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Number of results: 8
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Abstract

The application of renewable energy sources poses the problems connected with output volatility. In order to decrease this effect the energy storage technologies can be applied, particularly fuel cells connected with hydrogen storage. In this paper the application of SOFC system for a household in Poland is proposed. Economic and technical analysis is performed. It was found that the proposed installation is profitable after 25 years of operation when compared with conventional solution - heat pumps and gas-fired boilers.
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Abstract

On May 17, 2018, the National Center for Research and Development announced the initiation of a new procedure within the Hydrogen Storage Program. The objective was to develop a Hydrogen Storage System for use with fuel cells and its demonstration in a Mobile Facility. This is to create an alternative to the use of fossil fuels and create a field for competition in creating solutions in the field of access to “clean” energy. The National Center for Research and Development is responsible for the development of assumptions, regulations and implementation. The analysis presents the main assumptions of the program is correlated to the current legal situation related to the financing of Research and Development. An in-depth study concerns the ways of using innovative partnership and its placement in the system of European Union legal acts. The idea of the pre-commercial procurement procedure (Pre-Commercial Procurement), which was developed to support the implementation of prototypes of solutions – resulting from research and development – with a high potential for possible commercialization, was described in details. This procedure is characterized by ensuring the financing of a product or service at an early stage of development. Although this creates the risk of failure of the project, it stimulates technological development.
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Abstract

Among the numerous modern, high-efficiency energy technologies allowing for the conversion of chemical energy of coal into electricity and heat, the Direct Carbon Fuel Cells (DCFC) deserve special attention. These are devices that allow, as the only one among all types of fuel cells, to directly convert the chemical energy contained in solid fuel (coal) into electricity. In addition, they are characterized by high efficiency and low emission of pollutants. The paper reviews and discusses previous research and development works, both around the world and in Poland, into the technology of direct carbon fuel cells with an alkaline (hydroxide) electrolyte.
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Abstract

This paper discusses the transient characteristics of the planar type SOFC cell stack, of which the standard output is 300 W. The transient response of the voltage to the manipulation of an electric current was investigated. The effects of the response and of the operating condition determined by the operating temperature of the stack were studied by mapping a current-voltage (I-V) correlation. The current-based fuel control (CBFC) was adopted for keeping the fuel utilization factor at constant while the value of the electric current was ramped at the constant rate. The present experimental study shows that the transient characteristics of the cell voltage are determined by primarily the operating temperature caused by the manipulation of the current. Particularly, the slope of the I-V curve and the overshoot found on the voltage was remarkably influenced by the operating temperature. The different values of the fuel utilization factor influence the height of the settled voltages. The CBFC has significance in determining the slope of the I-V characteristic, but the different values of the fuel utilization factor does not affect the slope as the operating temperature does. The CBFC essentially does not alter the amplitude of the overshoot on the voltage response, since this is dominated by the operating temperature and its change is caused by manipulating the current.
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Abstract

The paper describes factors influencing the development of electricity storage technologies. The results of the energy analysis of the electric energy storage system in the form of hydrogen are presented. The analyzed system consists of an electrolyzer, a hydrogen container, a compressor, and a PEMFC fuel cell with an ion-exchange polymer membrane. The power curves of an electrolyzer and a fuel cell were determined. The analysis took the own needs of the system into account, i.e. the power needed to compress the produced hydrogen and the power of the air compressor supplying air to the cathode channels of the fuel cell stack. The characteristics describing the dependence of the efficiency of the energy storage system in the form of hydrogen as a function of load were determined. The costs of electricity storage as a function of storage capacity were determined. The energy aspects of energy accumulation in lithium-ion cells were briefly characterized and described. The efficiency of the charge/discharge cycle of lithium-ion batteries has been determined. The graph of discharge of the lithium-ion battery depending on the current value was presented. The key parameters of battery operation, i.e. the Depth of Discharge (DoD) and the State of Charge (SoC), were determined. Based on the average market prices of the available lithium-ion batteries for the storage of energy from photovoltaic cells, unit costs of electrochemical energy storage as a function of the DoD parameter were determined.
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Abstract

The present study deals with modelling and validation of a planar Solid Oxide Fuel Cell (SOFC) design fuelled by gas mixture of partially pre-reformed methane. A 3D model was developed using the ANSYS Fluent Computational Fluid Dynamics (CFD) tool that was supported by an additional Fuel Cell Tools module. The governing equations for momentum, heat, gas species, ion and electron transport were implemented and coupled to kinetics describing the electrochemical and reforming reactions. In the model, the Water Gas Shift reaction in a porous anode layer was included. Electrochemical oxidation of hydrogen and carbon monoxide fuels were both considered. The developed model enabled to predict the distributions of temperature, current density and gas flow in the fuel cell.
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Abstract

The aim of this paper was to demonstrate the feasibility of using a Computational Fluid Dynamics tool for the design of a novel Proton Exchange Membrane Fuel Cell and to investigate the performance of serpentine micro-channel flow fields. A three-dimensional steady state model consisting of momentum, heat, species and charge conservation equations in combination with electrochemical equations has been developed. The design of the PEMFC involved electrolyte membrane, anode and cathode catalyst layers, anode and cathode gas diffusion layers, two collectors and serpentine micro-channels of air and fuel. The distributions of mass fraction, temperature, pressure drop and gas flows through the PEMFC were studied. The current density was predicted in a wide scope of voltage. The current density – voltage curve and power characteristic of the analysed PEMFC design were obtained. A validation study showed that the developed model was able to assess the PEMFC performance.
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Abstract

In the 21st century the way to increase the efficiency of new sources of energy is directly related with extended exploration of renewable energy. This modern tendency ensures the fuel economy needs to be realized with nature protection. The increasing of new power sources efficiency (cogeneration, trigeneration systems, fuel cells, photovoltaic systems) can be performed by application of solid sorption heat pumps, regrigerators, heat and cold accumulators, heat transformers, natural gas and hydrogen storage systems and efficient heat exchangers.
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