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

The Influence of Bio-syngas Composition on the Derating of Solid Oxide Fuel Cells☆

Abstract In this work, the performance of solid oxide fuel cells (SOFCs) fed with a syngas obtained from a steam-enriched air gasification of biomass has been investigated, varying the composition of the feeding gas (H2, CO, CO2, CH4, H2O, and N2). The composition has been obtained from experimental/numerical tests in a fluidized bed bench scale gasifier after catalytic steam reforming of the syngas carried out to remove tar. During the gasification tests, the oxygen purity in the enriched air (in the range of 0.2 and 0.9), the gasification process temperature (in the range of 750 and 850 °C), the steam to biomass (in the range of 0.5 and 1) and the equivalence ratio (in the range between 0.0 and 0.4) were varied to simulate the different operating conditions. Commercial SOFC cells have been employed in the experimental campaign, fed with the most representative fuel compositions mentioned above. Polarization curves have been carried out to determine the electrical performance of the cells, comparing the results with cells fed with hydrogen only. In the final paper, the electrochemical impedance spectroscopy (EIS) will be reported for in-depth analysis of the performance parameters and to evaluate the long term degradation rate of the cell

The new Italian SIDAPA Baseline Series for patch testing (2023): an update according to the new regulatory pathway for contact allergens

Allergic contact dermatitis (ACD) is a common inflammatory skin disease caused by delayed hypersensitivity to chemical and biotic contact allergens. ACD significantly affects the patients' quality of life negatively impacting both occupational and non-occupational settings. Patch testing is the gold standard diagnostic in vivo test to precise the ACD etiology and to correctly perform prevention. According to the Italian Medicines Agency (AIFA) legislative decree no. 178 of 29th May 1991, allergens are defined as medicines and therefore they are subject to strict regulation. In 2017, AIFA (decree no. 2130/2017) started a procedure to regulate contact allergens on the Italian market and actually the contact allergens temporarily authorized are reported in AIFA decree no. 98/2022, valid until November 2023. The availability on the market of contact allergens to diagnose ACD and continuous updating on the basis of new epidemiological trends are mandatory, jointly with the continuous update of the baseline and integrative series for patch testing. For this reason, the scientific community represented in Italy by the Skin Allergies Study Group of SIDeMaST (Italian Society of Dermatology and Venereology) and SIDAPA (Italian Society of Allergological, Occupational and Environmental Dermatology) are constantly working, in close relationship with the European scientific communities with large expertise in this important sector of the modern Dermatology. Herein, we report the setting up of regulatory legislation by AIFA and the new Italian Adult Baseline Series for patch testing

Sulphur compounds removal from natural gas using porous materials for high temprature fuel cell applications

Sulfur compounds present as odorants in natural gas like thiophenes,mercaptans,and sulifdes, cuase severe poisoning on high tempreature fuel cell catalysts evev at very low concentration, below 1 ppm. Therefore a deep sulpfur removal from inlet gas mixture is strongly needed and it has to be coupled with an accurate determination of sulfur concentration in the gas stream. Among the different developed filtering solutions, adsorption using porous materials represents a very attractive option, mainly in view of systems simplicity and costs. In this work, adsorptive removal of organic and inorganic sulfur compounds was carried out ina fixed bed floew reactor, using different types of porous materials, such as virgin and impgregnated activated carbons and zeolites. The purpose was to evaluate sorbet capacity of singulkra adsorbents varying process paramaters such as space velocity. The sorbents display differences in adsorpitve capacity among the individual sulfur compounds in natural gas: a comparison among odorants and H2S adsorption is in particular shown. A composite sorbent was realized and tested in order to exploit the selectivity of singular adsorbent materials

Theoretical study and performance evaluation of hydrogen production by 200 W solid oxide electrolyzer stack

High temperature steam electrolyzers, taking advantage of high temperature heat, can produce more hydrogen by using less electrical energy than low temperature electrolyzers. This paper presents an experimental study on hydrogen production by using a 200 W solid oxide stack working in reverse mode. A thermodynamic study of the process was performed by measuring the heat and mass balance of stack at different operating conditions. Different definitions of efficiency were used to highlight the limit and potential of the process. The I–V curve, the flow rate measurements and the GC analysis on outlet flows were used to calculate the hydrogen and oxygen productions. In addition, the influence of steam dilution, water utilization and operating temperature on conversion efficiency and stack's thermal balance was evaluated. With this aim, the tests were performed at three operating temperature (700 °C, 750 °C and 800 °C) over a range of steam inlet concentration from 50% to 90% and water utilization up to 70%. The hydrogen and oxygen flows produced by electrolysis, at different loads, were directly measured after water condensation: net flows up to 2.4 ml/(min cm2) of hydrogen and 1.2 ml/(min cm2) of oxygen were measured and compared to the theoretical ones, showing a good agreement

Experimental Analysis of SOFC Fuelled by Ammonia

In this study, ammonia is presented as a feasible fuel for solid oxide fuel cells (SOFCs). Ammonia has several interesting features as fuel due to low-production cost, high-energy density and, focusing on fuel cells and hydrogen application, ammonia is an excellent H2 carrier thanks to high value of volumetric and gravimetric densities. The paper reports experimental test performed to evaluate the feasibility of NH3 directly fed to a 50 cm2 single cell SOFC. A test plan was developed to compare pure ammonia with an equivalent mix of ammonia, nitrogen, and hydrogen and the study of temperature and voltage values strongly indicates that a two stage oxidation of ammonia can be predicted and a previous cracking reaction occurs in the cell due to the nickel catalytic contribution. The study of temperatures and of heat flows show how the cell is cooled down to lower temperature because of heat adsorbed by the reaction and by flow mix entering the anode. The study shows also how for operative temperatures below 800 °C the cracking reaction takes place in the cell active area. Efficiency test demonstrates that the cell can operate at 300 mW cm–2 and 30% efficiency based on ammonia LHV

EXPERIMENTAL ANALYSIS OF SOFC FUELLED BY AMMONIA

Ammonia (NH3) has very interesting features as fuel for solid oxide fuel cell (SOFC). This study presents preliminary experimental results on a single cell SOFC fueled by ammonia. The study focuses on the cracking reaction that permits to transform ammonia into N2 and H2. This reaction offers to the fuel cell a perfect mix for the operation in safety and efficient conditions. The study compares several polarization curves realized with pure H2, a mix of H2/N2 and a mix of H2/NH3 and pure NH3 at high operation temperature (800°C). The results show how a complete reaction of NH3 can be predicted and an equivalent performance can be obtained substituting the H2/N2 mix with equivalent amount of ammonia