Field assessment of thermal comfort conditions and energy performance of social housing: The case of hot summers in the Mediterranean climate

Natural ventilation through window openings is an inexpensive and effective solution to bring fresh air into internal spaces and improve indoor environmental conditions. This study attempts to address the “indoor air quality–thermal comfort” dilemma of naturally ventilated office buildings in the Mediterranean climate through the effective use of early window design. An experimental method of computational modelling and simulation was applied. The assessments of indoor carbon dioxide (CO2) concentration and adaptive thermal comfort were performed using the British/European standard BS EN 15251:2007. The results indicate that when windows were opened, the first-floor zones were subjected to the highest CO2 levels, especially the north-facing window in the winter and the south-facing window in the summer. For a fully glazed wall, a 10% window opening could provide all the office hours inside category I of CO2 concentration. Such an achievement requires full and quarter window openings in the cases of 10% and 25% window-to-floor ratios (WFR), respectively. The findings of the European adaptive comfort showed that less than 50% of office hours appeared in category III with cross-ventilation. The concluding remarks and recommendations are presented.

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DSF studies towards energy efficiency for a tall building design in the Mediterranean climate

iCRBE Procedia ◽

10.32438/icrbe.202026 ◽

2020 ◽

pp. 165-179

Author(s):

T Saroglou ◽

T Theodosiou ◽

I. A. Meir

Keyword(s):

Energy Efficiency ◽

Thermal Comfort ◽

Energy Efficient ◽

Mediterranean Climate ◽

Tall Buildings ◽

Building Design ◽

High Energy ◽

Tall Building ◽

Energy Demands ◽

The Mediterranean

Tall buildings around the world are increasing at an accelerating pace. However, this fast-pace development is not in tandem with today’s environmental considerations towards reducing high carbon emissions, mainly relating to the building sector (close to 50% of carbon dioxide (CO2) emissions). The vast scale and energy demands of tall buildings call for an in-depth study of this building typology towards improving energy efficiency. An important consideration for lowering energy demands is the configuration of the building envelope that acts as the mediator between indoor and outdoor conditions, according to the climate and microclimate of the building’s location. Current architectural practices of fully glazed curtain wall envelopes make this relationship problematic, by resulting in high-energy loads for achieving thermal comfort. Over the last few years, a step forward towards energy efficiency is the use of a double-skin façade (DSF). Its application, however, is lacking consideration of the specific climatic conditions that will essentially result in an energy efficient design. Previous research revealed that the most energy efficient DSF in the Mediterranean climate is with LowE glazing as the outside DSF layer. Further studies on DSF cavity width for a hot climate, were in favour of wider cavities, as these reduce the high cooling loads that are associated with this climate. Additionally, simulations of an office building in the Mediterranean climate, confirmed that cooling energy is also present during winter (airtight DSF), suggesting for a more active DSF envelope design throughout the year. A further study is then conducted through simulations, where the DSF design alternates between an open / closed DSF, and comparisons are made in relation to DSF width, building height above ground, outdoor environmental conditions and interior thermal comfort, for further improving the energy efficiency of tall building design.

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Energy Performance of Buildings with Thermochromic Windows in Mediterranean Climates

Energies ◽

10.3390/en14216977 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6977

Author(s):

Georgios E. Arnaoutakis ◽

Dimitris A. Katsaprakakis

Keyword(s):

Energy Demand ◽

Mediterranean Climate ◽

Three Dimensional ◽

Energy Performance ◽

Information Modeling ◽

High Resolution Data ◽

Energy Performance Of Buildings ◽

Heating And Cooling ◽

The Mediterranean ◽

Comparative Results

This article presents comparative results on the energy performance of buildings in the Mediterranean. Many buildings in the Mediterranean exhibit low energy performance ranking. Thermochromic windows are able to improve the energy consumption by controlling the gains from sunlight. In this article, reference buildings in 15 cities around the Mediterranean are investigated. In this work, a dynamic building information modeling approach is utilized, relying on three-dimensional geometry of office buildings. Calculations of the energy demand based on computational simulations of each location were performed, for the estimation of heating and cooling loads. The presented study highlighted the need for high-resolution data for detailed simulation of thermochromic windows in buildings of Mediterranean cities. Temperature is one of the main climate parameters that affect the energy demand of buildings. However, the climate of Mediterranean cities nearby the sea may affect the energy demand. This was more pronounced in cities with arid Mediterranean climate with increased demand in air-conditioning during the summer months. On the other hand, cities with semi-arid Mediterranean climate exhibited relatively increased heating demand. With this parametric approach, the article indicates the energy saving potential of the proposed measures for each Mediterranean city. Finally, these measures can be complemented by overall building passive and active systems for higher energy reductions and increased comfort.

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Assessment of the Inner Skin Composition Impact on the Double-skin Façade Energy Performance in the Mediterranean Climate

Energy Procedia ◽

10.1016/j.egypro.2017.03.021 ◽

2017 ◽

Vol 111 ◽

pp. 195-204 ◽

Cited By ~ 6

Author(s):

Ines Khalifa ◽

Leila Gharbi-Ernez ◽

Essia Znouda ◽

Chiheb Bouden

Keyword(s):

Mediterranean Climate ◽

Energy Performance ◽

Double Skin ◽

The Mediterranean

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Thermal Comfort Improvement for Atrium Building with Double-Skin Skylight in the Mediterranean Climate

Sustainability ◽

10.3390/su12062253 ◽

2020 ◽

Vol 12 (6) ◽

pp. 2253

Author(s):

Refaa Sokkar ◽

Halil Z. Alibaba

Keyword(s):

Thermal Comfort ◽

Thermal Performance ◽

Mediterranean Climate ◽

Working Hours ◽

Economic Benefits ◽

Climatic Conditions ◽

Design Strategies ◽

Double Skin ◽

The Mediterranean ◽

American Society

Atria are added to buildings for their aesthetical, environmental, and economic benefits; the appropriate atrium design can enhance an atrium’s thermal performance and the adjacent spaces’ temperatures. However, inappropriate design decisions cause thermal discomfort and consequently, higher energy consumption. Since the Mediterranean climate has diverse climatic conditions around the year, a central atrium with a top-lit skylight is recommended, but during the summer period it can cause overheating, and the insertion of shading elements shrinks the lighting performance: thus, the atrium skylight design is supposed to improve thermal comfort without affecting the lighting level. This study investigated the improvement of thermal performance in the atrium building by the implementation of a double-skin skylight (DSS) to enhance the atrium thermal performance without shading. The research conducted computer simulations with Environmental Design Solutions (EDSL) Tas software sequentially. The study prepared various design strategies, and different proposals were tested and compared in terms of indoor temperatures, with reference to American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE-55). The implementation of DSS achieved an average of 77% comfort in working hours around the year with different opening percentages according to the outdoor conditions. Moreover, results show that changing the DSS glazing materials did not affect the thermal performance of the atrium.

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Evaluation of Thermal Comfort Performance of a Vertical Garden on a Glazed Façade and its Effect on Building and Urban Scale, Case Study: An Office Building in Barcelona

Sustainability ◽

10.3390/su13126706 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6706

Author(s):

Faezeh Bagheri Moghaddam ◽

Josep Maria Fort Mir ◽

Isidro Navarro Delgado ◽

Ernesto Redondo Dominguez

Keyword(s):

Thermal Comfort ◽

Thermal Performance ◽

Indoor Air ◽

Mediterranean Climate ◽

Office Building ◽

Glazed Facade ◽

The Mediterranean ◽

Indoor Comfort ◽

Vegetation Layer

The aim of this paper is to investigate the thermal performance of vertical gardens by comparing the thermal comfort of bare (glazed) and green façades in the Mediterranean climate. The proposal consists of applying a vegetation layer on a glazed façade that could control solar radiation and reduce indoor air temperatures. This study investigates the thermal performance of green façades of an office building in the Mediterranean climate. For this purpose, the Gas Natural Fenosa Office Building as a case study was simulated, that is located on a site next to the coastline in Barcelona. Dynamic building energy simulation was used to determine and assess indoor thermal conditions and, for this reason, the IES VE as a simulation tool has been utilized. Thermal comfort was assessed through the adaptive comfort approach and results were analyzed and presented in the terms of indoor comfort conditions during occupied hours. As a result, the article shows that applying a green façade as a vegetation layer caused a reduction in the internal and external façade surface temperatures, as well as the indoor air temperature of the workplace. Additionally, enhancing indoor comfort in summer is closely associated with reducing the external surface temperature. In winter, it also protects the exterior surface from the low temperature of the outside, and all of this greatly increases thermal comfort performance.

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Thermal Comfort and Energy Performance of Atrium in Mediterranean Climate

Sustainability ◽

10.3390/su11041213 ◽

2019 ◽

Vol 11 (4) ◽

pp. 1213 ◽

Cited By ~ 2

Author(s):

Reihaneh Aram ◽

Halil Alibaba

Keyword(s):

Thermal Comfort ◽

Heat Loss ◽

Mediterranean Climate ◽

Warm Season ◽

Energy Performance ◽

Cold Season ◽

The Other ◽

Office Building ◽

Building Model ◽

Window Opening

This paper aims to determine the optimal single-story office building model with a corner atrium regarding different atrium orientations and office-building window-opening ratios in the Mediterranean climate via EDSL Tas software. When window-opening ratios were 25% and 50% at the northeast and southeast orientations of atriums and office spaces, thermal comfort was achieved according to categories B and C, respectively, within the cold season. Additionally, for the northeast atrium orientation with 25%, 137.2 W and 189.5 W of heat loss and gain in the office zone, and 37.7 W and 204.7 W of heat loss and gain in the atrium zone were recorded. Moreover, for the northeast atrium orientation with 50%, 134.5 W and 134.2 W of heat loss and gain in the office zone, and 40 W and 192 W of heat loss and gain in the atrium zone were recorded. On the other hand, for the southeast atrium orientation with 25%, 108.7 W and 143 W of heat loss and gain in the office zone, and 68.8 W and 130 W of heat loss and gain in the atrium zone were recorded, while, with 50%, 111.7 W and 142.7 W of heat loss and gain in the office zone, and 67.5 W and 121.2 W of heat loss and gain in the atrium zone were recorded. In the warm season, the atrium and office spaces were not thermally comfortable.

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Analysis of the energy performance strategies of school buildings site in the Mediterranean climate: A case study the schools of Matera city

Energy and Buildings ◽

10.1016/j.enbuild.2017.07.018 ◽

2017 ◽

Vol 152 ◽

pp. 52-60 ◽

Cited By ~ 18

Author(s):

Gianluca Rospi ◽

Nicola Cardinale ◽

Francesca Intini ◽

Elisabetta Negro

Keyword(s):

Mediterranean Climate ◽

Energy Performance ◽

School Buildings ◽

The Mediterranean ◽

Performance Strategies

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Dynamic Evaluation of Heat Thefts Due to Different Thermal Performances and Operations between Adjacent Dwellings

Applied Sciences ◽

10.3390/app10072436 ◽

2020 ◽

Vol 10 (7) ◽

pp. 2436

Author(s):

Laura Canale ◽

Vittoria Battaglia ◽

Giorgio Ficco ◽

Giovanni Puglisi ◽

Marco Dell’Isola

Keyword(s):

Energy Consumption ◽

Thermal Comfort ◽

Social Housing ◽

Mediterranean Climate ◽

Heating System ◽

Heat Flows ◽

Central Heating ◽

Consumption Data ◽

Different Temperatures

Apartment position and operation within buildings play a significant role on energy consumption and also on perceived thermal comfort. Dwellings with favorable positions can have significant benefit, also when heated for a limited number of hours, if compared to apartments located in disadvantaged positions (i.e., upper or lower floors or north-oriented). This may be the cause of debates, especially in buildings with central heating, when heat costs are shared among tenants by means of sub-metering systems. In this paper, authors address this issue by studying the “heat thefts” phenomenon in dynamic conditions in a low-insulated building, when the heating system is used unevenly by the tenants (i.e., with different temperatures and/or use). To this end, a social housing building located in Mediterranean climate, where daily temperature excursions and solar heat gains enhance the dynamics of the heat flows, has been chosen as the case-study. The real operation of the building has been simulated in different operational scenarios and the model has been validated against energy consumption data collected experimentally. Results confirm that special allocation and or/compensation strategies should be taken in heat costs allocation in order to avoid accentuating situations of inequalities, especially in low-insulated and/or occasionally heated buildings.

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