Browsing by Author "Rubio-Bellido, Carlos"
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- Automation and optimization of in-situ assessment of wall thermal transmittance using a Random Forest algorithmPublication . Bienvenido-Huertas, David; Rubio-Bellido, Carlos; Luis Perez-Ordonez, Juan; Oliveira, M. J.Reducing energy consumption and greenhouse gases emissions is among the main challenges of building sector. It is therefore crucial to know the characteristics of envelopes. There are experimental methods to determine thermal transmittance, but limitations are presented. By using techniques of artificial intelligence, this article solves the limitations of current methods by predicting correctly the thermal transmittance value of ISO 6946 and the building period of a wall with monitored data. The methodology used is extrapolated to any country: 163 real monitorings and 140 different typologies of walls have been combined to generate the dataset (22,820 items). The results show the optimal operation of the Random Forest algorithm because both the thermal transmittance of ISO 6946 and the building period are determined by using the most common methods: the heat flow meter method and the thermometric method. This study makes progress towards more automatized processes to characterize thermal transmittance.
- A comparative analysis of the international regulation of thermal properties in building envelopePublication . Bienvenido-Huertas, David; Oliveira, Miguel; Rubio-Bellido, Carlos; Marín, DavidTo achieve the goals of reducing building energy consumption, regulations are being designed to guarantee the appropriate energy performance of buildings. Both European and South American countries establish requirements of thermal properties of building envelope according to the climate zone, thus implying notable differences in climate classifications and technical requirements. This research provides a general view of advantages and limitations between the different state regulations of three South American countries (Argentina, Brazil, and Chile) and three European countries (Spain, Portugal, and France). A total of 792 simulations were conducted with Energy Plus by considering 12 different dwelling typologies in 66 climate zones. Building envelopes were adapted to the regulations of the various countries. Results showed tendencies of performance clearly different between the South American and the European countries, with the latter being those with the lowest energy demands. The cluster analysis of distributions of energy demand revealed that buildings located in similar climates but in different countries present very different energy performances. This research opens up the discussion on the development of more demanding policies related to thermal properties of buildings. Also, the analysis at a continental scale could reduce the differences between countries and guarantee a more sustainable life for the building stock.
- Evaluating the potential of adaptive comfort approach using historic data to reduce energy consumption in buildings in southern SpainPublication . Bienvenido-Huertas, David; Rubio-Bellido, Carlos; Farinha, Fátima; Oliveira, Miguel José; Pérez-Ordóñez, Juan LuisThe application of adaptive comfort models is among the determinant factors to reduce greenhouse gas emissions in the building sector. This research studies the region of Andalusia (south of Spain). A cluster analysis is applied to 786 Andalusian municipalities, and 4 groups are established according to the potential of adaptive strategies. A town is chosen from each group, and an hourly specific study is conducted for the last 20 years, as well as a daily study of the old time series by using an artificial neural network based on the existing climate data. The possibility of application of the EN 16798-1:2019 standard during the days of the year is analysed, as well as the possibilities of using natural ventilation and the possibility of using adaptive setpoint temperatures in comparison with both 3 fixed heating temperatures and 3 fixed cooling temperatures by considering the energy saving. The results to apply the standard ranged 69.0 and 100% of the days of each year. The possibilities of natural ventilation considered were greater than 10% of the hours of the year in all the assumptions. The energy saving of cooling degrees reveals a greater potential in the area studied than that of heating degrees; this tendency is supported by the study of old temporary series which are part of the climate variation predicted throughout the 21st century.
- Experimental characterisation of the periodic thermal properties of walls using artificial intelligencePublication . Bienvenido-Huertas, David; Rubio-Bellido, Carlos; Solis-Guzman, Jaime; Oliveira, Miguel JoséThe energy performance of a building is affected by the periodic thermal properties of the walls, and reliable methods of characterising these are therefore required. However, the methods that are currently available involve theoretical calculations that make it difficult to assess the condition of existing walls. In this study, the characterisation of the periodic thermal variables of walls using experimental measurements and methods as described in ISO 13786 was assessed. Two regression algorithms (multilayer perceptron [MLP] and random forest [RF]) and input variables obtained using two experimental methods (the heat flow meter and the thermometric method) were used. The methods gave accurate estimates, and better statistical parameter values were given by the RF models than the multilayer perceptron models. For all the periodic thermal variables, the percentage differences between the actual values and the estimated values given by the RF algorithm were low. The heat flow meter and the thermometric methods can both be used to characterise accurately the periodic thermal properties of walls using the RF algorithm. The variables specific to each method, including the wall thickness and the date of construction, affected the accuracies of the models most strongly. (C) 2020 Elsevier Ltd. All rights reserved.
- Influence of adaptive energy saving techniques on office buildings located in cities of the Iberian PeninsulaPublication . Bienvenido-Huertas, David; Sanchez-Garcia, Daniel; Rubio-Bellido, Carlos; Oliveira, M. JoséThe use of setpoint temperatures based on adaptive comfort algorithms is a method more and more used as an energy saving technique. Knowing the relationship between inhabitable rooms with their specific climate is crucial for users' climate adaptation, especially in a global warming context. This research analyses the influence of EN 15251:2007, EN 16798-1:2019, and ASHRAE 55-2017 standards on an office building located in 65 cities. The effects of climate change have been considered in the energy performance of current, 2050, and 2100 scenarios. Also, 780 dynamic simulations were performed so that a cluster analysis was carried out to determine the similarity relationships among the various zones. The results show that the model of the EN 16798-1:2019 standard was the option achieving a greater energy saving in current and future scenarios, and the use of energy was greatly reduced in those zones characterized by having a greater cooling energy consumption. Moreover, the differences of energy consumption between the adaptive models in the cities and years generated that the clusters presented differences among all cities, so such scenarios are required to be considered for future interventions. This research is the transition towards the goals proposed by the European Union for 2050.