Passive House Optimization for Portugal: Overheating Evaluation and Energy Performance

Antonio Figueiredo, Jérôme Henri Kämpf
Elsevier, 2016
Article

Résumé

Improving common constructive solutions and substituting HVAC systems for more efficient ventilation systems leads to significant opportunities to decrease energy demand for heating and cooling and for improving occupant’s comfort. Passive House (PH) concept adapted to Mediterranean countries is regarded as a necessary strategy for reducing global energy consumption and greenhouse gas emissions at the building level. The present research, undertakes the Passive House concept optimization for the Portuguese climate, using a real building case, built according the national thermal code and classified as a plus building. The goal consists in complying with PH requirements through the definition of the external envelope solutions as well as the heating and cooling systems to be applied to new or refurbished buildings. The research starts for the Aveiro region climate (site built) and a broader analysis for different regions of Portugal mainland were performed. The building simulated is a detached house of contemporary architecture with the numerical model developed based on the original patented design solution and dynamic simulation realized with EnergyPlus® software. In a first approach and from the original model, sensitivity analysis and multi-objective optimization with an evolutionary algorithm were carried out in order to assess the reduction potential of the annual energy consumption. From the results long periods of thermal discomfort for the heating season (from 60 to 92%) were observed, as well as long periods of overheating during the summer (from 13 to 43%). Comparing one of the best solutions attained with the original case study, a reduction of 42% of the heating energy demand and the reduction of 64% of the cooling demand was achieved. Then, in a second approach the evolutionary algorithm was used to meet the compliant parameters defined by PH standards for different regions in Portugal mainland. The multi-objective optimization was developed to study the interaction between annual heating demand and summer thermal overheating rate objectives and assess their trade-offs. It was concluded that the Passive House concept is viable for the Portuguese climate; however it is essential to adapt and detail the technical and constructive solutions for different regions.

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https://infoscience.epfl.ch/record/219183?ln=fr

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Antonio Figueiredo, Jérôme Henri Kämpf
Elsevier, 2016
Article

Résumé

Official source

https://infoscience.epfl.ch/record/219183?ln=fr

À propos de ce résultat

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Concepts associés

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Publications associées (13)

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Novel models towards predictive control of advanced building systems and occupant comfort in buildings

Nikolaos Zarkadis

People in developed countries spend today most of their time inside buildings as part of the modern way of life. As a result, the building sector accounts for almost 40% of the total energy consumption and a big part of the energy bill goes to maintain the visual and thermal comfort of their occupants. At the same time, awareness is being raised during the last decades about the greenhouse gas emissions and the possibly irreversible effects of global warming; both linked to excessive use of non-renewable primary energy sources which still power most of the world, including our buildings. Thus, moderating the energy consumed in them is a top priority. However, this does not imply a horizontal cut in energy consumption that would result in a drop of user comfort. Instead, we suggest that improving energy efficiency in buildings while maintaining or even improving the user comfort is the optimal solution. It is indeed the core of this thesis that there is a great energy saving potential in refining the control of building systems such as electric lighting, heating, cooling and ventilation, which more than often consume a lot of energy without delivering the analogous amount of visual and thermal comfort. In this direction, this thesis proposes the development of a novel predictive control algorithm for the control of electrochromic glazing using a low cost sky scanner using a simple web camera. The developed algorithm demonstrated an average prediction accuracy of 92% and integrates and controls the blinds and electric lighting to maximise visual comfort taking into account outdoor and indoor conditions, presence and user actions. Measurements and extensive simulations showed that the elaborated algorithm improves thermal and visual comfort when compared to standard glazing coupled with blinds and exhibits acceptable levels of energy consumption for space heating and electric lighting. In the same subject of improving building control, a novel approach for controlling building systems by using state-based stochastic data-driven models to identify "season" is defined and developed. We reason that the season variable is unique to every building and it depends on weather conditions, user behaviour and building construction. The developed models identified "season" with an accuracy that ranged from 69 to 91% and it was shown through simulations that a controller based on Hidden Markov Models can reduce energy demand for heating and improve the thermal comfort of occupants in different building construction types. Finally, the use of Hidden Markov Models was further explored in this thesis by suggesting a novel model for the estimation of occupants' visual comfort in buildings. The proposed model is based on horizontal workplane illuminance measurements using ceiling-mounted sensors as well on vertical illuminance monitoring at the observer's eyes plane (pupillary illuminance) by means of wearable portable sensors. We argue that the proposed model improves greatly over the various existing discomfort glare indices and metrics and it is also convincingly demonstrated that it can be seamlessly integrated and used in building automation systems based on fuzzy logic.

EPFL2015

Chargement

The sun is the biggest known source of energy in our solar system. We feel its strength when it gets hot during the the day and we notice its absence during the night when we feel cold. So as to be less dependent on the sun as an energy source, we implemented additional heating and cooling sources to maintain the temperature within a comfortable range. The downside to this is that the majority of energy consumed within the housing sector is used up on the heating and cooling alone. To profit from the vast energy source of the sun we propose a user-adaptive and building-adaptive blind control for residential buildings, that is implemented in prefabricated modules for facade renovation. User-adaptive means that it is the occupant who is responsible for the temperature control within the home. Building-adaptive, in this context, means that the temperature control is established automatically without any user input. Through the evaluation of occupant queries we have shown that a general measure for thermal comfort is not possible for all occupants. Consequently, there is a need for a personalized measure of thermal comfort. In order to create this the occupant enters votes via the interface; from this we deduced statistically the probability of comfort relative to the indoor temperature. According to the profile the control sets its target temperature. The profile steadily adapts the user's preferences and through this we can also capture seasonal changes in comfort temperature. This guarantees that at each point in time the control system knows the desired temperature and is taking action to achieve it. The adaption to the building is achieved with the fitting of a simple thermal building model with data collected by the sensors of the control system. We showed that the monitored data sufficiently fits the model. With the help of the simple model we evaluated different control strategies and optimized them according to the thermal profile. For our performance tests we conducted computer simulations as well as a 6-month field study. For the simulations, a specific test bed was suggested that would assess the saving potential, which can then be compared to the performance of the tested control. Results showed that the suggested control system is capitalizing on most of the achievable energy savings and thermal comfort. A 6-month field study in the LESO-PB building was carried out to test the impact on energy demand as well as comfort under real conditions. It appeared that the automatically controlled office needed only approximately 50% of the average heating energy that was used in the manually controlled offices. Furthermore, the probability of thermal comfort was, on average, 10% higher in the automatically controlled offices when compared to those that were controlled manually.

EPFL2011

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Energy Demand Analysis for Building Envelope Optimization for Hot Climate: A Case Study at AN Najah National University

Silvia Coccolo, Jérôme Henri Kämpf, Dasaraden Mauree, Sameh Monna, Jean-Louis Scartezzini

The study aims to analyse the heating and cooling demand of the An Najah university campus, and to optimize the building envelope for selected buildings, in order to achieve energy efficiency, and make use of renewable solar energy. Building and urban simulation programs are used to evaluate the effects of applying different technologies and design strategies on the energy consumption. The university campus hosts 11 university buildings. The proposed methodology makes use of an urban energy modelling tool, called CitySim and Design Builder based on EnergyPlus model to analyse the heating and cooling demand of the university campus and assess the solar potential of the site. The energy calculation considers the hourly heating and cooling demand per building, and for the whole campus. The solar irradiation received by the buildings envelope (walls and roofs) consider the impact of the urban environment, including the inter-reflections between buildings and albedo of the outdoor surfaces. The climatic data provided by Meteonorm. The geometrical information of the campus and selected buildings retrieved by GIS while the physical characteristics of buildings are based on on-site previous studies. The results point to the potential for a significant decrease in energy consumption for cooling and heating.

2016

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Novel models towards predictive control of advanced building systems and occupant comfort in buildings

Nikolaos Zarkadis

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EPFL2011