The Importance of In Situ Characterisation for the Mitigation of Poor Indoor Environmental Conditions in Social Housing

The energy efficiency improvements in existing buildings have become priority concerns of the European Union to encourage energy efficiency amongst residents and buildings as well as facility managers. The characterisation of the building stock plays an important role in the definition of energy renovation strategies. In Portugal, there are over 120,000 social housing flats. This paper focused on the holistic characterisation of a social housing neighbourhood concerning the “in situ” assessment of the indoor environmental conditions and thermal comfort over one year as well as air permeability tests of the flats and evaluation of the energy consumption. The hygrothermal monitoring campaign was carried out using thermo-hygrometer sensors to record the indoor air temperature and relative humidity of a large number of flats over a 12-month period. The airtightness of these flats was determined resourcing fan pressurisation test (blower door test). A relationship between the users’ modifications in the flats and their consequence over the air permeability was pursued and the importance of balconies and exhaust fans for the flats’ air permeability was discussed. The hygrothermal monitoring campaign of the case study was carried out, in order to assess the indoor thermal comfort according the ASHRAE 55 standard. The results show a significant discomfort rate, suggesting that the users are living in unhealthy environmental conditions and the issues that most contribute to the poor indoor environmental conditions that characterise this building stock. In addition, the energy, gas, and water consumption of the flats were collected, and a statistical analysis was performed. Correlations between the variables were observed and two clusters were identified. Cluster 1 includes the lower energy consumption flats, but no real impact on the thermal comfort was found as the entire dataset presented low indoor air temperatures.

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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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Energy models for cost-optimal analysis: Development and calibration of residential reference building models for Northern Cyprus

Indoor and Built Environment ◽

10.1177/1420326x211013076 ◽

2021 ◽

pp. 1420326X2110130

Author(s):

Manta Marcelinus Dakyen ◽

Mustafa Dagbasi ◽

Murat Özdenefe

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

Mean Squared Error ◽

Residential Buildings ◽

Mean Bias Error ◽

Bias Error ◽

Sampled Data ◽

Low Carbon ◽

Building Stock ◽

Northern Cyprus

Ambitious energy efficiency goals constitute an important roadmap towards attaining a low-carbon society. Thus, various building-related stakeholders have introduced regulations targeting the energy efficiency of buildings. However, some countries still lack such policies. This paper is an effort to help bridge this gap for Northern Cyprus, a country devoid of building energy regulations that still experiences electrical energy production and distribution challenges, principally by establishing reference residential buildings which can be the cornerstone for prospective building regulations. Statistical analysis of available building stock data was performed to determine existing residential reference buildings. Five residential reference buildings with distinct configurations that constituted over 75% floor area share of the sampled data emerged, with floor areas varying from 191 to 1006 m2. EnergyPlus models were developed and calibrated for five residential reference buildings against yearly measured electricity consumption. Values of Mean Bias Error (MBE) and Cumulative Variation of Root Mean Squared Error CV(RMSE) between the models’ energy consumption and real energy consumption on monthly based analysis varied within the following ranges: (MBE)monthly from –0.12% to 2.01% and CV(RMSE)monthly from 1.35% to 2.96%. Thermal energy required to maintain the models' setpoint temperatures for cooling and heating varied from 6,134 to 11,451 kWh/year.

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Energy-saving potential of intermittent heating system: Influence of composite phase change wall and optimization strategy

Energy Exploration & Exploitation ◽

10.1177/0144598720969217 ◽

2020 ◽

pp. 014459872096921

Author(s):

Yanru Li ◽

Enshen Long ◽

Lili Zhang ◽

Xiangyu Dong ◽

Suo Wang

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Phase Change ◽

Air Temperature ◽

Indoor Air ◽

Thermal Environment ◽

Optimization Strategy ◽

Indoor Thermal Environment ◽

Indoor Thermal Comfort ◽

Intermittent Heating

In the Yangtze River zone of China, the heating operation in buildings is mainly part-time and part-space, which could affect the indoor thermal comfort while making the thermal process of building envelope different. This paper proposed to integrate phase change material (PCM) to building walls to increase the indoor thermal comfort and attenuate the temperature fluctuations during intermittent heating. The aim of this study is to investigate the influence of this kind of composite phase change wall (composite-PCW) on the indoor thermal environment and energy consumption of intermittent heating, and further develop an optimization strategy of intermittent heating operation by using EnergyPlus simulation. Results show that the indoor air temperature of the building with the composite-PCW was 2–3°C higher than the building with the reference wall (normal foamed concrete wall) during the heating-off process. Moreover, the indoor air temperature was higher than 18°C and the mean radiation temperature was above 20°C in the first 1 h after stopping heating. Under the optimized operation condition of turning off the heating device 1 h in advance, the heat release process of the composite-PCW to the indoor environment could maintain the indoor thermal environment within the comfortable range effectively. The composite-PCW could decrease 4.74% of the yearly heating energy consumption compared with the reference wall. The optimization described can provide useful information and guidance for the energy saving of intermittently heated buildings.

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Development of Thermal Comfort-Based Controller and Potential Reduction of the Cooling Energy Consumption of a Residential Building in Kuwait

Energies ◽

10.3390/en12173348 ◽

2019 ◽

Vol 12 (17) ◽

pp. 3348 ◽

Cited By ~ 2

Author(s):

Jaesung Park ◽

Taeyeon Kim ◽

Chul-sung Lee

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Indoor Air ◽

Residential Buildings ◽

Electric Energy ◽

Residential Building ◽

Influential Factor ◽

Electric Energy Consumption ◽

Residential Electricity ◽

The Government

In Kuwait, where the government subsidizes approximately 95% of residential electricity bills, most of the country’s energy consumption is for residential use. In particular, air-conditioning (AC) systems for cooling, which are used throughout the year, are responsible for residential electric energy consumption. This study aimed to reduce the amount of energy consumed for cooling purposes by developing a thermal comfort-based controller. Our study commenced by using a simulation model to investigate the possibility of energy reduction when using the predicted mean vote (PMV) for optimal control. The result showed that control optimization would enable the cooling energy consumption to be reduced by 33.5%. The influence of six variables on cooling energy consumption was then analyzed to develop a thermal comfort-based controller. The analysis results showed that the indoor air temperature was the most influential factor, followed by the mean radiant temperature, the metabolic rate, and indoor air velocity. The thermal comfort-based controller-version 1 (TCC-V1) was developed based on the analysis results and experimentally evaluated to determine the extent to which the use of the controller would affect the energy consumed for cooling. The experiments showed that the implementation of TCC-V1 control made it possible to reduce the electric energy consumption by 39.5% on a summer representative day. The results of this study indicate that it is possible to improve indoor thermal comfort while saving energy by using the thermal comfort-based controller in residential buildings in Kuwait.

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A review on thermal comfort, indoor air quality and energy consumption in temples

Journal of Building Engineering ◽

10.1016/j.jobe.2020.102013 ◽

2020 ◽

pp. 102013

Author(s):

Ahmet Yüksel ◽

Müslüm Arıcı ◽

Michal Krajčík ◽

Mihriban Civan ◽

Hasan Karabay

Keyword(s):

Energy Consumption ◽

Air Quality ◽

Thermal Comfort ◽

Indoor Air Quality ◽

Indoor Air

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Some flow patterns within ventilation strategy coupled to energy efficiency

The European Physical Journal Applied Physics ◽

10.1051/epjap/2019190232 ◽

2019 ◽

Vol 88 (1) ◽

pp. 10902

Author(s):

Souad Morsli ◽

Rachid Bennacer ◽

Mohammed El Ganaoui ◽

Harry Ramenah ◽

Alain Carmasol

Keyword(s):

Energy Efficiency ◽

Natural Convection ◽

Air Quality ◽

Thermal Comfort ◽

Indoor Air Quality ◽

Indoor Air ◽

Forced Flow ◽

Cooling Power ◽

Moderate Reynolds Number ◽

Mixing Ability

Energy and buildings are increasingly becoming subjects for investigations, especially for the indoor air quality domain coupled to energy demand. The physics of fluids flowing inside enclosures bring basic models to understand and build better schemes. This paper is devoted to studying ventilation strategies in regards to Indoor Air Quality (IAQ) and energy efficiency in floor refreshing houses. A room model is considered in a simplified level, as a cavity heated on the external sidewall and cooled on the bottom ground surface. The external air injector is at variable positions and interacting with the needed cooling power; the air quality (mixing ability) and thermal comfort are also studied. The cooling efficiency inside the considered volume and the average air temperature are analyzed for a given temperature difference characterizing the natural convection level (Rayleigh number, Ra = 106) and a horizontal ventilation (moderate Reynolds number Re = 102). An obtained complex flow structure indicates that the natural convection and the forced flow (ventilation) act directly on the resulting patterns, mixing ability, heat exchange which in a straight line affect the thermal comfort and in fine the energy cost (cooling requirement).

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COMPARISON OF INDOOR AIR TEMPERATURE AND OPERATIVE TEMPERATURE -DRIVEN HVAC SYSTEMS BY MEANS OF THERMAL COMFORT AND ENERGY CONSUMPTION

Mugla Journal of Science and Technology ◽

10.22531/muglajsci.679256 ◽

2020 ◽

Author(s):

Cihan TURHAN

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Air Temperature ◽

Indoor Air ◽

Hvac Systems ◽

Operative Temperature

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Analysis of Thermal Comfort and Air Quality in the Kindergarten Hart - A Case Study of a Unique Sustainable Building Design

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.887.500 ◽

2019 ◽

Vol 887 ◽

pp. 500-507

Author(s):

Matthias Schuss ◽

Mahnameh Taheri ◽

Ulrich Pont ◽

Ardeshir Mahdavi

Keyword(s):

Air Quality ◽

Thermal Comfort ◽

Indoor Air Quality ◽

Indoor Air ◽

Environmental Conditions ◽

Natural Ventilation ◽

Building Design ◽

Present Contribution ◽

Ongoing Research ◽

Indoor And Outdoor

The present contribution, reports on the results of ongoing research efforts on performance assessment of a number of buildings designed by the Austrian architect, Konrad Frey. He is a pioneer of energy-efficient architecture, and his designs, those dating back to the 1970s, adapted the principles of modern solar houses. The current study focuses on the Kindergarten Hart, which was especially designed focusing on the availability of cross ventilation option in building. For the purpose of analyzing thermal comfort, indoor air quality, and the occupants’ adaptive actions with respect to natural ventilation, we conducted long-term monitoring under summer and winter conditions. The monitoring efforts covered indoor and outdoor environmental conditions, as well as the state of windows. Thereby, study of the monitored dataset provides a better understanding of the building performance. Moreover, it makes it possible to examine whether the architect’s expectations in terms of thermal comfort and indoor air quality levels are fulfilled or not. In addition, investigation of the occupants’ interactions with windows, together with indoor and outdoor environmental conditions, assists understanding of possible associations between the window opening/closing and environmental parameters, as well as potential optimization of the control-oriented actions.

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Long-Term Assessment Methodology of Building Stock Thermal Energy Consumption

10.7250/9789934226205 ◽

2021 ◽

Author(s):

◽

Aleksejs Prozuments

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

Thermal Energy ◽

Energy Use ◽

Energy Savings ◽

Building Code ◽

Space Heating ◽

Industrial Building ◽

Building Stock

Energy efficiency in the building stock is a substantial contributor to infrastructure sustainability. In Latvia, buildings’ thermal energy use for space heating accounts for 80 % of total building energy use in the cold season. Therefore, reducing thermal energy consumption for space heating needs through the implementation of energy efficiency measures, enforcement of local building codes and regulations can ultimately lead to cost savings for building owners and stakeholders. The present PhD Thesis introduces a methodology for evaluation of thermal energy saving potential in the long run across residential, public, and industrial building stock under various thermal energy consumption compliance scenarios. These scenarios were developed based on three different building code protocols with a 10-year forecast analysis. Evaluation of the proposed building code implementation practices and their feasibility in Latvian building stock is discussed for these buildings with regards to their long-term thermal energy savings potential.

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