Who are the early adopters of fuel cell vehicles?

All new technologies, including automotive technologies, are first purchased by early adopters. These consumers are currently posed with the choice of purchasing a fuel cell vehicle (FCV) or a variety of other alternatively fueled vehicles, including battery electric vehicles (BEVs). For FCVs to be commercially successful they need to carve out their own niche in the automotive market, something which may prove challenging in the face of strong BEV market growth. The results in this paper come from a questionnaire survey of 470 FCV owners and 1550 BEV owners. The paper explores the socio-economic profile, travel patterns, and attitudes of FCV buyers and compares them to the buyers of BEVs. The result suggests that the adopters of BEVs and FCV are similar in gender, level of education, household income, and have similar travel patterns. They have differences in age, ownership of previous alternative fuel vehicles, attitudes towards sustainability, and more FCV owners live in rented homes and apartment buildings. The results of the study suggest that FCVs may appeal to consumers who live in homes where they cannot recharge a BEV or install their own charger. FCVs still have several challenges to overcome, including the lack of hydrogen refueling stations and a lack of FCV models to choose from.     

Fabrication and testing of a H2–O2 fuel cell using MoxRuySez

We report the results obtained in the preparation and characterization of Mo_xRu_ySe_z electrocatalysts for oxygen reduction reaction and the design, construction and characterization of a H₂–O₂ fuel cell using Mo_xRu_ySe_z. The catalysts were characterized with respect to their electrocatalytic properties. The fuel cell was designed and built with Mo_xRu_ySe_z supported on carbon as cathode, Pt supported on carbon as anode, and H₂SO₄ as the electrolyte. The fuel cell was tested at room temperature and atmospheric pressure. The H₂–O₂ cell showed an efficiency in the order of 30%.     

Energy efficiency of membrane-based fuel processors – PEM fuel cell systems

This work presents a simulative energy efficiency analysis performed on fuel processor – PEMFC systems, considering methane as fuel and steam reforming or autothermal reforming as processes to produce hydrogen. Computation of energy efficiency takes into account the power required by the auxiliary units, coupling of the fuel processor with the fuel cell as well as heat recovery and integration.     

Investigation of failed tubes from ‘B’ steam generator of the R. E. Ginna nuclear power plant

An investigation was performed on various steam generator tubes from the R. E. Ginna nuclear power plant (Rochester Gas and Electric). These tubes were involved in the loss of coolant accident of January 1982. The report concludes that the loss of coolant accident was the result of a purely mechanical mechanism caused by an adjacent severed tube rubbing the outer surface of tube R42-C55 until its cross-section was insufficient to withstand the primary to secondary side pressure differential. The initial severing of the adjacent tubes is considered to have been caused by the impacting of one or more carbon steel foreign objects on the outer periphery tubes in the ‘B’ steam generator.     

Quasi-stationary UI-characteristic model of a PEM fuel cell–Evaluating the option of self-humidifying operation

This work presents a zero-dimensional PEM fuel cell UI-characteristic model created in MATLAB Simulink® for operation with dry or humidified air supply. It is parameterised and validated based on the results of stack operation by varying stack temperature (50–80 °C), gas pressure (1.0–2.4 bar) and air humidification (0.0–1.0). The model is based on physical and electrochemical correlations and expanded by empirically assumptions concerning the influence of the humidification and limiting current density on the performance. The UI-model is intended to be integrated into a comprehensive zero-emission powertrain model. Since non-humidified operation of PEM fuel cell systems provides benefits for mobile applications by reducing space demand and system complexity, the objective of the model is to relate performance to the operating conditions and underlying physical parameters. Results confirm the feasibility of a self-humidifying stack operation at high performance by optimal parameter setting.     

Portable fuel cell systems for America’s army: technology transition to the field

The US Army Communications, Electronics Research Development and Engineering Center (CERDEC) envisions three thrust areas for portable fuel cell systems for military applications. These areas include soldier power (<500 W), sensor power (0–100 W), and auxiliary power units or APUs (0.5–10 kW). Soldier and sensor fuel cell systems may be man-portable/backpackable while APUs could be employed as squad battery chargers or as ‘Silent Watch’ APUs where low signature (acoustic, thermal, etc.) operation is a requirement.The Army’s research and development efforts are focusing on methods of either storing or generating hydrogen on the battlefield. Hydrogen storage technology is considered critical to small military and/or commercial fuel cell systems, and is being pursued in a host of commercial and government programs. CERDEC, in a joint effort with the Army Research Office (ARO) and the Defense Advanced Research Projects Agency (DARPA), is developing several promising hydrogen generating technologies. The goal of this program is a safe, reliable hydrogen source that can provide rates up to 100 W with an energy density of greater than 1000 Wh/kg.For larger fuel cell units (>500 W), it is imperative that the fuel cell power units be able to operate on fuels within the military logistics chain [DOD 4140.25-M, DOD Directive 4140.25 (1993)]. CERDEC is currently conducting research on catalysts and microchannel fuel reformers that offer great promise for the reforming of diesel and JP-8 fuels into hydrogen. In addition to research work on PEM fuel cells and enabling technologies, the Army is also conducting research on direct methanol and solid oxide fuel cells, and combined heat and power applications utilizing new high temperature fuel cells.     

Effect of anode conditions on the performance of direct borohydride–hydrogen peroxide fuel cell system

Direct borohydride–hydrogen peroxide fuel cells (DBHPFCs) are attractive power sources for space applications. Although the cathode conditions are known to affect the system performance, the effect of the anode conditions is rarely investigated. Thus, in this study, a DBHPFC system was tested under various anode conditions, such as electrocatalyst, fuel concentration, and stabilizer concentration, to investigate their effects on the system performance. A virtual DBHPFC system was analyzed based on the experimental data obtained from fuel cell tests. The anode electrocatalyst had a considerable effect on the mass and electrochemical reaction rate of the fuel cell system, but had minimal effect on the decomposition reaction rate. The NaBH₄ concentration greatly influenced the mass and decomposition reaction rate of the fuel cell system; however, it had minimal impact on the electrochemical reaction rate. The NaOH concentration affected the electrochemical reaction rate, decomposition reaction rate, and mass of the fuel cell system. Therefore, the significant effects of the anode conditions on the electrochemical reaction rate, decomposition reaction rate, and mass of the fuel cell system prompt the need for their careful selection through fuel cell tests and system analysis.     

Direct methanol fuel cell systems for backup power – Influence of the standby procedure on the lifetime

This paper compares different backup power systems for uninterruptible emergency power supply (UPS) in the kW-power range. The cost structure of direct methanol fuel cell systems (DMFCs) is deduced from a DMFC system developed for the replacement of batteries in small fork-lift trucks. The setup for new DMFC backup power systems will be further simplified and those systems will be operated without expensive sensors necessary for laboratory testing. A detailed cost structure of such systems is shown, and in a cost comparison the competitiveness to other existing UPS technologies is indicated.In spite of reduced sensor systems the efficient and secure operation of the system must be guaranteed. The demanded durability in case of UPS is ten years in discontinuous operation. To achieve the long term stability the right treatment of the stack during standby was identified by tests on single cells as well as on short stacks. A number of different standby procedures have been tested in order to identify how the MEAs must be treated in order to avoid premature degradation during standby.     

Performance of supported Au–Co alloy as the anode catalyst of direct borohydride-hydrogen peroxide fuel cell

Au–Co alloys supported on Vulcan XC-72R carbon were prepared by the reverse microemulsion method and used as the anode electrocatalyst for direct borohydride-hydrogen peroxide fuel cell (DBHFC). The physical and electrochemical properties were investigated by energy dispersive X-ray (EDX), X-ray diffraction (XRD), cyclic voltammetry, chronamperometry and chronopotentiometry. The results show that supported Au–Co alloys catalysts have higher catalytic activity for the direct oxidation of BH₄⁻ than pure nanosized Au catalyst, especially the Au₄₅Co₅₅/C catalyst presents the highest catalytic activity among all as-prepared Au–Co alloys, and the DBHFC using the Au₄₅Co₅₅/C as anode electrocatalyst shows as high as 66.5 mW cm⁻² power density at a discharge current density of 85 mA cm⁻² at 25 °C.     

How risky is the introduction of fuel cell electric vehicles in a Mediterranean town?

The incorporation of Fuel Cell Electric Vehicles (FCEVs) in public transport is a fundamental step towards the minimization of the emissions due to transportation globally. In-depth studies are required regarding the potential risk from the storage of hydrogen, the transportation of hydrogen to refuelling stations and the refuelling procedure. Thus, it is a prerequisite to establish a holistic baseline which is related to FCEV safety during operation/maintenance, especially to a country in which the sales of these types of vehicles are significantly low. This paper suggests the employment of operational risk management methodology. Relevant experts and stakeholders requested to fill out an ‘‘Event-Probability Matrix’’ per scenario of likely hazards. This research estimates the interest of the local society about technological hazards and the conviction that hydrogen vehicles could be as safe as conventional vehicles. Additional critical scenarios related to the hydrogen storage are analyzed.     

Thermodynamic analysis of ethanol processors – PEM fuel cell systems

This work presents a simulative energy efficiency analysis performed on fuel processor – PEM fuel cell systems, considering ethanol as fuel and steam reforming or autothermal reforming as processes to produce hydrogen.     

Analytical modeling of PEM fuel cell i–V curve

The performance of a fuel cell is characterized by its i–V curve. In this study, the performance of a bench scale fuel cell stack, run on hydrogen/air, is measured experimentally for different air flow rates and temperatures. The experimental data, obtained from the 40-W proton exchange membrane fuel cell (PEMFC), are used in estimating the parameters of a completely analytical model that describes the i–V curve. The analytical model consists of the three fundamental losses experienced by a fuel cell, namely: activation, ohmic, and concentration losses. The current loss is also considered in the model. While the Tafel constants, ohmic resistance, and the concentration loss constant are estimated through regression, the limiting current density and the current loss are obtained through measurements. The effect of temperature on the fuel cell performance, exchange current density, and current loss is also investigated. Both the exchange current density and the current loss are plotted against temperature on an Arrhenius-like plot and the related parameters are estimated. The theoretical equations derived in the literature, which model fuel cell performance, are found to reasonably fit the obtained experimental data.     

The affects of membrane on the cell performance when using alkaline borohydride–hydrazine solutions as the fuel

The cell performance and the polarization behavior of the fuel cell using alkaline NaBH₄–N₂H₄ solutions as the fuel were investigated. It was found that the use of different membrane: anion exchange membrane (AEM) or cation exchange membrane (CEM) would influence the cell performance and cathode polarization behavior. The direct borohydride fuel cell (DBFC) using CEM gave a higher power density than that using AEM, but the direct hydrazine fuel cell (DHFC) using CEM gave a lower power density compared with the DHFC using AEM. In the DBFCs using CEM, N₂H₄ addition in alkaline NaBH₄ solution improved the cell performance but it did not make any difference when adding more N₂H₄. On the other hand, in the DBFCs using AEM, cell performance was improved with increasing the amount of N₂H₄ in the anolyte.     

Study of molten carbonate fuel cell—microturbine hybrid power cycles

The interaction realized by fuel cell—microturbine hybrids derive primarily from using the rejected thermal energy and combustion of residual fuel from a fuel cell in driving the gas turbine. This leveraging of thermal energy makes the high temperature molten carbonate fuel cells (MCFCs) ideal candidates for hybrid systems. Use of a recuperator contributes to thermal efficiency by transferring heat from the gas turbine exhaust to the fuel and air used in the system.Traditional control design approaches, consider a fixed operating point in the hope that the resulting controller is robust enough to stabilize the system for different operating conditions. On the other hand, adaptive control incorporates the time-varying dynamical properties of the model (a new value of gas composition) and considers the disturbances acting at the plant (load power variation).     

Strategy of innovations and investments for the modernization of Ukraine’s fuel and energy complex

The most relevant strategic methods of innovation for the modernization of Ukraine’s fuel and energy complex and rational investment options are considered.     

Coupled continuum and condensation–evaporation pore network model of the cathode in polymer-electrolyte fuel cell

A model of the cathode side of a Proton Exchange Membrane Fuel Cell coupling the transfers in the GDL with the phenomena taking place in the cathode catalyst layer and the protonic transport in the membrane is presented. This model combines the efficiency of pore network models to simulate the liquid water formation in the fibrous substrate of the gas diffusion layer (GDL) and the simplicity of a continuum approach in the micro-porous layer (MPL). The model allows simulating the liquid pattern inside the cathode GDL taking into account condensation and evaporation phenomena under the assumption that the water produced by the electro-chemical reactions enters the MPL in vapor form from the catalyst layer. Results show the importance of the coupling between the transfers within the various layers, especially when liquid water forms as the result of condensation in the region of the GDL fibrous substrate located below the rib.     

Modeling and simulation of solid oxide fuel cell based on the volume–resistance characteristic modeling technique

Solid oxide fuel cell (SOFC) is a complicated system with heat and mass transfer as well as electrochemical reactions. The real-time dynamic simulation of SOFC is still a challenge up to now. This paper develops a one-dimensional mathematical model for direct internal reforming solid oxide fuel cell (DIR-SOFC). The volume–resistance (V–R) characteristic modeling technique is introduced into the modeling of the SOFC system. Based on the V–R modeling technique and the modular modeling idea, ordinary differential equations meeting the quick simulation are obtained from partial differential equations. This model takes into account the variation of local gas properties. It can not only reflect the distributed parameter characteristics of SOFC, but also meet the requirement of the real-time dynamic simulation. The results indicate that the V–R characteristic modeling technique is valuable and viable in the SOFC system, and the model can be used in the quick dynamic and real-time simulation.     

Performance analysis for the part-load operation of a solid oxide fuel cell–micro gas turbine hybrid system

In this paper, the performance evaluation of a solid oxide fuel cell (SOFC)–micro gas turbine (MGT) hybrid power generation system under the part-load operation was studied numerically. The present analysis code includes distributed parameters model of the cell stack module. The conversions of chemical species for electrochemical process and fuel reformation process are considered. Besides the temperature distributions of the working fluids and each solid part of cell module by accounting heat generation and heat transfers, are taken into calculation. Including all of them, comprehensive energy balance in the cell stack module is calculated. The variable MGT rotational speed operation scheme is adopted for the part-load operation. It will be made evident that the power generation efficiency of the hybrid system decreases together with the power output. The major reason for the performance degradation is the operating temperature reduction in the SOFC module, which is caused by decreasing the fuel supply and the heat generation in the cells. This reduction is also connected to the air flow rate supplement. The variable MGT rotational speed control requires flexible air flow regulations to maintain the SOFC operating temperature. It will lead to high efficient operation of the hybrid system.     

Boosting performance of the solid oxide fuel cell by facile nano-tailoring of La0.6Sr0.4CoO3-δ cathode

Sluggish kinetics for oxygen reduction reaction (ORR) is one of the greatest challenges limiting the electrochemical performance of solid oxide fuel cells (SOFCs). Surface modification through solution infiltration is recognized as a promising approach to boost the performance of the SOFCs. The conventional infiltration of electrocatalyst in porous scaffold results in discrete particles of active catalyst. However, in this study, we report a novel technique to produce the nano-tailored film of Sm_0.5Sr_0.5CO_3-δ (SSC) active catalyst on to La_0.6Sr_0.4CoO_3-δ (LSC) cathode of SOFC through controlling the drying rate during the infiltration process which resulted in a continous film like coating of SSC. The SOFC with LSC cathode containing SSC film-like nanostructure showed a two-fold performance increment and an excellent durability compared to the LSC cathode prepared through conventional methods. The higher performance of the film-like nanostructured LSC-SSC cathode is attributed to the remarkable reduction in the area-specific ohmic and polarization resistance due to the extension of cathode reaction sites and shorter diffusion lengths, thus, facilitating the ORR.     

Effect of fiber orientation on Liquid–Gas flow in the gas diffusion layer of a polymer electrolyte membrane fuel cell

In this study, the lattice Boltzmann method was used to simulate the three-dimensional intrusion process of liquid water in the gas diffusion layer (GDL) of a polymer electrolyte membrane fuel cell (PEMFC). The GDL was reconstructed by the stochastic method and used to investigate fiber orientation's influence on liquid water transport in the GDL of a PEMFC. The fiber orientation can be described by the angle between a single fiber and the in-plane direction; three different samples were simulated for three different fiber orientation ranges. The simulated permeability correlated well with the anisotropic characteristics of reconstructed carbon papers. It was concluded that the fiber orientation had a significant effect on the liquid invasion pattern in the GDL by changing the pore shape and distribution of the GDL. The results indicated that the stochastically reconstructed GDL, taking into account the fiber orientation, better demonstrates the mass transport properties of the GDL.