Combined production of electricity and hydrogen from solar energy and its use in the wine sector

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/In the present research, the energy demanded by the wastewater treatment plant of a winery and the pumping station of the irrigation system of a vineyard is supplied by a stand-alone renewable energy system formed by three photovoltaic arrays connected to a microgrid. A relatively small battery maintains the stability and quality of the energy supply acting as a short-term energy storage. Hydrogen is generated in a production and refueling plant specifically designed for this project, and it is eventually used in a plug-in BEV properly modified as a hybrid vehicle by adding a PEM fuel cell. On the one hand, the technical and economic feasibility of the on-site electricity production for the winery and vineyard, compared to the commercial electricity from the grid and diesel gensets, is demonstrated. On the other hand, the diesel savings by the hydrogen generated on site are assessed. The electricity (72 MWh) and hydrogen (1,214 m3) produced in the first year have saved the emission of around 27 tons of equivalent CO2.Peer ReviewedPostprint (author's final draft

Vanadium redox flow battery state of charge estimation using a concentration model and a sliding mode observer

Vanadium redox flow batteries are very promising technologies for large-scale, inter-seasonal energy storage. Tuning models from experimental data and estimating the state of charge is an important challenge for this type of devices. This work proposes a non-linear lumped parameter concentration model to describe the state of charge that differentiates the species concentrations in the different system components and allows to compute the effect of the most relevant over-potentials. Additionally, a scheme, based on the particle swarm global optimization methodology, to tune the model taking into account real experiments is proposed and validated. Finally, a novel state of charge estimation algorithm is proposed and validated. This algorithm uses a simplified version of previous models and a sliding mode control feedback law. All developments are analytically formulated and formally validated. Additionally, they have been experimentally validated in a home-made single vanadium redox flow battery cell. Proposed methods offer a constructive methodology to improve previous results in this field.Peer ReviewedPostprint (published version

Assessment of energy management in a fuel cell/battery hybrid vehicle

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksThe energy management strategy plays a major role in hybrid platforms powered by fuel cells (FCs) and batteries. This paper presents an assessment of energy management focused on fuel economy and battery degradation. Particularly, a proposed heuristic strategy and the widely known equivalent consumption minimization strategy are compared with the optimal solution obtained offline via dynamic programming. The case study is based on a real FC hybrid vehicle. Accordingly, the powertrain model of the vehicle used for the simulations is validated experimentally, and the profile of the power demand is measured from the real application. The results show that the proposed strategy offers the same performance as the equivalent consumption minimization strategy when the battery degradation is prioritized, and in comparison with the optimal off-line solution, it can be seen that there is still margin for improvement in terms of battery degradation.Peer ReviewedPostprint (published version

Combined production of electricity and hydrogen from solar energy and its use in the wine sector

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/In the present research, the energy demanded by the wastewater treatment plant of a winery and the pumping station of the irrigation system of a vineyard is supplied by a stand-alone renewable energy system formed by three photovoltaic arrays connected to a microgrid. A relatively small battery maintains the stability and quality of the energy supply acting as a short-term energy storage. Hydrogen is generated in a production and refueling plant specifically designed for this project, and it is eventually used in a plug-in BEV properly modified as a hybrid vehicle by adding a PEM fuel cell. On the one hand, the technical and economic feasibility of the on-site electricity production for the winery and vineyard, compared to the commercial electricity from the grid and diesel gensets, is demonstrated. On the other hand, the diesel savings by the hydrogen generated on site are assessed. The electricity (72 MWh) and hydrogen (1,214 m3) produced in the first year have saved the emission of around 27 tons of equivalent CO2.Peer Reviewe

Assessment of energy management in a fuel cell/battery hybrid vehicle

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksThe energy management strategy plays a major role in hybrid platforms powered by fuel cells (FCs) and batteries. This paper presents an assessment of energy management focused on fuel economy and battery degradation. Particularly, a proposed heuristic strategy and the widely known equivalent consumption minimization strategy are compared with the optimal solution obtained offline via dynamic programming. The case study is based on a real FC hybrid vehicle. Accordingly, the powertrain model of the vehicle used for the simulations is validated experimentally, and the profile of the power demand is measured from the real application. The results show that the proposed strategy offers the same performance as the equivalent consumption minimization strategy when the battery degradation is prioritized, and in comparison with the optimal off-line solution, it can be seen that there is still margin for improvement in terms of battery degradation.Peer Reviewe

The Winfrith horizontal impact rig

SIGLEAvailable from British Library Document Supply Centre- DSC:1769.7F(AEEW-M--2277)(microfiche) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

A virtual sensor for a cell voltage prediction of a Proton-Exchange Membranes based on intelligent techniques

The use of Proton-Exchange Membranes Fuel Cells is presented as a key alternative to face the increasing and concerning problems related to global warming. The international expansion of green policies, has resulted in the need of ensuring their quality and reliability performance. Although fuel cells can get to play a signicant role, this technology is still under development, paying special attention to the problems related to gas starvation and degradation. In this context, the present work deals with the virtual sensor implementation of one of the voltage cells present in a stack, whose operation is subjected to several degradation cycles. The proposal predicts indirectly the voltage of one cell from the current state of the rest of the cells by means of an intelligent model.Peer ReviewedPostprint (author's final draft

Optimal design and operational tests of a high-temperature PEM fuel cell for a combined heat and power unit

Development of new materials for polymer electrolyte membranes has allowed increasing the operational temperature of PEM fuel cell stacks above 120 degrees C. The present paper summarizes the main results obtained in a research devoted to the design, fabrication and operational tests performed on a high-temperature PEMFC prototype. A 5-cell stack has been assembled with commercial Celtec P-1000 high-temperature MEAs from BASF Fuel Cells, but the rest of elements and processes have been developed at LIFTEC research facilities. The stack includes different novelties, such as the way in which reactant gases are supplied to the flowfield, the design of the flowfield geometry for both anode and cathode plates, the concept of block that eases the assembling and maintenance processes, and the heating strategy for a very fast start-up. The different procedures comprising the assembly, closing and conditioning stages are also widely described and discussed. Results obtained in the preliminary operational tests performed are very promising, and it is expected that the 30-cells HT-PEMFC stack will deliver an electric power 2.3 times larger than the one initially predicted. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.Peer Reviewe