Fuel Cell Hybrid System Research Articles

Thermoeconomic analysis of a fuel cell hybrid power system from the fuel cell experimental data

An innovative configuration of fuel cell technology is proposed based on a hybrid fuel cell system that integrates a turbogenerator to overcome the intrinsic limitations of fuel cells in conventional operation. An analysis is done of the application of molten carbonate fuel cell technology at the Guadalix Fuel Cell Test Facility, for the assessment of the performance of the fuel cell prototype to be integrated in the Hybrid Fuel Cell System. This is completed with a thermoeconomic analysis of the 100 kW cogeneration fuel cell power plant which was subsequently built. The operational results and design limitations are evaluated, together with the operational limits and thermodynamic inefficiencies (exergy destruction and losses) of the 100 kW fuel cell. This leads to the design of a hybrid system in order to demonstrate the possibilities and benefits of the new hybrid configuration. The results are quantified through a thermoeconomic analysis in order to get the most cost-effective plant configuration. One promising configuration is the MCFC topper where the fuel cell in the power plant behaves as a combustor for the turbogenerator. The latter behaves as the balance of plant for the fuel cell. The combined efficiency increased to 57% and NOx emissions are essentially eliminated. The synergy of the fuel cell/turbine hybrids lies mainly in the use of the rejected thermal energy and residual fuel from the fuel cell to drive the turbogenerator in a 500 kW hybrid system.

Hybrid Fuel-Cell Strategies for Clean Power Generation

A hybrid power system consists of a combination of two or more power generation technologies to make best use of their operating characteristics and to obtain efficiencies higher than that could be obtained from a single power source. Since fuel cells directly convert fuel and an oxidant into electricity through an electrochemical process, they produce very low emissions and have higher operating efficiencies. Hence, combining fuel cells with other sources, the efficiency of the combined system can be further increased or extend the duration of the available power to the load as a backup power. In this paper, different types of fuel-cell hybrid systems and their applications are presented. An analysis of the combined cycle operation of a solid oxide fuel cell (SOFC)-microturbine is presented. A strategy for combining the thermophotovoltaic power generation unit and SOFC to obtain the hybrid power system that would have higher efficiency is proposed. The hybrid operation of wind power and solar power system with proton exchange membrane fuel cell is also presented.

G122 ガスタービン・固体酸化物形燃料電池ハイブリッドシステムの性能に対する燃料組成の影響(一般セッション 燃料電池II)

G122 ガスタービン・固体酸化物形燃料電池ハイブリッドシステムの性能に対する燃料組成の影響(一般セッション 燃料電池II)

A wind-power fuel-cell hybrid system study on the non-interconnected Aegean islands grid

The current paper presents the study of coupling a wind-turbine with a fuel cell to improve the utilization of wind power in the non-interconnected Greek archipelago grid. A part of the energy produced by the wind-turbine is stored in the form of hydrogen and is then delivered to the consumption at constant power through a fuel cell. This decoupling between the wind potential and power delivery is necessary to increase the contribution of renewable energy sources to the small capacity grids of islands. The study presents the technology of the system and simulates its operation over a year using a specially developed software and actual wind speed input data. In this way, the energy availability can be estimated and is presented for hybrid installations of increasing size. The nominal size of the individual devices (electrolyser, fuel cell, hydrogen storage tanks) is then selected depending on the hybridisation level, that is the ratio of energy delivered directly from the wind-turbine over the energy delivered from the fuel cell. Results show that it is possible to replace conventional power stations with a hybrid system, delivering energy under constant power with fuel cell sizes that reach almost up to 1/3 of the nominal wind-turbine power and overall efficiencies that may exceed 60%.

Development of Fuel-Cell Hybrid System

Toyota Motor Corporation started the development of fuel cell vehicle in 1992, and the company began leasing a new generation fuel cell vehicle the FCHV(Fuel Cell Hybrid Vehicle) in December 2002.The FCHV's system is designed to improve the efficiency and aims for high responsiveness when the vehicle is in a transitional state. In much the same way as most electric vehicles and the gasoline powered hybrid “Prius”, the energy the traction motor creates during braking can be used to regenerate the secondary battery. The fuel cell and traction motor inverter are connected directly, with the secondary battery connected through the DC/DC converter to the fuel cell in parallel. The efficiency of the FCHV has the ability to be approximately 3 times greater than the conventional internal combustion engine (ICE) powered vehicle.In 2003, Toyota developed the highly efficient next-generation FCHV. The system uses a lithium battery, the optimum power storage device for the characteristics of the fuel cell system, and a highly efficient half bridge converter circuit. The change to a lighter secondary battery and the reduction of converter losses make it possible to improve the fuel economy by 4% over the current Toyota FCHV.This paper describes the circumstances of fuel cell vehicle development in Toyota and the overview of Toyota FCHV's system control and next-generation FCHV's system.

マイクロガスタービン・固体酸化物形燃料電池ハイブリッドシステムによるコージェネレーションシステムの最適運用シミュレーション(エネルギー有効利用(2),空気調和・冷凍・エネルギー有効利用技術)

マイクロガスタービン・固体酸化物形燃料電池ハイブリッドシステムによるコージェネレーションシステムの最適運用シミュレーション(エネルギー有効利用(2),空気調和・冷凍・エネルギー有効利用技術)

Proposal of the Atmospheric Pressure Turbine (APT) and High Temperature Fuel Cell Hybrid System

Solid oxide fuel cell (SOFC) has been extensively developed in many countries as an ultra-high efficient energy converter. Such high temperature fuel cell can be operated as a hybrid system of integrating of turbo machinery. A major decision is whether to place the cell stack in pressurized or unpressurized section. This paper discusses the exhaust energy recovery from fuel cells by use of turbo machines under unpressurized conditions, working with inverted Brayton cycle in which turbine expansion, cooling by heat exchanger and draft by compressor are made in an open cycle mode. It is denoted as “atmospheric pressure turbine (APT)”.

An Interface Construction of Fuel Cell and Battery Hybrid System

This paper describes an interface method to utilize the hybrid system with fuel cell and battery. The hybrid system has unique advantage to manage energy state between high energy system (fuel cell) and high power system (battery) according to various type ofload. First, the hybrid system is completely modelled and simulated by using Simplorer. The models are sufficiently correct by considering many parameters. Interface method is realized by constructing a DC-DC converter, and experimented under various load conditions.

Simulation of a 220 kW Hybrid SOFC Gas Turbine System and Data Comparison

The advancement of efficient hybrid fuel cell systems requires the evolution of analysis strategies for evaluating and developing cycle design. This paper addresses the performance of a recently developed simulation tool for the analysis of tubular SOFC power systems as compared to observed hybrid operation data. Descriptions of the Advanced Power Systems Analyses Tools (APSAT) modeling package and of the world's first hybrid SOFC gas turbine system are presented. Through simulation of the Siemens Westinghouse 220 kW hybrid the analysis program is evaluated to verify the simulation capability and accuracy of the tool. Results show that the APSAT program predicts electrical power generation and efficiency (net AC/LHV) that are in line with observed performance data. In addition, the tool accurately predicts key process temperatures throughout the system. Finally, sensitivity analyses of several major system parameters were accomplished to identifying key development needs and improvement potential for hybrid SOFC gas turbine cycles.

Analysis Strategies for Tubular Solid Oxide Fuel Cell Based Hybrid Systems

The emergence of fuel cell systems and hybrid fuel cell systems requires the evolution of analysis strategies for evaluating thermodynamic performance and directing design and development. A description and application of the recently developed tool for analyzing tubular SOFC based systems is presented. The capabilities of this tool include an analytical model for the tubular SOFC derived from first principles and the secondary equipment required to analyze hybrid power plants. Examples of such secondary equipment are gas turbine, reformer, partial oxidation reactor, shift reactor, humidifier, steam turbines, compressor, gas expander, heat exchanger, and pump. A “controller” is included which is essential for modeling systems to automatically iterate in order to meet the desired process or system design criteria. Another important capability that is included is to be able to arrange the various components or modules as defined by the user in order to configure different hybrid systems. Analysis of the hybrid cycle as originally proposed by Westinghouse (SureCell TM) indicates that the thermal efficiency of the cycle is quite insensitive to the pressure ratio, increasing from 65.5 percent to 66.6 percent on a lower calorific value of the fuel as the pressure ratio decreases from 15 to 6.5.

Cycle Optimization and High Performance Analysis on the Hybrid Gas Turbine and Fuel Cell Systems.

Cycle Optimization and High Performance Analysis on the Hybrid Gas Turbine and Fuel Cell Systems.

Two-loop controller for maximizing performance of a grid-connected photovoltaic-fuel cell hybrid power plant

Maximizing performance of a grid-connected photovoltaic (PV)-fuel cell hybrid system by use of a two-loop controller is discussed. One loop is a neural network controller for maximum power point tracking, which extracts maximum available solar power from PV arrays under varying conditions of insolation, temperature, and system load. A real/reactive power controller (RRPC) is the other loop. The RRPC achieves the system's requirements for real and reactive powers by controlling incoming fuel to fuel cell stacks as well as switching control signals to a power conditioning subsystem. Results of time-domain simulations prove not only the effectiveness of the proposed computer models of the two-loop controller but also its applicability for use in stability analysis of the hybrid power plant.

The generalised Huggins-Mayer form of born repulsive potentials for NaCl-type alkali halides

This paper reports a review of an environmentally clean and efficient source of energy such as solid oxide fuel cell hybrid systems. Due to climate concerns, most nations are seeking alternative means of generating energy from a clean, efficient and environmental-friendly method. However, this has proven a big hurdle for both academic and industry researchers over many years. Currently, practical and technically feasible solution can be obtained via an integration of a microturbine and a fuel cell (hybrid systems). Combining the two distinct systems in a hybrid arrangement the efficiency of the microturbine increases from 25 to 30% to the 60–65% range. Hence, this paper outlines an engineering power generation solution towards the acute global population growth, the growing need, environmental concerns, intelligent use of energy with attendant environmental and hybrid system layouts concerning arising problems and tentative proposed solutions. Furthermore, advantages of a solid oxide fuel cell hybrid systems with respect to the other technologies are identified and discussed rationally. Special attention is devoted to modelling with software and emulator rigs and system prototypes. The paper also reviews the limitations and the benefits of these hybrid systems in relationship with energy, environment and sustainable development. Few potential applications, as long-term potential actions for sustainable development, and the future of such devices are further discussed.