Performance Assessment of Electric Energy Storage (EES) Systems Based on Reversible Solid Oxide Cell

Abstract This paper focuses on the performance assessment of a novel and efficient EES (electric energy storage) system based on ReSOC (reversible solid oxide cell) technology. The ReSOC is an electrochemical energy conversion device working at high temperature (600-1000°C) that can operate reversibly either as a fuel cell (SOFC) or as an electrolyzer (SOEC). In this study, a ReSOC unit fed by mixtures of CH4, CO, H2O and H2 is proposed and analyzed. In particular, in the SOFC mode, where electricity is generated, the reactant gas, mainly formed by CH4 and H2, is converted into a mixture of H2O and CO2. The exhausts from the SOFC are used as the reactant gas for the SOEC operation. During the electrolysis process, CH4 can be also produced thanks to the methanation reaction that, under proper operating conditions, occurs at the cathode of the solid oxide cell. The ReSOC unit behavior is investigated by developing a thermo-electrochemical model, able to predict its performance (i.e. roundtrip efficiency, polarization curve, thermally self-sustaining conditions) under different operating conditions. The ReSOC model, built with a modular architecture, is performed through thermodynamic, thermochemical and electrochemical sub-models taking into account mass and energy balances, chemical reactions (reforming, shifting reactions and methanation) and electro-chemical relationships. Available literature data have been used for the model validation and a calibration procedure has been performed in order to evaluate the best fitting values for the model parameters. Furthermore, in order to estimate the thermoneutral conditions in SOEC operating mode, the ReSOC thermal behavior has been analyzed under different operating temperatures. Results pointed out that, by feeding the cell with a syngas mixture, the reforming reaction (in the SOFC mode) and the methanation reaction (in the SOEC mode) allow to simplify the cell thermal management. Moreover, the best performance in terms of stack roundtrip efficiency (about 70%), can be reached operating the ReSOC at low temperature (700°C)

Conventional and Advanced Biomass Gasification Power Plants Designed for Cogeneration Purpose

Abstract In this paper conventional and advanced biomass gasification power plants designed for small cogeneration application are defined. The CHP plants consist of a gasification unit, that employs a downdraft gasifier, and a power unit based on a microturbine in the case of conventional configuration, and on a solid oxide fuel cell module, in the case of advanced configuration. The plants are sized to supply about 100 kW of electrical power. In order to investigate and to analyze the performances of the two plant configurations, in terms of thermal and electrical efficiencies, numerical models have been developed by using thermochemical and thermodynamic codes

Hydrogen-based hybrid power unit for light vehicles: Assessment of energy performance and radiated electromagnetic emissions

Electrification of transport (electro-mobility) is considered an essential strategy to meet Europe’s climate and energy challenges. Nonetheless, within the future perspective of living in smart cities, the interaction between electromobility devices and the surrounding environment, including humans, needs to be further investigated. In this study, a new hybrid power unit is developed and equipped on a commercial electric bike. The energy performance of this prototype are analyzed together with its contribution to radiated electromagnetic emissions. The former analysis demonstrated the remarkable fuel efficiency shown by the new power unit, i.e., a 140km long distance can be covered at mean power, while the latter tests, undertaken within the reverberating chamber of the Universit`a degli Studi di Napoli “Parthenope”, demonstrated that the hydrogen bike prototype is compliant with the actual European Union regulations in terms of electromagnetic radiations, and that long-term effects of its radiations on humans are negligible

New national and regional Annex I Habitat records: From #45 to #59

New Italian data on the distribution of Annex I Habitats are reported in this contribution. Specifically, 8 new occurrences in Natura 2000 sites are presented and 27 new cells are added in the EEA 10 km × 10 km reference grid. The new data refer to the Italian administrative regions of Apulia, Campania, Calabria, Lazio, Tuscany, Umbria, Sardinia, and Sicily

Performance Of A Spark Ignition Engine Fuelled With Reformate Gas Produced On-Board Vehicle

In recent years, the interest in the use of hydrogen, as an alternative fuel for spark-ignition engines, has grown according to energy crises and pollution problems. By comparing the properties of hydrogen and gasoline, it is possible to underline the possibilities, for hydrogen–gasoline fuelled engines, of operating with very lean mixtures, thus obtaining interesting fuel economy and emission reductions. In this paper, the performance of a spark-ignition engine, fuelled by hydrogen enriched gasoline, has been evaluated by using a numerical model. A multidimensional code (KIVA-3V) has been modified in order to model the engine combustion process using a hybrid combustion model adapted for dual fuelling. Based on computed results, the performance of the engine has been evaluated in different operating conditions. Furthermore, for the hydrogen enriched gasoline engine fuelling, the hydrogen production on-board the vehicle has been considered. A thermochemical model of a reforming system has been developed by means of the Aspen Plus code. The conversion of gasoline to hydrogen has been investigated and thermodynamic analysis of the reforming system has been conducted. The thermal efficiency of the fuel processor and the efficiency of the integrated reformer/SI engine system have been calculated. 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved