Gestión e integración de recursos energéticos naturales en edificios residenciales

La mejora de la eficiencia energética de los edificios, así como la gestión e integración de recursos energéticos naturales para el acondicionamiento de espacios, resulta indispensable para lograr el objetivo de la Unión Europea de alcanzar la neutralidad en emisiones de carbono y la lucha contra el cambio climático. La presente tesis doctoral desarrolla su trabajo en dicha línea de investigación. En el marco de la misma, se han estudiado tecnologías convencionales e innovadoras de producción eléctrica y térmica. Esto ha permitido concluir el fuerte potencial de implantación que está teniendo y tendrán las soluciones fotovoltaicas con o sin almacenamiento eléctrico, el acoplamiento de estas soluciones a bombas de calor y el uso del edificio o sus elementos como sistemas de almacenamiento térmico. Se destaca la novedad vinculada a la integración de sumideros medioambientales de calor para el enfriamiento de elementos estructurales del edificio y, sobre todo, para la producción de agua fría. La presente tesis doctoral destaca la posibilidad de la unión de las soluciones fotovoltaicas con la disipación natural del tipo “falling-film”, lo cual permite ofrecer una solución multipropósito, con un sobrecoste admisible y con una alta facilidad de integración en los edificios. Además, el agua fría producida durante las horas nocturnas puede ser integrable en la disipación de una bomba de calor, en el sistema de ventilación del edificio, o incluso usar la misma para enfriar la masa térmica del edificio (sistemas térmicamente activos TABS). Todo ello con objetivo de lograr un acondicionamiento natural de espacios y destacando de los resultados obtenidos la posibilidad de convertir a los edificios residenciales en edificios totalmente pasivos mediante la integración de las técnicas de enfriamiento natural estudiadas en la tesis doctoral

Sistema de gestión energética para edificios EMS siguiendo hoja de ruta BS-ISO 50006:2014

El presente proyecto final de máster tiene como objetivo proporcionar un método para la obtención de líneas base del consumo de edificios. Este método a diferencia del material publicado y existente, tiene dos grandes aportaciones: - Es una combinación de un algoritmo de clustering con una metodología de caracterización inversa de edificio, lo que combina una capacidad de extrapolación a diferentes condiciones climáticas y operación del edificio. Este aporte, a diferencia de los resultados que aparecen publicados, garantiza calidad de resultaos en periodos de explotación diferentes a los de referencia. De esta manera se ofrece más robustez a un método de verificación de ahorros o diagnóstico de errores a largo plazo - Posibilidad de automatizarlo y explotarlo en software para gestión energética o verificación de ahorros Por tanto el Trabajo que aquí se presenta, vinculado con las normas UNE-EN 50001 y BS ISO 50006, da solución al elemento clave que da sentido a ambas: obtención de línea base y referencias de consumo. A lo largo del documento, además de explicar el propio algoritmo y sus fundamentos, se exponen ejemplos de 6 edificios tipo gran terciario con usos de oficina, judiciales, y sanitarias. En todos ellos los resultados en el periodo de referencia y en el periodo de validación son aceptables y de alta eficiencia.Universidad de Sevilla. Máster Universitario en Sistemas de Energía Térmic

Sensitivity analysys and potential evaluation using building thermal mass combined with DSM strategies

CLIMA 2019 Congress. Bucharest, Romania, May 26-29, 2019. S.I Tanabe, H. Zhang, J. Kurnitski, M.C. Gameiro da Silva, I. Nastase, P. Wargocki, G. Cao, L. Mazzarela and C. Inard (Eds.)The objective of the work is to develop an algorithm that automatically manages the activation of the heat pump in response to the most appropriate strategies according to the pricing and operating conditions. It is interesting to see if a balance can be reached between the cost savings, the increase in energy consumed, the thermal comfort of the occupants and the contribution to the reduction of the peak loads. The study shows different results and conclusions, highlighting the important influence of various factors on the results obtained, such as user behavior, constructive quality of the building and electric pricing. Connection with a future renewable production can maximize the economic savings; it is interesting the use of buildings as thermal storage of unused photovoltaic surplus. Finally, the possibility of combining these measures with electrical storage and with the possible arbitration linked to renewable production.Ministry of Economy and Competitiveness (Government of Spain) and European Regional Development's funds (ERDF) project “Zero-Energy Balance Districts Through Algorithms of Adaptive Comfort and Optimal Management of Energy Networks” (BIA2016-77431-C2-2-R)University of Seville (Spain) Plan VI (VPPI-US

Experimental analysis of atmospheric heat sinks as heat dissipators

Artículo premiado ETSI 1er trimestre 2020Overheating, a general problem both in urban spaces and inside buildings, calls for the deployment of passive cooling techniques to reduce energy consumption, protect the environment and institute satisfactory comfort levels. A key factor in such techniques is the capitalisation on the cooling potential of natural heat sinks. The sky, one such sink, has essentially limitless cooling power. In addition, its temperature on fair nights is lower than that of other environmental sinks (ground and air). The sky's promise in that respect prompted this exploration of the potential of nocturnal radiation cooling. A review of the state of the art revealed that in all the radiative dissipators developed and tested to date the dissipation fluid (water) transferred heat indirectly to the heat sink (the sky) by circulating water inside solar collector pipes. The highest values reported for maximum dissipation power were on the order of 100 W/m2. The present study aimed to asses night time dissipation power in a dual system in which water circulated either inside pipes or flowed down the outer surface of the collector. The two modes, one involving in-pipe circulation and the other outer surface downflow, were compared experimentally, for whereas the former has been analysed and assessed by earlier researchers, the latter has not. The empirical findings verified that downflow setups enhanced cooling, delivering up to five-fold the dissipation power obtained with the conventional arrangement.Ministerio de Economía y Competitividad BIA2016-77431-C2-2-RFondos FEDER UIA03-30

Mitigating energy poverty: Potential contributions of combining PV and building thermal mass storage in low-income households

The issue of energy poverty has devastating implications for the society, and it has been aggravated in the past years due to the economic crisis and the increase of energy prices. Among the most affected are those with low incomes and living in inefficient buildings. Unfortunately, the bitter reality is that sometimes this part of the population are facing the next question: Heating, or eating? The declining prices of distributed energy technologies such as photovoltaics provides an opportunity for positive social change. Although their use does not address energy poverty directly, substantial contributions may be made. Measurements of indoor temperatures in a social housing district of southern Spain in 2017 have revealed the unbearable temperatures that the occupants have to endure, both in summer and winter. Using this district as a case study, the present work aims to evaluate the benefits of exploiting its rooftop PV potential to cover part of the electricity consumption of the district (reducing the energy bills), and use the surplus electricity to supply power for the heat pumps in the district. Optimal alternatives regarding maximum PV production, maximum self-sufficiency ratio and minimum investment costs have been found, considering as well different options when sharing the available electricity surplus to improve the thermal comfort of the occupants. As far as the authors know, no previous study has followed an approach aimed at energy poverty alleviation such as the one presented in this work. The results show that using the surplus electricity to heat or cool the whole dwellings would improve the thermal comfort of the occupants in average up to 11% in winter and 26% in summer. If all the PV generation was used or more buildings in the area were employed to install PV modules, improvements up to 33% in winter and 67% in summer could be obtained, reducing at the same time the thermal comfort differences among the dwellings of the district

CartujaQanat: Recovering the street life in a climate changing world. Bioclimatic lattices and confinement of air in exterior conditions

Article number 03205

Evaluation of the behavior of an innovative thermally activated building system (TABS) with PCM for an efficient design

The global energy crisis has caused a double effect. On the one hand, users are increasingly aware of the energy cost they face. On the other hand, public administrations have become aware of the importance of limiting energy consumption in buildings as a way to combat climate change and reduce the energy dependence with the climate. This situation supposes a great opportunity for innovative constructive solutions with an energetic behaviour that surpasses the traditional approach of reduction of the transmittance. In this work, studies are presented to obtain potential of a new solution thermally activated with two innovations with respect to those existing in the market: its activation is done by hot / cold water produced by renewable systems; and its concrete structural element in addition to having coupled the heat exchanger presents an innovative mortar doped with PCM microencapsulated phase change material.Ministry of Economy and Competitiveness (Government of Spain) and European Regional Development's funds (ERDF) project “Zero-Energy Balance Districts Through Algorithms of Adaptive Comfort and Optimal Management of Energy Networks” (BIA2016-77431-C2-2-R)University of Seville (Spain) Plan VI (VPPI-US

“Education Network” a new way to teach Chemistry

The complexity of chemistry has implications for the teaching of chemistry. That chemistry is a very complex subject. The majority of the students at University think that chemistry is a difficult discipline and they have difficulty in understanding the concepts. Moreover, students' interest in chemistry decreases the first year at university. The reason for this decrease might be that the contents of chemistry laboratory classes are boring, out of date and lacking of dynamism that students experience through visual media tools. For these reasons, new programs and methodologies should be developed. Those are based on making chemistry relevant through problem solving and collaborative learning hold promise for reforming chemistry education. It is about an education according to circumstances, which is adapted to context and virtual behaviour of people. It's time to CRUSH boredom by transforming your classroom into an Escape Room adventure. School-based escape games are a great teaching tool. The students while playing, learn. The most important point is that they won’t realize they’re doing both at the same time. In this work, an educational gamification experience based on the escape room concept was developed. The first (Do It Yourself) DIY Escape Room was built the year before at Mechanical Engineer Degree started, that took more than three weeks of work. It was presented to other professors to the same subject at different degrees. That DIY Escape Room was modified and adapted to each group. Each professor changed the clues, problems and so on in order to orientate the topic as much as possible to their students.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Evaporative Mist Cooling as Heat Dissipation Technique: Experimental Assessment and Modelling

The severity of extreme weather conditions brought on by climate change are conditioning quality of life, economic development, and well-being in today’s cities. Conventional measures have been shown to be insu cient for tackling climate change and must be supplemented with ecofriendly approaches. Hence, the scientific community’s endeavor to develop natural cooling techniques that lower energy consumption while delivering satisfactory comfort levels. For its simplicity and low cost, evaporative cooling has gained in popularity in recent years. The substantial cooling power to be drawn from evaporative mist cooling, makes it an attractive alternative to conventional systems. Research conducted to date on the technique has focused on producing cold air, whilst cooling the water involved has been neither assessed nor experimentally validated. No readily applicable simplified model for the system able to use operating parameters as input variables has been defined either. The present study consequently aimed to experimentally assess the cooling power of the evaporation of sprayed water and experimentally validate a simplified model to assess and design such systems. The findings confirmed the cooling power of the technique, with declines in water temperature of up to 6 C, and with it the promise a orded by this natural air conditioning method. Finally, simplified model developed allows to evaluate this technique like a conventional system for producing fresh water.Urban Innovation Actions by the CartujaQanat UIA03-30

Fresnel solar cooling plant for buildings: Optimal operation of an absorption chiller through inverse modelling

Increasing comfort conditions in buildings imply higher energy demands. However, these needs can be mitigated by solar cooling solutions. These systems, such as absorption chillers, are complex and require stable operation, with strict control to maximise the solar fraction and minimise gas consumption. This is incompatible with the variability of renewable resources, so they are often coupled with auxiliary gas systems. Although gas-free operation is possible if these systems are optimally controlled, they would require special supervision. This paper aims to develop an experimental validation of an inverse model to manage an absorption chiller coupled with a solar cooling plant. To know its real behaviour, long-term experiments have been performed using this plant, which consists of a linear Fresnel solar collector and an auxiliary natural gas boiler. The inverse model is used as a predictive control tool to decide the auxiliary boiler commands of the absorption chiller to optimise its operation: maximum cooling production by minimising gas consumption and maximising solar contribution. It has been identified with data from two weeks and validated with data from one summer month. Results show that the model estimates, on a time base of fewer than 30 min, are acceptable with errors of less than 5%. In addition, the maximum error of the estimated seasonal COP and the renewable fraction are less than 6% per day. Therefore, the results prove the usefulness of the proposal as a predictive control for optimal operation. Furthermore, it could be used as a baseline for preventive maintenance. If the proposed model is used for optimal management of the absorption chiller, the thermal efficiency of the plant increases significantly, doubling the solar contribution. As a result, the gas consumption of the solar cooling plant is halved and the total cost of air conditioning the building decreases by 16%.Comisión Europea A_B.4.3_02