-15 and polysulfone were sulfonated using 3-mercaptopropyl trimethoxysilane and trimethylsilyl chlorosulfonate, respectively. The different weight percentages (1, 3, and 5 wt%) of sulfonated SBA-15 (SSBA-15) were used to prepare composite electrolyte membranes. Water uptake, ion exchange capacity, swelling ratio and proton conductivity of the composite membranes were studied for assessing the suitability of the electrolyte membranes for use in fuel cells. Characterization techniques such as FT-IR, XRD, SEM, TEM and Brunauer–Emmett– Teller were used to study the physico-chemical properties of the electrolyte membranes. TEM and BET analysis showed that SBA -15 retained its mesoporous structure even after sulfonation process. The prepared membranes were then tested in an in-house built single-cell fuel cell using hydrogen as fuel and oxygen as the oxidant. The fuel cell study showed that the presence of Sulfonated SBA-15 in the polymer matrix provided additional ion exchange sites and retained water for proton transfer which resulted in higher power density of 815 mW/cm 2 with SPSU + 3% SSBA-15 membrane as compared with Nafion 117 ® .

Francisco Javier Rodriguez Valadez, Catalina Gonzalez Nava

ECS Meeting Abstracts • 2014

Microbial fuel cell (MFC) are bioelectrochemical system using exoelectrogenic microorganisms to produce electricity, electrons are transferred through a biofilm growth on the anode surface (Sund et al., 2007), the humic acid had optimal biofilm formation, reducing the lag-time and improve the performance of the MFCs. The aim of this work was to evaluate the effect of humic acid addition on the performance of MFC. The biofilm growth with and without humic acid was evaluated by cyclic voltammetry (CV), chronopotentiometry at open circuit potential and scanning electron microscopy (SEM), the performance of MFC was evaluated by polarization curves and values of voltage, current density and power density achieved with data acquisition system. Triplicate measurements made in a MFC with two chambers of 375 mL, carbon cloth electrodes and proton exchange membrane. From the 5th day, the MFC without humic acid showed a voltage of 0.1 V in response to biofilm wrowth and a steady voltage of 0.34 V after 40 days, cyclic voltammetry showed reduction signs in -0.284 to 0.259 V Vs SHE and oxidation signs in -0.643 to 0.060 V Vs SHE, showing electroactivity biofilms. Optimal biofilm formed reduce the internal resistance from 50 to 4.5 kµÙ, also the anode potential changed from -0.251 to -0.512 V Vs SHE for better performance of MFC. The MFC showed a maximum power density of 1.78E-03 W/m 2 , current density of 3.6 mA/m 2 and power density of 1.4 W/m 2 . The optimal biofilm formation is important for the performance of MFCs (Martin et al., 2013) and humic acid had effect on the electrode surface supported the growth of biofilm due to functional groups with redox properties (Wandruszka Palmer, 2010). References Sund et al., 2007. Appl Microbiol Biotechnol. 76, 561-568. Palmer y Wandruszka, 2010. Environmental Science & Pollution Research. 17, 1362-1370. Martin et al., 2013. J. Appl. Electrochem. DOI 10.1007/510800-013-0537-2.