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- ItemOpen AccessApplication of deep learning techniques to minimize the cost of operation of a hybrid solar-biomass system in a multi-family building(Elsevier, 2023) Zsembinszki, Gabriel; Fernàndez Camon, César; Borri, Emiliano; Cabeza, Luisa F.Concerns related to climate change put renewable energy at the centre of most of the policies aimed at achieving a deep decarbonisation of the building sector. The combined use of two or more renewable energy sources in the same energy system can lead to an increase in the total share of renewable energy and in the flexibility of the system. In this direction, the SolBio-Rev project aims to develop an innovative system that uses solar thermal collectors and a biomass boiler to meet energy demand in buildings in different climatic regions. An advanced control that used deep reinforcement learning techniques was considered in this paper to find an optimal control strategy for a specific SolBio-Rev system installed in a standard multi-family residential building located in Madrid. The advanced control was developed to minimize the total cost of operation of the system. The results indicated that the advanced control strategy achieved a cost reduction of 35% in winter, compared to a standard rule-based control strategy. However, the improved control was not able to produce a significant cost reduction in summer.
- ItemOpen AccessEurotherm Seminar #116 “Innovative solutions for thermal energy storage deployment”(Edicions i Publicacions de la Universitat de Lleida, 2023-05) Cabeza, Luisa F.; Ziskind, Gennady; De Paepe, Michel; Zsembinszki, Gabriel; Borri, Emiliano; Vérez, David; Martínez Alcocer, F. Rodrigo; Rojas, Eduard; Mehraj, Nadiya; Ribezzo, Alessandro; Rehman, Omais Abdur; Tagle Salazar, PabloEurotherm Seminar #116 brings together researchers and practitioners from academia and industry, who are working in the rapidly expanding field of thermal energy storage (TES). The seminar aims to cover most recent trends in such areas as novel storage materials, advanced storage concepts and configurations, TES for renewable energy systems, TES in buildings and industry, use of advanced techniques such as artificial intelligence in TES, and social, environmental, and educational aspects.
- ItemEmbargoStandardised methods for the determination of key performance indicators for thermal energy storage heat exchangers(Elsevier, 2023) Beyne, Wim; T'Jollyn, Ilya; Lecompte, Steven; Cabeza, Luisa F.; De Paepe, MichelLatent thermal energy storage (LTES) heat exchangers can provide energy storage in a broad range of energy systems. Implementing LTES heat exchangers requires an assessment of their performance in a given system. The performance of a LTES heat exchanger is described by its performance indicators which are classified as technical, economical, and life-cycle indicators. The current paper focusses on the technical performance indicator and specifically on predictive methods which aid the assessment of the performance of a LTES heat exchanger in a system. To structure the analysis, a thermodynamic framework is provided which allows to clearly define LTES heat exchangers and classify the technical performance indicators. In a second step, the literature is reviewed for reported technical performance indicators with a specific focus on predictive methods for these indicators. The averaged effectiveness-number of transfer units (ε-NTU) and phase change time method are identified as important predictive models, analyzed, and compared based on their theoretical derivation. The relation between the averaged effectiveness and phase change time is investigated both theoretically and based on data available in literature which results in recommendations for standardizing the characterization of LTES heat exchangers. By standardizing characterization of LTES heat exchangers, researcher can assess their performance in different energy systems without additional experiments or CFD calculations.
- ItemOpen AccessEnergy Assessment of a Tannery to Improve Its Sustainability(MDPI, 2023) Morera Prat, Josep M.; Borri, Emiliano; Zsembinszki, Gabriel; Vérez, David; Gasa, Gemma; Bartolí, Esther; Cabeza, Luisa F.The tanning industry is one of the highly polluting sectors, and it is only in the last few years that studies on the energy improvement of tanneries started to proliferate in the literature. Even though the energy cost of a tannery is only a small fraction of the total cost, many tanners became aware of the importance of improving energy efficiency and reducing the environmental footprint to keep the business afloat and be more competitive in the market. This paper presents a study on increasing the sustainability of a tannery located in the region of Catalonia, Spain. Several measures to increase its energy efficiency and reduce its primary energy consumption were proposed and analysed including, among others, the implementation of solar thermal collectors and photovoltaic panels. A cost analysis of the most promising solutions was carried out and discussed. The results show that the tannery should invest between EUR 2 to 2.5 M to obtain the highest energy savings, with an estimated payback period between 5 and 7 years. However, acceptable energy savings can be obtained with a lower investment cost of between EUR 1 to 1.5 M, with a shorter payback period of between 2 and 4 years.
- ItemOpen AccessNumerical and Experimental Analysis of a Low-GWP Heat Pump Coupled to Electrical and Thermal Energy Storage to Increase the Share of Renewables across Europe(MDPI, 2023) Rehman, Omais Abdur; Palomba, Valeria; Frazzica, Andrea; Charalampidis, Antonios; Karellas, Sotirios; Cabeza, Luisa F.In order to reduce the dependence on fossil fuels in the residential sector, low-carbon-footprint technologies such as heat pumps should be used. To fully exploit solar-assisted heat pumps, an effective control strategy is required. This study employs a low-global-warming-potential (GWP) refrigerant for a water-to-water reversible heat pump, which is assisted by a thermal energy storage tank, photovoltaic (PV) installation, and battery storage system using a dedicated control strategy. The heat pump’s operation is validated against the experimental data. Simulations are carried out for three different climates to analyze the performance of reversible heat pumps across Europe. The reversible heat pump fully meets the summer cooling demand in all three climates, while the heating demand is covered with the help of a backup source. An economic analysis is carried out for three different PV sizes and the results are compared with the reference energy systems. The inclusion of a battery storage system results in high payback times but increases overall flexibility and self-sufficiency.
- ItemOpen AccessRecycling Textile Waste to Enhance Building Thermal Insulation and Reduce Carbon Emissions: Experimentation and Model-Based Dynamic Assessment(MDPI, 2023) Ayed, Rabeb; Bouadila, Salwa; Skouri, Safa; Boquera, Laura; Cabeza, Luisa F.; Lazaar, MariemBy enhancing the thermal properties of cement-based building materials, energy consumption and carbon dioxide (CO2) emissions related to space conditioning in buildings can be alleviated. This study aims to present cement-based composites reinforced by textile fibers for application in building and construction. Several lightweight coating mortars were produced by partially replacing the sand in the mix with different percentages of textile waste. Mechanical and thermal characterizations of the reinforced cementitious composites were performed. The results showed that the thermal conductivity of cementitious compounds decreased as the proportion of reinforcing material in the mixture increased. In terms of mechanical properties, the textile slightly reduced the compressive strength of cementitious mortar, while it improved the flexural strength. A numerical study was then performed to derive the actual impact of these reinforced materials on the thermal behavior of a building element using COMSOL Multiphysics. Numerous configurations of walls coated with different mortar mixtures were studied. The results showed that coating both sides of a building wall with 20 mm of textile-reinforced mortar reduced the internal temperature by 1.5 ◦C. Thus, the application of these thermally improved mortars as coating mortars appears to be a relevant solution to enhance the thermal performance of buildings.
- ItemOpen AccessClúster porcino en Placetas: oportunidades, particularidades e impactos en el desarrollo de la localidad(Universo Sur, 2022) Pérez Navarro, Omar; Concepción Toledo, Diana N.; Cabeza, Luisa F.; Ramírez González, José; Cruz Montesinos, OmaidaLa influencia de la globalización mundial, incide directamente en la forma en que las instituciones, empresas y gobiernos diseñan, pla-nifican y ejercen sus actividades, teniendo en común, la imposibilidad de concebir acciones de forma aislada, si no, en estrecho vínculo con los actores que contribuyen al logro de sus fines. El desarrollo de la actividad agropecuaria, y dentro de ella, la producción porcina, no escapa a esta realidad. Resulta necesario realizar transformaciones en las formas de organización económica, insertar los avances tecnológicos en sus procesos y elaborar estrategias para adecuarse a los retos de producción que satisfaga las demandas del mercado. El objetivo del estudio consiste en argumentar las oportunidades, particularidades y posibles impactos que puede generar la formación de un clúster porcino en el municipio Placetas para elevar la producción porcina, ajustado a las características de esta localidad y contan-do con la cooperación entre los actores implicados. Se abordan los fundamentos teóricos del clúster como modalidad de cooperación, sus características esenciales y las ventajas de su aplicación. Adicionalmente, se valoran los desafíos y la posibilidad de insertar en la práctica, resultados de la actividad científica e innovativa, para el logro de este propósito y se comentan los impactos que en el orden económico, social y ambiental pudiera reportar. Se concluyó que la estrategia de creación de un clúster porcino puede ser considerada una vía para elevar la producción, fomentar la colaboración conjunta entre la universidad, el entramado empresarial y los gobiernos, cuyos resultados redunden en el beneficio del desarrollo local.
- ItemOpen AccessPneumatic Urban Waste Collection Systems: A Review(MDPI, 2023) Farré, Josep Anton; Mateu Piñol, Carles; Teixidó Cairol, Mercè; Cabeza, Luisa F.Due to the increasing need for a more sustainable environment, the study of waste management strategies is increasing worldwide. Pneumatic urban waste collection is an alternative to conventional truck collection, especially in urban areas where there is a need for reducing traffic and pollution. In this study, the scientific literature on such automated waste collection systems (AWCSs) (also known as automated vacuum waste collection (AVWC) systems) is evaluated through a bibliometric analysis. The available scientific literature is found to be scarce, while there are several patents on the topic. The keywords used in the literature are mainly related to energy use, gas emissions, and the cost-benefit analysis. Moreover, the market status is presented and a summary of the environmental studies is provided. The active companies in the field are identified and a complete list of AWCSs is provided. Most of the scientific literature related to the environmental aspects of AWCSs uses the life cycle assessment (LCA) methodology to evaluate the performance of different case studies.
- ItemEmbargoTechno-economic analysis of a concrete storage concept for parabolic trough solar power plants(Elsevier, 2023) Prieto, Cristina; Pino, Francisco Javier; Cabeza, Luisa F.In an energy transition towards 100 % renewable electricity, concentrating solar power (CSP) with thermal energy storage (TES) should be deployed on a wide scale due to the dispatchability capacity of this technology. To achieve this, a decrease of its levelized cost of electricity (LCOE) is essential. This paper evaluates the technoeconomic potential of a CSP plant with high temperature concrete as TES system compared to the standard commercial molten salts system. The general plant design includes creating a bank of metal tubes enclosed by concrete in a modular configuration, aiming to maximize the performance of the plant (e.g., reducing parasitics). Nevertheless, the results proved that the selected configuration underperforms during the discharge phase in nominal conditions. Despite existing expectations, this study shows the prevalence of the current molten salt TES system as a better solution over the high temperature optimized concrete configuration studied.
- ItemOpen AccessThermal energy storage co-benefits in building applications transferred from a renewable energy perspective(Elsevier, 2023) Vérez, David; Borri, Emiliano; Zsembinszki, Gabriel; Cabeza, Luisa F.Although one of the main aims of using renewable energy sources in building applications is to reduce the environmental impact caused by the high global energy demand of buildings, it can also produce other positive effects, known as co-benefits. Thermal energy storage technologies are often used in building applications, either integrated into the renewable system or independently, for energy savings or energy efficiency reasons. This paper demonstrates that it is possible to identify the co-benefits of the use of thermal energy storage in buildings by cross-sectorizing the renewable energy and thermal energy storage sectors. To this end, this article first reviews the literature on the co-benefits of renewable energy for building applications, followed by an evaluation on how these co-benefits can be attributed to thermal energy storage in buildings. As a result of a keywords analysis, the main co-benefits of thermal energy storage were identified related to environmental, health, economic, cost, and policies aspects.