Unsteady simulation of energy performance and thermal comfort in non-residential buildings

Improving the energy efficiency of existing buildings by implementing building automation control strategies (BACS) besides building envelope and energy system retrofitting has been recommended by the Energy Performance of Buildings Directive (EPBD) 2018. This paper investigated this recommendation by conducting a simulation-based optimization to explore cost-effective retrofitting combinations of building envelope, energy systems and BACS measures in-line with automation standard EN 15232. Two cases (i.e., a typical single-family house and apartment block) were modeled and simulated using IDA Indoor Climate and Energy (IDA-ICE). The built-in optimization tool, GenOpt, was used to minimize energy consumption as the single objective function. The associated difference in life cycle cost, compared to the reference design, was calculated for each optimization iteration. Thermal comfort of the optimized solutions was assessed to verify the thermal comfort acceptability. Installing an air source heat pump had a greater energy-saving potential than reducing heat losses through the building envelope. Implementing BACS achieved cost-effective energy savings up to 24%. Energy savings up to 57% were estimated when BACS was combined with the other retrofitting measures. Particularly for compact buildings, where the potential of reducing heat losses through the envelope is limited, the impact of BACS increased. BACS also improved the thermal comfort.

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Impact of urban temperatures on energy performance and thermal comfort in residential buildings. The case of Rome, Italy

Energy and Buildings ◽

10.1016/j.enbuild.2017.05.021 ◽

2017 ◽

Vol 157 ◽

pp. 20-29 ◽

Cited By ~ 21

Author(s):

M. Zinzi ◽

E. Carnielo

Keyword(s):

Thermal Comfort ◽

Residential Buildings ◽

Energy Performance

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Building-Information-Modelling-Based Thermal-Energy Performance Evaluation of Silica-Aerogel-Incorporated Rigid Board Roof Insulation Material for Residential Buildings in the Tropical Climate of Malaysia

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/945/1/012066 ◽

2021 ◽

Vol 945 (1) ◽

pp. 012066

Author(s):

Nadzhratul Husna ◽

Syed Ahmad Farhan ◽

Mohamed Mubarak Abdul Wahab ◽

Nasir Shafiq ◽

Muhammad Taufiq Sharif ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Comfort ◽

Thermal Energy ◽

Silica Aerogel ◽

Residential Buildings ◽

Energy Performance ◽

Insulation Material ◽

Building Information Modelling ◽

Indoor Thermal Comfort ◽

Building Information

Abstract Malaysia is located in the equator, with a hot and humid climate. The highest temperature recorded during the day was 39 °C, which leads to discomfort among building occupants, in particular, residential buildings, where indoor thermal comfort is of a higher priority compared to other types of buildings. Hence, the thermal performance of the residential roof assembly needs to be improved to lower the indoor temperature and, accordingly, maintain the level of indoor thermal comfort. In view of the need to improve the thermal performance, a silica-aerogel-incorporated rigid board roof insulation material for residential buildings was developed using kapok fibre, high density polyethylene (HDPE) and silica aerogel. The thermal conductivity of the material was measured. The sample with 4 wt. % and 5 wt. % of silica aerogel content obtained the lowest thermal conductivity of 0.04 W/mK. Silica aerogel content of above 4 wt. % did not result in further reduction of the thermal conductivity. Therefore, it can be concluded that the optimum silica aerogel content for the sample was 4 wt. %. Building-Information-Modelling (BIM)based thermal-energy performance evaluation of the material was performed by generating temperature and cooling load data using Integrated Environmental Solution-Virtual Environment to validate the thermal-energy performance of the material, by installing the material within the roof assembly of a residential BIM. Findings indicate that the material can potentially be employed in the future as a roof insulation material to maintain the level of indoor thermal comfort among residential building occupants.

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Modeling the Evolution of Construction Solutions in Residential Buildings’ Thermal Comfort

Applied Sciences ◽

10.3390/app11052427 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2427

Author(s):

Inês F. G. Reis ◽

António Figueiredo ◽

António Samagaio

Keyword(s):

Thermal Comfort ◽

Phase Change Materials ◽

Residential Buildings ◽

Thermal Inertia ◽

Thermal Fluctuations ◽

Energy Performance ◽

Regulatory Requirements ◽

Thermal Discomfort ◽

High Thermal Inertia ◽

Global Energy Consumption

The evolution of the construction sector over the years has been marked by the replacement of high thermal inertia mass constructions by increasingly lighter solutions that are subject to greater thermal fluctuations and, consequently, thermal discomfort. To minimize these effects, energy demanding space conditioning technologies are implemented, contributing significantly to the sector’s share of global energy consumption. Enhanced constructive solutions involving phase-change materials have been developed to respond to the constructive thermal inertia loss, influencing buildings’ thermal and energy performance. This work aims to model the evolution of the construction over the last decades to understand to what extent constructive characteristics influence the occupants’ thermal comfort. For this purpose, typical and enhanced solutions representing distinct constructive periods were simulated using the EnergyPlus® software through its graphical interface DesignBuilder® and the thermal comfort of the different solutions was evaluated using the adaptive model for thermal comfort EN16798-1. The main results reveal that more restraining regulatory requirements are indeed mitigating thermal discomfort situations. However, overheating phenomena can rise, creating worrying consequences in the short-medium term. Thus, countries with mild climates such as Portugal, must pay special attention to these effects, which may be aggravated by climate change.

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Variables of influence on thermal performance of buildings under transient conditions

PARC Pesquisa em Arquitetura e Construção ◽

10.20396/parc.v12i00.8661655 ◽

2021 ◽

Vol 12 ◽

pp. e021023

Author(s):

Camila Carvalho Ferreira ◽

Henor Artur de Souza ◽

Joyce Correna Carlo

Keyword(s):

Thermal Comfort ◽

Thermal Performance ◽

Natural Ventilation ◽

Residential Buildings ◽

Performance Standards ◽

Gain Coefficient ◽

Energy Performance ◽

Single Family ◽

Hot Climate ◽

Climate Analysis

Residential buildings significantly increase electricity demand, especially in developing countries. In this case, the requirements addressed by the standards can ensure the climatic adequacy of the envelope, enhance thermal performance, and promote thermal comfort conditions while reducing energy consumption. However, the criteria for evaluating the thermal performance of a building’s envelope that is commonly adopted in energy performance standards and codes have proved to be inefficient in hot climates. The heat exchanges within buildings are dependent on solar radiation and ventilation. The purpose of this article is to establish the variables with the greatest influence on the thermal performance of naturally ventilated dwellings in hot climates (equatorial, tropical and subtropical). For this investigation, a factorial design was adopted for sensitivity analysis. The structure of the factorial experiment defined the simulations of four patterns of single-family and multifamily residential buildings. We varied the thermophysical properties of the external walls and roofs, the heat gain coefficient of the openings, and natural ventilation. Brazil was adopted as a basis for climate analysis, including equatorial, tropical and subtropical climates. The analyses were based on comfort hours in an adaptive model and statistically evaluated using Analysis of Variance (ANOVA) tests. In general, the absorption of the walls and cover, the thermal transmittance of the cover and the natural ventilation were the variables of greatest influence on thermal comfort in a hot climate.

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Effects of Climate Change for Thermal Comfort and Energy Performance of Residential Buildings in a Sub-Saharan African Climate

Buildings ◽

10.3390/buildings9100215 ◽

2019 ◽

Vol 9 (10) ◽

pp. 215 ◽

Cited By ~ 6

Author(s):

Dodoo ◽

Ayarkwa

Keyword(s):

Climate Change ◽

Thermal Comfort ◽

Energy Demand ◽

Residential Buildings ◽

Energy Performance ◽

Simulation Software ◽

Indoor Climate ◽

Recent Climate ◽

Sub Saharan ◽

Cooling Energy Demand

This study presents an analysis of the impacts of climate change on thermal comfort and energy performance of residential buildings in Ghana, in sub-Saharan Africa, and explores mitigation as well as adaptation strategies to improve buildings’ performance under climate change conditions. The performances of the buildings are analyzed for both recent and projected future climates for the Greater Accra and Ashanti regions of Ghana, using the IDA-ICE dynamic simulation software, with climate data from the Meteonorm global climate database. The results suggest that climate change will significantly influence energy performance and indoor comfort conditions of buildings in Ghana. However, effective building design strategies could significantly improve buildings’ energy and indoor climate performances under both current and future climate conditions. The simulations show that the cooling energy demand of the analyzed building in the Greater Accra region is 113.9 kWh/m2 for the recent climate, and this increases by 31% and 50% for the projected climates for 2030 and 2050, respectively. For the analyzed building in the Ashanti region, the cooling energy demand is 104.4 kWh/m2 for the recent climate, and this increases by 6% and 15% for the 2030 and 2050 climates, respectively. Furthermore, indoor climate and comfort deteriorate under the climate change conditions, in contrast to the recent conditions.

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Effect of climate change on the energy performance and thermal comfort of high-rise residential buildings in cold climates

MATEC Web of Conferences ◽

10.1051/matecconf/201928202066 ◽

2019 ◽

Vol 282 ◽

pp. 02066

Author(s):

Fuad Mutasim Baba ◽

Hua Ge

Keyword(s):

Climate Change ◽

Energy Consumption ◽

Thermal Comfort ◽

Total Energy ◽

Residential Buildings ◽

Energy Performance ◽

Weather Data ◽

Total Energy Consumption ◽

Climate Zones ◽

High Rise

Buildings now produce more than a third of global greenhouse gases, making them more than any other sector contributing to climate change. This paper investigates the effect of climate change on the energy performance and thermal comfort of a high-rise residential building with different energy characteristic levels, i.e. bylaw to meet current National Energy Code of Canada for Buildings (NECB), and passive house (PH) under two climate zones in British Columbia, Canada. SRES A2, RCP-4.5 and RCP-8.5 emission scenarios are used to generate future horizon weather data for 2020, 2050, and 2080. The simulation results show that for both bylaw and PH cases, the heating energy consumption would be reduced while cooling energy consumption would be increased. As a result, for the bylaw case, the total energy consumption would be decreased for two climate zones, while for PH case, the total energy consumption would be increased for zone 4 and decreased for zone 7. In addition, the number of hours with overheating risks would be increased under future climates, e.g. doubled in 2080, compared to the historical weather data. Therefore, efforts should be made in building design to take into account the impact of climate change to ensure buildings built today would perform as intended under changing climate.

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Testing a Gypsum Composite Based on Raw Gypsum with a Direct Admixture of Paraffin and Polymer to Improve Thermal Properties

Materials ◽

10.3390/ma14123241 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3241

Author(s):

Krzysztof Powała ◽

Andrzej Obraniak ◽

Dariusz Heim

Keyword(s):

Thermal Conductivity ◽

Heat Capacity ◽

Thermal Properties ◽

Phase Change ◽

Large Scale ◽

Building Materials ◽

Residential Buildings ◽

Energy Performance ◽

Polymer Content ◽

Volumetric Heat Capacity

The implemented new legal regulations regarding thermal comfort, the energy performance of residential buildings, and proecological requirements require the design of new building materials, the use of which will improve the thermal efficiency of newly built and renovated buildings. Therefore, many companies producing building materials strive to improve the properties of their products by reducing the weight of the materials, increasing their mechanical properties, and improving their insulating properties. Currently, there are solutions in phase-change materials (PCM) production technology, such as microencapsulation, but its application on a large scale is extremely costly. This paper presents a solution to the abovementioned problem through the creation and testing of a composite, i.e., a new mixture of gypsum, paraffin, and polymer, which can be used in the production of plasterboard. The presented solution uses a material (PCM) which improves the thermal properties of the composite by taking advantage of the phase-change phenomenon. The study analyzes the influence of polymer content in the total mass of a composite in relation to its thermal conductivity, volumetric heat capacity, and diffusivity. Based on the results contained in this article, the best solution appears to be a mixture with 0.1% polymer content. It is definitely visible in the tests which use drying, hardening time, and paraffin absorption. It differs slightly from the best result in the thermal conductivity test, while it is comparable in terms of volumetric heat capacity and differs slightly from the best result in the thermal diffusivity test.

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Experimental Data and Simulations of Performance and Thermal Comfort in a Typical Mediterranean House

Energies ◽

10.3390/en14113311 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3311

Author(s):

Víctor Pérez-Andreu ◽

Carolina Aparicio-Fernández ◽

José-Luis Vivancos ◽

Javier Cárcel-Carrasco

Keyword(s):

Energy Efficiency ◽

Thermal Comfort ◽

Energy Demand ◽

Natural Ventilation ◽

Thermal Characterization ◽

Energy Performance ◽

Building Stock ◽

Energy Demands ◽

Dwelling House ◽

Account Standard

The number of buildings renovated following the introduction of European energy-efficiency policy represents a small number of buildings in Spain. So, the main Spanish building stock needs an urgent energy renovation. Using passive strategies is essential, and thermal characterization and predictive tests of the energy-efficiency improvements achieving acceptable levels of comfort for their users are urgently necessary. This study analyzes the energy performance and thermal comfort of the users in a typical Mediterranean dwelling house. A transient simulation has been used to acquire the scope of Spanish standards for its energy rehabilitation, taking into account standard comfort conditions. The work is based on thermal monitoring of the building and a numerical validated model developed in TRNSYS. Energy demands for different models have been calculated considering different passive constructive measures combined with real wind site conditions and the behavior of users related to natural ventilation. This methodology has given us the necessary information to decide the best solution in relation to energy demand and facility of implementation. The thermal comfort for different models is not directly related to energy demand and has allowed checking when and where the measures need to be done.

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