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Thermal Energy Management in Buildings

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "J: Thermal Management".

Deadline for manuscript submissions: closed (25 June 2021) | Viewed by 32853
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Guest Editor
Faculty of Engineering, University of Porto, 4099-002 Porto, Portugal
Interests: energy; efficient buildings; sustainability; porous media; heat transfer; mass transfer; fluid flow; drying and wetting; moisture transport; numerical simulation
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Guest Editor
Faculty of Engineer, University of Porto, 4099-002 Porto, Portugal
Interests: 3D printing for construction; building pathology and rehabilitation; energy and hygrothermal behaviour
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Guest Editor
LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portuga
Interests: solar redox flow cells; photoelectrochemical water splitting; perovskite solar cells (PSC); dye-sensitized solar cells (DSSC); photoelectrochemical devices; electrochemical devices; fuels
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Special Issue Information

Dear Colleagues,

Since 50 years ago, the energy demand from buildings (residential and commercial) has grown by 1.8% per year, and it is predicted to grow from 2790 Mtoe (i.e., 116.8 EJ) in 2010, to over 4400 Mtoe by 2050, with most of this increase being from developing countries. Three-quarters of the total energy consumption in the buildings sector is residential, where there is great potential to improve energy efficiency. There is a presumption and need for these requirements to be applied, not only to new buildings, but also to the existing ones.

In the early of 2010’s, this objective was viewed as unrealistic. Now, with emerging materials for thermal energy management, the PV panels’ reduction of costs, and with the development electrochemical storage energy (batteries) and simulation technologies, suddenly, researchers and investors, and consequently, politicians, began to see this directive as possible, necessary, and potentially interesting to invest in.

The purpose of this Energies Special Issue on “Thermal Energy Management in Buildings” is to publish a set of research articles that demonstrate the effectiveness of innovative concepts, solutions, and materials, to fulfil the maximum building energy demands, meeting the long-term and changing needs and requirements of building users.

We invite researchers to contribute original research articles, as well as review articles that will stimulate the continuing efforts to understand the recent advances and innovation in these research fields. We are particularly interested in articles describing the recent trends, developments, and applications of new thermal energy management solutions capable of fulfilling the electrical, thermal, and cooling demands of low-energy consumption buildings. Manuscripts combining experimental implementation with theoretical calculations and techno-economic assessment are welcome.

Potential topics include, but are not limited to, the following:

  • Emerging materials for thermal energy management
  • Energy storage systems, including phase change materials and batteries
  • Advanced insulation materials, components, and systems
  • Modelling of advanced materials and technologies in buildings
  • Energy consumption in buildings
  • Near-zero energy buildings (nZEB’s) and zero energy buildings (ZEB’s)
  • Optimized solar-oriented envelope designs
  • Strong integration of renewable technologies
  • Improved air-tightness and highly efficient air conditioning systems
  • Economic/functional merit factor
  • Life-cycle assessment (LCA)
  • Energy policy

Dr. João M.P.Q. Delgado
Prof. Ana Sofia Guimarães
Prof. Adélio Mendes
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • emerging materials
  • energy management
  • energy consumption
  • renewable technologies
  • energy policy

Published Papers (11 papers)

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Research

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30 pages, 7249 KiB  
Article
Evaluation of Indoor Thermal Environmental Conditions of Residential Buildings in Saudi Arabia
by Mosaab Alaboud and Mohamed Gadi
Energies 2022, 15(5), 1603; https://doi.org/10.3390/en15051603 - 22 Feb 2022
Cited by 1 | Viewed by 2741
Abstract
The Saudi Arabian climate, generally speaking, is known to be hot and arid. Even with its extensive energy resources, Saudi Arabia is not immune to the demands of climate change. Over 50% of the country’s electricity is consumed by residential buildings. For economic, [...] Read more.
The Saudi Arabian climate, generally speaking, is known to be hot and arid. Even with its extensive energy resources, Saudi Arabia is not immune to the demands of climate change. Over 50% of the country’s electricity is consumed by residential buildings. For economic, fiscal, and environmental reasons, government policy is to stem the profligate use of finite energy resources. It is incumbent on the Saudi building industry to adapt to changing conditions by re-assessing the choice of materials and the design and lay-out of new buildings to help quell demands for air-conditioning during the hotter parts of the year. Throughout the country, electricity consumption doubles in the summer months. Given this situation, this study explores the indoor thermal environment typical of residential buildings. The study selected one house located in a hot dry climatic region as a case study. The features of the house were assessed to determine the permeable features that require improvement. Two main methods used to evaluate indoor thermal conditions are physical measurements and computer modelling. Instruments were used to monitor the house during both summer and winter months. Thermal analysis software was used to model the thermal properties of the house for two purposes, first, to assess the thermal performance of the case-study building, and second, to identify areas in which improvements could be made using proposed alternative materials. Different parts of the building were simulated using different material combinations to achieve the optimal cooling reduction. The findings suggest that the cooling load can be reduced of up to 56.4%. Consequently, the intensity of the proposed annual cooling for the chosen house was predicted to be 79.7 kWh/m2/y. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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13 pages, 3434 KiB  
Article
Design and Parametric Investigation of an Efficient Heating System, an Effort to Obtain a Higher Seasonal Performance Factor
by Trond Thorgeir Harsem, Behrouz Nourozi, Amirmohammad Behzadi and Sasan Sadrizadeh
Energies 2021, 14(24), 8475; https://doi.org/10.3390/en14248475 - 15 Dec 2021
Cited by 8 | Viewed by 2447
Abstract
The present work introduces an innovative yet feasible heating system consisting of a ground source heat pump, borehole thermal energy storage, an auxiliary heater, radiators, and ventilation coils. The concept is developed by designing a new piping configuration monitored by a smart control [...] Read more.
The present work introduces an innovative yet feasible heating system consisting of a ground source heat pump, borehole thermal energy storage, an auxiliary heater, radiators, and ventilation coils. The concept is developed by designing a new piping configuration monitored by a smart control system to reduce the return flow temperature and increase the temperature differential between the supply and return flows. The radiators and ventilation heating circuits are connected in series to provide the heat loads with the same demand. The investigation of the proposed model is performed through developed Python code considering a case study hospital located in Norway. The article presents, after validation of the primary heating system installed in the hospital, a parametric investigation to evaluate the effect of main operational parameters on the performance metrics of both the heat pump and the total system. According to the results, the evaporator temperature is a significant parameter that considerably impacts the system performance. The parametric study findings show that the heat pumps with a thermal capacity of 400 kW and 600 kW lead to the highest heat pump and total seasonal performance factors, respectively. It is also observed that increasing the heat pump capacity does not affect the performance indicators when the condensation temperature is 40 °C and the heat recovery is 50%. Moreover, choosing a heat pump with a smaller capacity at the heat recovery of 75% (or higher) would be an appropriate option because the seasonal performance values are not varied by changing the heat pump capacity. The results reveal that reducing return temperature under a proper parameters selection results in substantially higher seasonal performance factors of the heat pump and total system. These outcomes are in-line with the United Nations sustainable development goals including Sustainable Cities and Communities. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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14 pages, 282 KiB  
Article
Advanced Manufacturing in Civil Engineering
by Ana S. Guimarães, João M. P. Q. Delgado and Sandra S. Lucas
Energies 2021, 14(15), 4474; https://doi.org/10.3390/en14154474 - 24 Jul 2021
Cited by 8 | Viewed by 3065
Abstract
The main goal of this work is the analysis of potential energy and green benefits of 3D printing on building construction. Current literature reports a considerable number of benefits for 3D printing, namely, reduction of material use, lower operational costs and time-saving. The [...] Read more.
The main goal of this work is the analysis of potential energy and green benefits of 3D printing on building construction. Current literature reports a considerable number of benefits for 3D printing, namely, reduction of material use, lower operational costs and time-saving. The authors also mention design freedom, higher efficiency, productivity and quality. This work presents the latest developments in 3D printing in civil engineering, namely, a review of the last 3D printing projects and the limitations of construction 3D printing with a focus on large-scale applications, technology costs, mix development and optimisation and thermal behaviour. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
26 pages, 2459 KiB  
Article
Unsteady Coupled Moisture and Heat Energy Transport through an Exterior Wall Covered with Vegetation
by Leopold Škerget, António Tadeu and João Almeida
Energies 2021, 14(15), 4422; https://doi.org/10.3390/en14154422 - 22 Jul 2021
Cited by 4 | Viewed by 2011
Abstract
A mathematical model that governs unsteady coupled moisture and heat energy transport through an exterior wall covered with vegetation is described. The unknown temperature and moisture content of the plants and canopy air are represented by a system of nonlinear ordinary differential equations [...] Read more.
A mathematical model that governs unsteady coupled moisture and heat energy transport through an exterior wall covered with vegetation is described. The unknown temperature and moisture content of the plants and canopy air are represented by a system of nonlinear ordinary differential equations (ODEs). The transport of moisture and heat through the support structure, which includes insulation and soil layers, is defined in a series of nonlinear partial differential equations (PDEs). After setting out the model, this article presents and discusses a set of numerical applications. First, a simplified system consisting of a brick wall covered with climbing vegetation is used to study the role of individual variables (e.g., wind speed, minimum stomatal internal leaf resistance, leaf area index, and short-wave extinction coefficient) on the hygrothermal behaviour of the green wall. Thereafter, more complex green wall systems comprising a bare concrete wall, mortar, cork-based insulation (ICB), soil and vegetation are used to evaluate the influence of the thermal insulation and substrate layers on the heat flux distribution over time at the interior surface of the wall, and on the evolution of the relative humidity, water content, and temperature throughout the cross section of the green wall. The numerical experiments proved that vegetation can effectively reduce exterior facade surface temperatures, heat flux through the building envelope and daily temperature fluctuations. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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27 pages, 7977 KiB  
Article
Modelling of Solar Irradiance Incident on Building Envelopes in Polish Climatic Conditions: The Impact on Energy Performance Indicators of Residential Buildings
by Piotr Michalak
Energies 2021, 14(14), 4371; https://doi.org/10.3390/en14144371 - 20 Jul 2021
Cited by 10 | Viewed by 2995
Abstract
In this study, we use the data of Polish typical meteorological years and 15 transposition models to obtain global solar irradiance on sloped surfaces to calculate solar irradiance on external building partitions, solar gains, heating demands, and primary nonrenewable energy for heating and [...] Read more.
In this study, we use the data of Polish typical meteorological years and 15 transposition models to obtain global solar irradiance on sloped surfaces to calculate solar irradiance on external building partitions, solar gains, heating demands, and primary nonrenewable energy for heating and domestic hot water (EPH+W) of two typical Polish residential buildings, each for two variants in five locations. In relation to TMYs, annual solar gains were lower by −31% and −36% on average in a single and multifamily building, respectively, and the annual heating demands increased by 9% and 16%, respectively. Consequently, averaged EPH+W in relation to TMYs rose by 1.4 kWh/m2 and 4.5 kWh/m2, respectively. The mean differences between TMYs and the new method from the recently published EN-ISO 52010 standard for test Building 1 were 1.6 and 1.2 kWh/m2, for Variants 1 and 2, respectively. Similarly, for test Building 2, the mean differences were 5.1 kWh/m2 and 3.9 kWh/m2, respectively. This means that the simulation model that is chosen has a visible impact on a building’s energy performance indicators and its rating without any changes in the physical structure and use of the building. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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25 pages, 5368 KiB  
Article
Using PCM in Two Proposed Residential Buildings in Christchurch, New Zealand
by Erik Schmerse, Charles A. Ikutegbe, Amar Auckaili and Mohammed M. Farid
Energies 2020, 13(22), 6025; https://doi.org/10.3390/en13226025 - 18 Nov 2020
Cited by 12 | Viewed by 2689
Abstract
A characteristic feature of lightweight constructions is their low thermal mass which causes high internal temperature fluctuations that require high heating and cooling demand throughout the year. Phase change materials (PCMs) are effective in providing thermal inertia to low-thermal-mass buildings. This paper aims [...] Read more.
A characteristic feature of lightweight constructions is their low thermal mass which causes high internal temperature fluctuations that require high heating and cooling demand throughout the year. Phase change materials (PCMs) are effective in providing thermal inertia to low-thermal-mass buildings. This paper aims to analyse the thermal behaviour of two proposed lightweight buildings designed for homeless people and to investigate the potential benefit achievable through the use of different types of PCM in the temperate climatic conditions of Christchurch, New Zealand. For this purpose, over 300 numerical simulations were conducted using DesignBuilder® simulation software. The bulk of the simulations were carried out under the assumption that the whole opaque building envelope is equipped with PCM. The results showed significant energy saving and comfort enhancement through the application of PCMs. The integration of PCM in single-structure components led to substantial energy savings between 19% and 27% annually. However, occupant behaviour in terms of ventilation habits, occupancy of zones, etc. remains one of the biggest challenges in any simulation work due to insufficient data. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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23 pages, 8976 KiB  
Article
Assessing the Magnitude and Likely Causes of Summertime Overheating in Modern Flats in UK
by Rajat Gupta and Matt Gregg
Energies 2020, 13(19), 5202; https://doi.org/10.3390/en13195202 - 6 Oct 2020
Cited by 11 | Viewed by 2325
Abstract
There has been increasing recognition that climate change may lead to risk of summertime overheating in UK dwellings with potentially adverse consequences for human comfort and health. This paper investigates the magnitude of summertime overheating over one month in 2017, in four new [...] Read more.
There has been increasing recognition that climate change may lead to risk of summertime overheating in UK dwellings with potentially adverse consequences for human comfort and health. This paper investigates the magnitude of summertime overheating over one month in 2017, in four new flats built to identical thermal standards, with similar occupancy patterns and located in the same block in a development in Southeast England. Both static and adaptive methods were used to assess the overheating risk, while the variation in indoor temperatures across the flats was examined through key building characteristics including floor level, glazing orientation, exposed surface area to floor area ratio (SA/FA), glazing area to floor area ratio, and ventilation. Data collection included continuous monitoring of indoor and outdoor temperature, relative humidity, CO2 levels and opening/closing of windows. Summertime overheating was found to be prevalent in all four flats but was most pronounced in two top floor flats with high SA/FA ratio and east/west facing glazing. Due to limited window opening and locational limitations of one flat, some conclusions were derived from three flats. Though the study sample is small, it is clear that overheating in new housing is a current issue and designing for avoidance of summertime overheating should become mainstream. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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32 pages, 18257 KiB  
Article
Phase Change Material Melting Process in a Thermal Energy Storage System for Applications in Buildings
by Túlio Nascimento Porto, João M. P. Q. Delgado, Ana Sofia Guimarães, Hortência Luma Fernandes Magalhães, Gicelia Moreira, Balbina Brito Correia, Tony Freire de Andrade and Antonio Gilson Barbosa de Lima
Energies 2020, 13(12), 3254; https://doi.org/10.3390/en13123254 - 23 Jun 2020
Cited by 12 | Viewed by 3715
Abstract
The development of thermal energy storage systems is a possible solution in the search for reductions in the difference between the global energy supply and demand. In this context, the ability of some materials, the so-called phase change materials (PCMs), to absorb and [...] Read more.
The development of thermal energy storage systems is a possible solution in the search for reductions in the difference between the global energy supply and demand. In this context, the ability of some materials, the so-called phase change materials (PCMs), to absorb and release large amounts of energy under specific periods and operating conditions has been verified. The applications of these materials are limited due to their low thermal conductivity, and thus, it is necessary to associate them with high-conductivity materials, such as metals, to make the control of energy absorption and release times possible. Bearing this in mind, this paper presents a numerical analysis of the melting process of a PCM into a triplex tube heat exchanger (TTHX) with finned copper tubes, which allowed for the heat transfer between a heating fluid (water) and the phase change material to power a liquid-desiccant air conditioning system. Through the analysis of the temperature fields, liquid fractions, and velocities, as well as the phase transition, it was possible to describe the material charging process; then, the results were compared with experimental data, which are available in the specialized literature, and presented mean errors of less than 10%. The total required time to completely melt the PCM was about 105.5 min with the water being injected into the TTHX at a flow rate of 8.3 L/min and a temperature of 90 °C. It was observed that the latent energy that accumulated during the melting process was 1330 kJ, while the accumulated sensitive energy was 835 kJ. The average heat flux at the internal surface of the inner tube was about 3 times higher than the average heat flux at the outer surface of the TTHX intermediate tube due to the velocity gradients that developed in the internal part of the heat exchanger, and was about 10 times more intense than those observed in the external region of the equipment. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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22 pages, 5697 KiB  
Article
Industrial Ceramic Blocks for Buildings: Clay Characterization and Drying Experimental Study
by A.M. Vasconcelos da Silva, J.M.P.Q. Delgado, A.S. Guimarães, W.M.P. Barbosa de Lima, R. Soares Gomez, R. Pereira de Farias, E. Santana de Lima and A.G. Barbosa de Lima
Energies 2020, 13(11), 2834; https://doi.org/10.3390/en13112834 - 2 Jun 2020
Cited by 7 | Viewed by 2389
Abstract
The conformation of a ceramic piece follows the steps of preparing the raw material, molding, lamination, drying, and firing. Drying is a thermodynamic process of heat and mass transfer, with dimensional variations of the product that requires a large amount of energy. Ceramic [...] Read more.
The conformation of a ceramic piece follows the steps of preparing the raw material, molding, lamination, drying, and firing. Drying is a thermodynamic process of heat and mass transfer, with dimensional variations of the product that requires a large amount of energy. Ceramic materials when exposed to non-uniform drying may suffer cracks and deformations, reducing their post-drying quality. Thus, this work aimed to study the drying of industrial ceramic blocks in an oven with forced air circulation. Experiments were carried out to characterize the clay and drying of the ceramic block at temperatures ranging from 50 °C to 100 °C. Results of the chemical, mineralogical, granulometric, differential thermal, and thermogravimetric analysis of the clay, and heating kinetics, mass loss, and dimensional variation of the industrial ceramic block are presented and analyzed in detail. It was found that the clay is basically composed of silica and alumina (≈ 80.96%), with an average particle diameter of 13.36 μm. The study proved that drying at high temperature and low relative humidity of the air generates high rates of mass loss, heating, and volumetric shrinkage in the ceramic product, and high thermo-hydraulic stresses, which cause the appearance and propagation of cracks, gaps, and cleavages, compromising the final quality of the product. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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19 pages, 10615 KiB  
Article
FEM Applied to Building Physics: Modeling Solar Radiation and Heat Transfer of PCM Enhanced Test Cells
by Ana Vaz Sá, Miguel Azenha, A.S. Guimarães and J.M.P.Q. Delgado
Energies 2020, 13(9), 2200; https://doi.org/10.3390/en13092200 - 2 May 2020
Cited by 4 | Viewed by 2699
Abstract
In passive solar buildings, energy can be stored using either sensible heat materials or latent heat materials. Phase change materials (PCM) can contribute to temperature control in passive solar buildings when melting occurs near to comfort temperature required for building’s interior spaces. The [...] Read more.
In passive solar buildings, energy can be stored using either sensible heat materials or latent heat materials. Phase change materials (PCM) can contribute to temperature control in passive solar buildings when melting occurs near to comfort temperature required for building’s interior spaces. The use of finite element method (FEM) as a numerical methodology for solving the thermal problem associated with heat transfer in current building materials and PCMs make sense, as it is a well-known technique, generalized and dominated, however, still little applied to the domain of building physics. In this work, a solar model was developed and applied in order to simulate numerically the effect of solar radiation incidence on each face of the test cells (with different solar exposures) without neglecting the main objective of the recommended numerical simulation: the study of the action of PCM. During the experimental campaign, two test cells with distinct inner layers were used to evaluate the effect of solar radiation: (i) REFM test cell (without PCM) with a reference mortar; (ii) PCMM test cell (with PCM) with a PCM mortar. The temperatures monitored inside the REFM and PCMM test cells were compared with the values resulting from the numerical simulation, using FEM with 3D discretization and the explicit modeling of the solar radiation, and the obtained results revealed a significant coherence of values. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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Review

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31 pages, 6599 KiB  
Review
Linking Energy Poverty with Thermal Building Regulations and Energy Efficiency Policies in Portugal
by Ana Mafalda Matos, João M. P. Q. Delgado and Ana Sofia Guimarães
Energies 2022, 15(1), 329; https://doi.org/10.3390/en15010329 - 4 Jan 2022
Cited by 15 | Viewed by 3539
Abstract
Energy-poverty (EP) must be considered an energy-related issue since buildings are a central part of people’s daily lives. Thus, it has an important role in energy-related policy implementation. Even though the European Union (EU) has endorsed general energy efficiency through the Energy Efficiency [...] Read more.
Energy-poverty (EP) must be considered an energy-related issue since buildings are a central part of people’s daily lives. Thus, it has an important role in energy-related policy implementation. Even though the European Union (EU) has endorsed general energy efficiency through the Energy Efficiency Directive and Energy Performance of Buildings Directive recast, it was the Clean Energy Package for all Europeans that clearly highlighted EP. The growing concerns with EP have also been emphasised in subsequent directives and initiatives. Despite some regulatory framework and the milder climate situation, the proportion of the population experiencing thermal discomfort in southern and eastern European countries, namely in the winter season, is relatively high, reflecting the poor thermal performance of building stock, low family incomes and high energy prices, among others. The current work analysed the EP evolution in Portugal in the EU context, and the Thermal Building Regulations and Energy Efficiency Policies developed, aiming to add insight into the effectiveness of those policies concerning EP mitigation in Portugal as an EU Member state. Moreover, a critical debate on the potential to lower the EP Portuguese situation was also an objective to pursue. It is plausible to admit that reducing EP by acting on residential building stock, namely through the increase of energy efficiency and comfort, plays a key role in improving the living conditions, namely of vulnerable households and deprived areas. This will also decrease energy consumption and dependence while further promoting a smarter, sustainable and inclusive society, contributing to economic growth. Full article
(This article belongs to the Special Issue Thermal Energy Management in Buildings)
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