• Energy Research
• Embargo close
• ES close
• IT close

[EN] The objective of this article is to compare the behaviour of the most representative domestic hot water systems (DHW) in single-family buildings. The study evaluates the energy consumption, equivalent CO2 emissions and cost for each system over a 15-year life period. This analysis is carried out in four cli- matic zones across Europe to observe the influence of climatic conditions on the results. The four climatic zones are located in the cities of Athens, Madrid, London and Berlin. The analysed systems are: a) natural gas-fired instantaneous water heaters, b) electric storage water heater, c) solar thermal system with gas- fired instantaneous, d) solar thermal system with electric storage water heater, e) air-source heat pump, f) photovoltaic system with electric storage water heater, and g) photovoltaic system with air-source heat pump. This range of technologies covers the most likely solutions to be implemented across domestic buildings in Europe.The heat pump system (HPWH) with PV considering self-consumption shows the lowest environmen- tal impact in all zones, but is not an attractive investment in the coldest zones due to lower natural gas prices. Thermal solar systems have a high purchase and maintenance costs which do not compensate their energy savings. The PV HPWH system has a greater reduction of emissions and a lower cost than HPWH across a 15-year life. The gas boiler system has the lowest cost in a 15-year period in the coldest areas, despite having a greater environmental impact than the heat pump.(c) 2023 Elsevier B.V. All rights reserved.

Environmental tax reform (ETR), a shift from labour to carbon taxes, has been mostly modelled using general equilibrium (GE) analysis. Since a low-carbon transition will require deep transformations, one will also have to address out-of-equilibrium dynamics and increased agent heterogeneity. Unlike GE models, agent-based models (ABMs) are well equipped to deal with this. We therefore replicate a recent GE model for ETR using an agent-based approach. This process, known as "agentization", allows assessing similarities as well as differences in policy impacts between the two modelling approaches, in turn providing a test of the robustness of the GE results. We find that the agent-based model is able to replicate many results of the general equilibrium analysis, while revealing strengths and weaknesses of both model types. We discuss concrete implementation steps and difficulties experienced in the GE-ABM translation process. We illustrate the potential of ABM by extending the model in several directions. We show that heterogeneous subsistence consumption can increase the space for combining a double dividend with an equity goal, and that overall macro-economic results can conceal important distributional impacts when green preferences and labour supply elasticities vary.

Integrating environmental, social and governance (ESG) variables into the assessment of a mining project is essential to ensure the short and long term acceptance by the various stakeholders involved and the lack of doing so can put the sustainability of a project at risk. Thus, a holistic approach has been proposed which combines profitability and sustainability analysis with social and environmental considerations for any decisions made on processing operation selection or mine expansion. The potential economic implications of these factors would be used for determining the operational strategy. This study is based on an actual quarry case study and statistical data taken from Spain. Quantitative variables related to ESG aspects have been integrated into a block model, and optimisations were performed based on different plant types and waste disposal strategies. Results demonstrate a strong interdependence between profitability and sustainability. It is observed that strategies related to operating costs impact the environmental and social impacts. A green index is also incorporated to evaluate and compare the different scenarios, determining that the most relevant strategies in adding value to mining projects include investment in new technologies, environmental solutions, and economic and social benefits. Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura Objectius de Desenvolupament Sostenible::8 - Treball Decent i Creixement Econòmic Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables Peer Reviewed

Resumen: En este Trabajo de Final de Grado se aborda, como principal objetivo la reducción del consumo energético, en una bodega construida en el año 1965 con posteriores modificaciones para adaptarse a las demandas de la producción, en la actualidad tiene capacidad para procesa un máximo de 10 millones de kilos de uva por vendimia. Una de las modificaciones fue el cambio de ubicación de la zona de recepción del mosto, pasando de la cota más alta a la parte más baja de la finca, de unos depósitos de cemento a los de acero inoxidable i de estar ubicados en el interior de la bodega a la intemperie. Como se ha apuntado anteriormente, el principal objetivo de este proyecto es la reducción del consumo energético y concretamente de la zona de recepción, para tal fin se construirá un cofre aislante con las siguientes medidas 35 x 16 x 14 m, albergando en su interior los depósitos y el intercambiador de calor, ejecutándose la obra con dichos elementos inamovibles. Se han realizado los cálculos pertinentes para el dimensionado de la estructura metálica del cofre, de los cabales y dimensiones de los nuevos circuitos de refrigeración, calculando la potencia frigorífica necesaria para mantener la temperatura deseada, con una entrada máxima diaria de 200 tn de uva por día. Los cerramientos se realizarán con paneles aislantes que permitan mantener la temperatura del mosto refrigerado inicialmente hasta su clarificación y trasiego. Se ha calculado un presupuesto de ejecución de obra por contrato y se han elaborado los planos correspondientes. Así pues el proyecto consta de los siguientes documentos: Documento N.º 1 Memoria y 9 Anejos Documento N.º 2 Planos Documento N.º 4 Presupuesto detallado Como conclusión, podemos afirmar que con este proyecto se espera una reducción del 55% en el consumo energético de la zona de Recepción del mosto, mejoraría el rendimiento, tanto energético como en eficiencia con la automatización de las instalaciones entre la zona de Recepción y el Lagar. Abstract: This Final Degree Work addresses the reduction of energy consumption, mainly electricity, of a winery built in 1965, with subsequent modifications adapting to production circumstances, with the capacity to process 10 million kilos of grapes. One of the modifications was the change in location of the must reception area, moving from the highest to the lowest level of the farm, from cement tanks to stainless steel tanks and to be located inside the cellar in the open air. The objective of the project is the reduction of energy consumption in the must reception area, through the construction of an insulating box of 35 x 16 x 14 m, closing the six tanks and the tubular heat exchanger inside. the work being carried out with said immovable elements inside. The necessary calculations have been made for the dimensioning of the metal structure of the chest, the flow rates and the dimensions of the new refrigeration circuits, as well as the refrigeration power necessary to maintain them at the desired temperature, with a daily input of 200 t of grape The enclosures will be made with insulating panels that allow the temperature of the initially cooled must to be maintained until its clarification by gravity. A contract execution budget has been calculated and the corresponding plans have been drawn up. So, the project consists of the following documents: Document Nº1: Memory and 9 chapters. Document No. 2: 19 plans Document Nº4: Detailed budget. As a conclusion we will say that this project is expected to reduce energy consumption in the reception area by 55% and we can affirm that the performance, both energy and efficiency, would improve if the facilities between the Reception area and the Presses. Resum: En aquest treball de Final de Grau s'aborda la reducció del consum energètic d'un celler construït l'any 1965, amb posteriors modificacions per adaptar-se a les circumstancies de la producció, amb capacitat per processar 10 milions de quilos de raïm . Una d'elles va ser el canvi d'ubicació de la zona de recepció del most, passant de la cota mes alta a la part mes baixa de la finca, d'uns dipòsits de ciment a uns d'acer inoxidable i d'estar en el interior del celler al intempèrie. L'objectiu del projecte serà doncs, la reducció del consum energètic de la zona de recepció del most, mitjançant la construcció d'un cofre aïllant de 35 x 16 x 14 m, tancant en el seu interior els dipòsits i l'intercanviador de calor que romandran en el seu lloc mentre s'executi el projecte. S'han realitzat els càlculs necessaris per dimensionar l'estructura metàl·lica del cofre, dels cabals i dimensions dels nous circuits de refrigeració i de la potencia frigorífica necessària per mantenir-los, amb una entrada màxima diària de 200 tn de raïm per dia. Els tancaments es realitzaran amb panells aïllants que permetin mantenir la temperatura del most refredat inicialment, fins al seu desfangat estàtic. S'ha calculat un pressupost d'execució d'obra per contracta i s'han elaborat els plànols corresponents. Així doncs, el projecte consta del: Document Nº 1: Memòria i 9 Annexes. Document Nº 2: 19 plànols Document Nº 4: Pressupost detallat Com a conclusió direm que d'aquest projecte s'espera una reducció del 55% en el consum energètic a la zona de recepció del most i que es milloraria el rendiment, tant energètic com en eficiència amb l'automatització de les instal·lacions entre la Recepció i el Lagar. Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables

Abstract As main contributors to greenhouse gas emissions, power and transportation are crucial sectors for energy system decarbonization. Their interaction is expected to increase significantly: plug-in electric vehicles add a new electric load, increasing grid demand and potentially requiring substantial grid upgrade; hydrogen production for fuel cell electric vehicles or for clean fuels synthesis could exploit the projected massive power overgeneration by intermittent and seasonally-dependent renewable sources via Power-to-Hydrogen. This work investigates the infrastructural needs involved with a broad diffusion of clean mobility, adopting a sector integration perspective at the national scale. The analysis combines a multi-node energy system balance simulation and a techno-economic assessment of the infrastructure to deliver energy vectors for mobility. The article explores the long-term case of Italy, considering a massive increase of renewable power generation capacity and investigating different mobility scenarios, where low-emission vehicles account for 50% of the stock. First, the model solves the energy balances, integrating the consumption related to mobility energy vectors and taking into account power grid constraints. Then, an optimal infrastructure is identified, composed of both a hydrogen delivery network and a widespread installation of charging points. Results show that the infrastructural requirements bring about investment costs in the range of 43–63 G€. Lower specific costs are associated with the exclusive presence of FCEVs, whereas the full reliance on BEVs leads to the most significant costs. Scenarios that combine FCEVs and BEVs lie in between, suggesting that the overall power + mobility system benefits from the presence of both drivetrain options.

The optical and photovoltaic properties of Si NCs / SiC multilayers (MLs) are investigated using a membrane-based solar cell structure. By removing the Si substrate in the active cell area, the MLs are studied without any bulk Si substrate contribution. The occurrence is confirmed by scanning electron microscopy and light-beam induced current mapping . Optical characterization combined with simulations allows us to determine the absorption within the ML absorber layer, isolated from the other cell stack layers. The results indicate that the absorption at wavelengths longer than 800 nm is only due to the SiC matrix. The measured short-circuit current is significantly lower than that theoretically obtained from absorption within the ML absorber, which is ascribed to losses that limit carrier extraction. The origin of these losses is discussed in terms of the material regions where recombination takes place. Our results indicate that carrier extraction is most efficient from the Si NCs themselves, whereas recombination is strongest in SiC and residual a-Si domains . Together with the observed onset of the external quantum efficiency (EQE) at 700-800 nm, this fact is an evidence of quantum confinement in Si NCs embedded in SiC on device level.