DSpace Collection:http://hdl.handle.net/10174/52702024-03-29T11:15:55Z2024-03-29T11:15:55ZCarbon-Based Hybrid Supercapacitors for High Power Photovoltaic IrrigationHorta, MárciaFialho, LuísFoles, AnaHorta, Pedrohttp://hdl.handle.net/10174/357792023-12-12T14:24:21Z2023-11-30T00:00:00ZTitle: Carbon-Based Hybrid Supercapacitors for High Power Photovoltaic Irrigation
Authors: Horta, Márcia; Fialho, Luís; Foles, Ana; Horta, Pedro
Abstract: A photovoltaic pumping system comprises the following components: a solar photovoltaic (PV) installation, a variable frequency converter, a motor-pump, and a water source. The application combines solar PV technology, hydraulic engineering, and high-efficiency water management techniques to optimize irrigated farming. In the last decades, a growing trend has been observed in the application of renewable energies, which depend on the weather and daily conditions. In the case of cloud passing periods, the generation of energy by the photovoltaic system is drastically reduced, which will affect the overall general operation of the system. To better account for the considered operating parameters of a high-power PV pumping system, dedicated control algorithms have been developed in recent years [1], with the aim of mitigating solar power intermittency. One of the options that can be considered to avoid the sudden change in power generated by the solar PV system is to integrate an energy storage system that could accommodate those changes. In this way, carbon-based hybrid supercapacitors (HSupercap) represent the opportunity to solve this issue with a cost effective and long-lasting energy storage system, controlling PV power ramp rate, improving its overall lifetime. The HSupercap [2] was installed, configured, and tested to characterize it and assess this integration possibility. The tested system presented overall performance characteristics suitable for its application in high power photovoltaic pumping or irrigation.2023-11-30T00:00:00ZValidation of a lithium-ion commercial battery pack model using experimental data for stationary energy management applicationFoles, AnaFialho, LuisHorta, PedroCollares Pereira, Manuelhttp://hdl.handle.net/10174/353322023-07-17T13:53:32Z2022-02-03T00:00:00ZTitle: Validation of a lithium-ion commercial battery pack model using experimental data for stationary energy management application
Authors: Foles, Ana; Fialho, Luis; Horta, Pedro; Collares Pereira, Manuel
Abstract: Background: A cost-effective solution for the design of distributed energy storage systems implies the development of battery
performance models yielding a suitable representation of its dynamic behaviour under realistic operation conditions.
Methods: In this work, a lithium-ion battery (LIB) is tested to be further modelled and integrated into an existing energy management
control system. This specific LIB (5.0 kW /9.8 kWh) is integrated with a commercial inverter and solar photovoltaic (PV) system (3.3 kWp) as part of a microgrid that is also encompassing other energy storage technologies at the University of Évora, Pole of INIESC – National Research Infrastructure for Solar Energy Concentration. A testing
protocol fully characterizes the battery and the inverter efficiency to describe their performance better. Then, a battery model is built upon both the existent LIB description and experimental fitting regression.
The model allows obtaining the voltage curve, the internal resistance (i.e., to describe instantaneous voltage drop/rise and transients), and the state of charge (SOC) and/or energy capacity based on the current
input. The developed model is validated through the comparison with the experimental results.
Results: The model approach presented a higher voltage RMSE (root mean square error) of 5.51 V and an MRE (maximum relative error) of 5.68 % in the discharge state. Regarding SOC, the MRE obtained was approximately 6.82 %. In the charge state, the highest RMSE voltage was 5.27 V, with an MRE of 6.74 %. Concerning SOC, the MRE obtained was approximately 6.53 %.
Conclusions: The developed model is validated through the comparison with experimental results. Based on computational effort,
simplicity of use and the associated model error, the approach is validated to the regular conditions of the commercial battery pack to be incorporated in the next research step, following a bottom-upmodelling approach for an increasingly more complex smart grid.2022-02-03T00:00:00ZEconomic and energetic assessment of a hybrid vanadium redox flow and lithium-ion batteries, considering power sharing strategies impactFoles, AnaFialho, LuisHorta, PedroCollares Pereira, Manuelhttp://hdl.handle.net/10174/353312023-07-17T13:52:36Z2023-06-27T23:00:00ZTitle: Economic and energetic assessment of a hybrid vanadium redox flow and lithium-ion batteries, considering power sharing strategies impact
Authors: Foles, Ana; Fialho, Luis; Horta, Pedro; Collares Pereira, Manuel
Abstract: Hybrid energy storage systems (HESS) combine different energy storage technologies aiming at overall system performance and lifetime improvement compared to a single technology system. In this work, control combinations
for a vanadium redox flow battery (VRFB, 5/60 kW/kWh) and a lithium-ion battery (LIB, 3.3/9.8 kW/kWh) are investigated for the design of a HESS. A literature review presents the available energy management/
power allocation options that are being studied and applied worldwide in batteries. There is an identified need for opportunities to address better HESS configuration’s economic and energy perspective for building applications. The justification of investment in such HESS should improve indicators on use scenarios based on energy management compared to single-battery scenarios. In that context, four scenarios for real-time algorithms application approaches are considered to operate the hybrid storage solution through a 15-year economic and energetic analysis using experimentally validated battery performance models. The results obtained for each scenario are compared with a single technology battery performance to analyse this HESS pair competitiveness and the relevance of the power-sharing techniques among the different ESS technologies, which should be weighted. In the definition of the scenarios, real electricity generation is considered from two solar photovoltaic installations (3.2 kWp and 6.7 kWp) and an estimated representative load of a services building. HESS performance is evaluated through specific energy and economic key performance indicators. The results indicate that using customised energy management strategies (EMSs) renders the VRFB and LIB characteristics complementary, besides enhancing the competitiveness of VRFB as a single technology. Moreover, the HESS management impacts the seasonality factor, contributing to the overall electric system smart management.2023-06-27T23:00:00ZProjeto AMIGO na Promoção do Ensino Digital e Ensino em RedeGuerreiro, LuisMorais, ManuelaSuman, Danielhttp://hdl.handle.net/10174/352102023-05-19T18:11:22Z2022-10-12T23:00:00ZTitle: Projeto AMIGO na Promoção do Ensino Digital e Ensino em Rede
Authors: Guerreiro, Luis; Morais, Manuela; Suman, Daniel
Editors: Oosterbeek, Luis
Abstract: O AMIGO é um Consórcio criado em 2017 por iniciatica de 5 instituições de Ensino Superior que pertencem à rede de estudos ambientais de Países de Lingua Portuguesa (REALP). Nas
seus objectivos conta com a integração de diferentes linguagens e abordagens cientificas,
nomeadamente apoiando o Ensino digital, à distância e no fortalecimento de parcerias
entre instituições que em rede abraçam as tecnologias digitais como sejam a realidade
virtual, realidade aumentada e a criação de conteúdos Multimédia. Este é o caso da
cooperação entre a Universidade de Évora (Portugal) e a Universidade de Miami (EUA) nas áreas da Biodiversidade e Recursos marinhos, cuja cooperação se apoia no Ensino digital.2022-10-12T23:00:00Z