SOFC Micro-CHP integration in residential buildings

SOFC technology has reached many of the performance goals that where indicated by scientific society and is providing several application that permits market penetration. One of the main targets is related to Micro Cogeneration Heat and Power (μ-CHP) for residential application. The integration of this system with a residential house has to be deeply investigated to individuate market targets in terms of costs and efficiency. This study evaluates the Italian market condition and analyzes the integration possibility with both thermal and electrical systems. Different solutions are investigated evaluating thermal and electrical driven logic for μ-CHP SOFC based unit and the opportunity of integration with local electrical grid. Evaluation on heat and electricity storage was also considered as integration strategy. The study is based on electrical and thermal loads in typical residential users and the evaluation is based on Italian technical standards and guidelines. Several operating conditions were evaluated and compared to obtain an optimized size and integration of μHP SOFC based solution

Experimental Comparison and Performance Evaluation of Planar Solid Oxide Single Cell

Nowadays, in a world characterized by the need to reduce the production of pollutants, by global climate changes, by the progressive lack of availability of cheap fossil fuels, one of the most important goals of scientific research is to design systems that can provide energy with low environmental impact. Planar Solid Oxide Fuel Cells (SOFC) are considered to be power generators with high efficiency independent on size and low emissions. Fuel cell laboratory (FCLab) of University of Perugia has focused his studies on SOFC operating at high temperature (800–1000°C), characterized by greater flexibility in the choice of fuel. This study focuses on definition and realization of experimental test able to define the quality of a SOFC single cell and on the effect of test condition parameter. The performance of the cell is evaluated via polarization curves realized in different external conditions. Area Specific Resistance (ASR) is used as main test output. Results analysis confirm that ASR gives important information on fuel cell performance and can be used to compare an qualify SOFC single cell

Characterization of 300 W SOFC stack fed by different fuels

The rapid growth in terms of efficiency and performance of the solid oxide fuel cell (SOFC) technology in recent years has led SOFC to be one of the possible solutions for the exploitation of different types of fuels obtained from fossil or renewable sources. A lot of processes, such as waste incineration or anaerobic digestion, during operation produce exhaust gases that can be efficiently exploited in SOFC systems. SOFCs, thanks to their operating condition, run with standard fuels such hydrogen and methane as well as fuel waste gas, like biogas or landfill gas, or gas plant, like pyrogas. The aim of this work is to compare the performance of an 100W stack SOFC when it is fed by different fuel compositions

Carbon capture with molten carbonate fuel cells: Experimental tests and fuel cell performance assessment

Molten carbonate fuel cells (MCFCs) may operate as CO2 separators and concentrators while generating electric power, being thus a very interesting candidate to be used as carbon capture systems in fossil fired power plants.The main aim of this work is to understand the MCFC performance, its potential and efficiency to separate CO2 from the exhaust gas of fossil fired power plants and the effect of critical parameters such as the cathodic carbon dioxide concentration (XCO2) and utilization (UCO2), as well as the partial pressure ratio between oxygen and carbon dioxide (PO2/PCO2) and other parameters such as the oxygen concentration (XO2), utilization (UO2) and the total cathodic flow rate (Qcat). This was achieved by studying the experimental behaviour of a single MCFC when it is fed with a mixture simulating the composition of the exhaust gases of a combined heat and power plant, in order to point out potential limitations in the fuel cell operating conditions.In particular, the carbon dioxide concentration in the cathodic section was shown to be a critical factor at low values, that can both induce quick voltage drops and make the cell sensitive to the other parameters, which are otherwise not so important

Thermal transients modelling of a reformer unit for diagnostic analysis of SOFC-based systems

Solid oxide fuel cell-based systems constitute one of the most promising technologies for future power generation. In order to make them marketable, many issues as durability and operational management have to be overcome. Therefore the understanding of thermodynamic and chemical mechanisms, that govern SOFC BoP components (beyond that the stack one) behaviour in both steadystate and transient operation, becomes fundamental. In this context, after stack dynamic analysis [1] and investigations relative to SOFC-based systems [2,3], the study was extended to the methane steam reformer unit, with particular attention to its dynamic thermal behaviour. In particular the overall analysis methodology and the required experimental campaign were defined as described in the following. Future work will deal with the execution of all the scheduled tests and the model setup according to the developed methodology

Characterization of a 100 W SOFC stack fed by carbon monoxide rich fuels

This paper presents the evaluation of the performance of a 100 W Solid Oxide Fuel Cell (SOFC) stack with CO rich fuels as anode gas. The study aims at measuring the Open Circuit Voltage (OCV) and the Area Specific Resistance (ASR) when the amount of CO in the anode flow varies from 0 to 40% in volume. At the same time, the FCTestQA procedures were applied and evaluated as methodology for Solid Oxide Fuel Cell testing. The theoretical OCV was measured considering both H2 and CO oxidation and the water gas shift reaction. The OCV values, as a function of CO concentration, resulted closely related to theoretical ones and the ASR value, calculated for different mixtures of fuel, did not change with anode gas composition and it seemed to be a function of the temperature and the degradation of the materials only

ADSORPTIVE REMOVAL OF H2S IN BIOGAS CONDITIONS FOR HIGH TEMPERATURE FUEL CELL SYSTEMS

Desulphurization represents a crucial step in fuel processing for high temperature fuel cell applications, because of the stringent requirements of fuel cell catalysts. Moreover, when fuel cell stacks are used in a micro-CHP system, the necessity to realize an efficient and compact system is mandatory. The possibility to use a renewable energy source, as biogas from anaerobic digestion instead of natural gas, to feed a fuel cell stack, could have a significant impact in terms of fossil fuels saving and environmental conservation. In this work, desulphurization tests for H2S removal are carried out in biogas conditions, using commercial adsorbents, like activated carbons (AC), activated alumina, zeolite and sepiolite. The first part of the test campaign was focused on the definition of the material characterized by the best performance in terms of H2S adsorption capacity. Then, the influence on adsorption capacity of operating parameters, such as gas hourly space velocity (GHSV), humidity (Relative Humidity 50%) and gas matrix composition (N2, CH4, CO2 and a mixture of CH4 and CO2) was investigated, in order to obtain a compact filter with high removal activity