scholarly journals Thermal Performance and Comfort Conditions Analysis of a Vernacular Palafitic Timber Building in Portuguese Coastline Context

2020 ◽  
Vol 12 (24) ◽  
pp. 10484
Author(s):  
Jorge Fernandes ◽  
Ricardo Mateus ◽  
Helena Gervásio ◽  
Sandra Monteiro Silva ◽  
Jorge Branco ◽  
...  
Keyword(s):  
Thermal Performance ◽  
Energy Demand ◽  
Energy Performance ◽  
Subjective Analysis ◽  
Heating And Cooling ◽  
Condition Evaluation ◽  
Timber Constructions ◽  
U Value ◽  
The Difference

The palafitic timber constructions of the central Portuguese coastline are an example of the adaptation to site-specific conditions (climate and sand landscape morphodynamics) using the available endogenous resources. Thus, in a context of environmental awareness and climate change, it is relevant to understand their features/strategies and how they perform. This work analyses the energy performance and thermal condition evaluation of a vernacular timber building–palheiro–from Praia de Mira, through in situ measurements, subjective analysis and energy simulation provided by DesignBuilder/EnergyPlus. The results show a good or satisfactory thermal performance during most of the seasons by passive means only. Despite, it was not possible to guarantee thermal comfort conditions for the occupants during winter. In the energy performance analysis, five scenarios, with different external walls, were compared. In the two scenarios that satisfy the maximum U-value for the climate zone, the current conventional building had a slightly better performance on heating and cooling (less 1.1 and 1.4 kWh/m2, respectively) than the timber building. However, the difference between the two construction solutions is not substantial in the annual energy demand (2.5 kWh/m2, 7.3%), indicating that timber structures are suitable in this mild climate area.

scholarly journals Thermal Performance of Insulated Constructions—Experimental Studies

Buildings ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 49 ◽  
Author(s):  
Lars Gullbrekken ◽  
Steinar Grynning ◽  
Jørn Gaarder
Keyword(s):  
Thermal Performance ◽  
Experimental Studies ◽  
Energy Performance ◽  
High Energy ◽  
Mineral Wool ◽  
Wood Fibre ◽  
Nusselt Numbers ◽  
Performance Requirements ◽  
U Value ◽  
Passive Houses

Buildings that are designed to meet high-energy performance requirements, e.g., passive houses, require well-insulated building envelopes, with increased insulation thicknesses for roof, wall and floor structures. We investigate whether there are differences in the efficiency of thermal insulation materials at different moisture levels in the insulation and if there is a larger or smaller risk of natural convection in wood-fibre based insulation than in mineral wool. The work has mainly been performed by use of laboratory measurements included permeability properties and full-scale measurements of thermal transmittance of mineral wool and wood-fibre insulated constructions. In addition, calculations have been used to calculate resulting effects on the thermal performance of constructions. Results showed that the thermal conductivity was unaffected by moisture in the hygroscopic range. The air permeability was found to be approximately 50% higher for the wood-fibre insulation compared to mineral wool insulation. Measurements showed that the largest U-values and Nusselt numbers were found for the wall configuration. Calculation of the U-value of walls showed that in order to achieve the same U-value for the wood-fibre insulated wall as the mineral wool, it is necessary to add 20 mm insulation to the 250 mm wall and approximately 30 mm for the 400 mm wall.

scholarly journals Thermal analysis and post construction verification

2019 ◽  
Vol 38 (1) ◽  
pp. 51-67
Author(s):  
Cormac Flood ◽  
Lloyd Scott
Keyword(s):  
Case Studies ◽  
Thermal Performance ◽  
Building Materials ◽  
Energy Performance ◽  
Research Project ◽  
Content Type ◽  
Thermal Transmittance ◽  
Standard Calculation

Purpose The residential sector in Ireland accounted for 25 per cent of energy related CO2 emissions in 2016 through burning fossil fuels, a major contributor to climate change. In support of Ireland’s CO2 reduction targets, the existing housing stock could contribute greatly to the reduction of space-heating energy demand through retrofit. Approximately 50 per cent of Ireland’s 2m dwellings pre-date building regulations and are predominantly of cavity and solid wall construction, the performance of which has not been extensively investigated at present. Although commitment to thermal upgrade/retrofit of existing buildings may increase under future government policies, the poor characterisation of actual thermal performance of external walls may hinder the realisation of these targets. Thermal transmittance (U-values) of exterior walls represents a source of uncertainty when estimating the energy performance of dwellings. It has been noted in research that the standard calculation methodology for thermal transmittance should be improved. Implementing current U-value calculation methods may result in misguided retrofit strategies due to the considerable discrepancies between in situ measurements and calculated wall U-values as documented in the case studies carried out in this research. If the method of hygrothermal analysis were to be employed as a replacement for the current standard calculation, it could have significant implications for policy and retrofit decision making. The paper aims to discuss this issue. Design/methodology/approach This research project analysed a case study situated in Dublin, Ireland. The case studies offer an account of the in situ thermal transmittance of exterior walls and link these to hygrothermally simulated comparisons along with more traditional design U-values. Findings The findings of this research identify discrepancies between in situ and design U-values, using measurement, hygrothermal simulation and standard method U-value calculations. The outcomes of the research serve as an introduction to issues emanating from a larger research project in order to encourage researchers to understand and further explore the topic. Originality/value It has previously been highlighted that moisture content is linked to the increase in thermal conductivity of building materials, thus reducing the thermal effectiveness and increasing the elemental U-value. Therefore, it is vital to implement reliable prediction tools to assess potential thermal performance values. This paper presents the findings of a critical instance case study in Dublin, Ireland in which an existing west facing external wall in a semi-detached dwelling was analysed, simulated and measured to verify the elemental wall assembly and quantify thermal transmittance (U-value) incorporating the major criteria required for building performance simulation.

scholarly journals Energy Monitoring in a Heating and Cooling System in a Building Based on the Example of the Turówka Hotel

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1968 ◽  
Author(s):  
Marek Borowski ◽  
Piotr Mazur ◽  
Sławosz Kleszcz ◽  
Klaudia Zwolińska
Keyword(s):  
Energy Consumption ◽  
Energy Management ◽  
Energy Demand ◽  
Cooling System ◽  
Energy Performance ◽  
High Energy ◽  
Building Envelope ◽  
Large Variability ◽  
Heating And Cooling ◽  
And Control

The energy consumption of buildings is very important for both economic and environmental reasons. Newly built buildings are characterized by higher insulation and airtightness of the building envelope, and are additionally equipped with technologies that minimize energy consumption in order to meet legal requirements. In existing buildings, the modernization process should be properly planned, taking into account available technologies and implementation possibilities. Hotel buildings are characterized by a large variability of energy demand, both on a daily and a yearly basis. Monitoring systems, therefore, provide the necessary information needed for proper energy management in the building. This article presents an energy analysis of the Turówka hotel located in Wieliczka (southern Poland). The historical hotel facility is being modernized as part of the project to adapt the building to the requirements of a sustainable building. The modernization proposal includes a trigeneration system with a multifunctional reverse regenerator and control module using neural algorithms. The main purpose is to improve the energy efficiency of the building and adapt it to the requirements of low-energy buildings. The implementation of a monitoring system enables energy consumption to be reduced and improves the energy performance of the building, especially through using energy management systems and control modules. The proposed retrofit solution considers the high energy consumption, structure of the energy demand, and limits of retrofit intervention on façades.

scholarly journals Evaluation of Heating and Cooling Loads for a Well-Insulated Single-Family House under Variable Climate Pattern

2021 ◽  
Vol 25 (1) ◽  
pp. 750-763
Author(s):  
Aleksejs Prozuments ◽  
Arturs Staveckis ◽  
Jurgis Zemitis ◽  
Diana Bajare
Keyword(s):  
Thermal Performance ◽  
Thermal Energy ◽  
Energy Demand ◽  
Heat Waves ◽  
Reference Scenario ◽  
Single Family ◽  
Weather Patterns ◽  
Heating And Cooling ◽  
Significant Step ◽  
Family House

Abstract Single family houses consume substantially more thermal energy per floor area compared to multi-apartment buildings to satisfy space heating or cooling demand. Over the past decades there has been an undisputed evidence of a temperature rise across the world that has led to a growing concern of more extreme weather patterns and regular seasonal heat waves globally. As such, building occupants are at a continuously growing risk to overheating exposure inside the premises. Within the framework of this study a single-family house was examined with respect to its thermal performance in warm and cold seasons. A simulation model was developed in IDA-ICE software to evaluate annual thermal energy demand for a reference scenario, 3 shading scenarios and for an optimized scenario. At an optimized scenario that incorporates mechanical ventilation with a heat recovery unit and enhanced thermal performance of the external building elements, the annual thermal energy demand in the proposed single-family house was reduced by 39.5 % compared to the reference scenario, which is a significant step towards meeting nearly zero energy building criteria.

scholarly journals Coupling a Building Energy Simulation Tool with a Microclimate Model to Assess the Impact of cool Pavements on the Building’s Energy Performance. Application in a Dense Residential Area

2019 ◽  
Vol 11 (9) ◽  
pp. 2519 ◽  
Author(s):  
Tsoka ◽  
Tsikaloudaki ◽  
Theodosiou
Keyword(s):  
Urban Areas ◽  
Energy Demand ◽  
Thermal Environment ◽  
Energy Performance ◽  
Computational Method ◽  
Weather Data ◽  
Building Unit ◽  
Heating And Cooling ◽  
Data Generator ◽  
The Impact

Replacing conventional pavements with the corresponding high albedo ones constitutes a well-known technique to improve outdoor thermal environment of modern cites. Since most of the existing studies assess the impact of the high albedo pavements at the pedestrian’s height and with respect to thermal comfort, this study aims to examine the effect of the application of highly reflective pavements on the heating and cooling energy needs of a building unit, located inside a dense urban area. Aiming at a higher accuracy of the energy performance simulations, an integrated computational method between ENVI-met model, Meteonorm weather data generator and Energy Plus software is established, to consider the site-specific microclimatic characteristics of the urban areas. The analysis is performed both for the design and the aged albedo values as significant changes may occur due to aging process. The analysis revealed that the application of cool materials on the ground surfaces only marginally affects the energy performance of the examined building unit, both for the design and the aged albedo value; changes on the annual heating and cooling energy demand, for both albedo scenarios did not exceed 1.5% revealing the limited potential of cool pavements regarding the improvement of the energy performance of urban building units.

Analysis of Building Envelope Performance Effects of an Insulating Semi-Transparent Photovoltaic (STPV) Glazing Unit

2014 ◽  
Author(s):  
Dirk V. P. McLaughlin ◽  
Konstantinos Kapsis ◽  
Andreas K. Athienitis ◽  
Sam Siassi ◽  
Livio Nichilo
Keyword(s):  
Performance Standards ◽  
Energy Performance ◽  
Building Envelope ◽  
Commercial Building ◽  
Heating And Cooling ◽  
Performance Effects ◽  
Gas Consumption ◽  
U Value ◽  
And Performance ◽  
Cooling Loads

This paper presents characterization results for the electrical and thermal properties of a unique insulating semi-transparent photovoltaic (STPV) glazing unit using calorimetry hot box methods finding a U-value of 1.09 W/m2·°C and a SHGC of 0.11. These properties are then applied to an energy model of a case study commercial building in a continental climate region to examine the effects of utilizing STPV in the building envelope on the electricity and natural gas consumption levels and peak demands. The results indicate that such a building envelope can significantly reduce heating and cooling loads compared to standard glazing which would help architects maintain the desirable properties of highly glazed façades while avoiding the drop in building energy performance that could make adhering to increasingly stringent building codes and performance standards difficult. The paper also presents simulation results for the photovoltaic energy generation of the vertical STPV façades at two building orientations.

scholarly journals Energy Performance of Buildings with Thermochromic Windows in Mediterranean Climates

Energies ◽  
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.

scholarly journals Energy Efficiency Evaluation of Different Glazing and Shading Systems in a School Building

2019 ◽  
Vol 111 ◽  
pp. 03052 ◽  
Author(s):  
Mohammed Khalaf ◽  
Touraj Ashrafian ◽  
Cem Demirci
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Energy Demand ◽  
Energy Performance ◽  
Building Envelope ◽  
School Building ◽  
Total Energy Consumption ◽  
Heating And Cooling ◽  
Lighting Energy ◽  
Energy Efficiency Evaluation

The energy conversations methods and techniques take a significant role in the energy performance of the buildings. Façade and shading systems are in continuous development, and recent studies are showing the importance of implementation of such systems to reduce energy consumption and enhance the effectiveness of the building performance. School buildings are mostly being used during daytime, hence, require active use of sunlight. A measure that is taken on a school building envelope can prevent overheating and overcooling and reduce the heating and cooling energy consumption but at the same time can increase the lighting energy consumption vice versa. Thus, it is necessary to optimise the energy required for climatisation of a building with lighting energy demand. The main aim of the paper is to provide analysis for façade and shading systems applied to a school building and study the effectiveness of it on energy consumption and conservation. The case study for this paper is a typical building project designed to be located in Istanbul, Turkey and has a traditional façade system which is clear double layer windows without any shading devices. The analyses of the energy efficiency of these systems will be presented. The different glazing types and shading systems alternatives will show the most efficient one to be used as some optimised alternatives for the systems. Findings indicate that proper glazing and shading systems can reduce the needed energy for heating and lightening and thus total energy consumption of a school building significantly.

scholarly journals A Methodology to Investigate the Deviations between Simple and Detailed Dynamic Methods for the Building Energy Performance Assessment

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6217
Author(s):  
Ilaria Ballarini ◽  
Andrea Costantino ◽  
Enrico Fabrizio ◽  
Vincenzo Corrado
Keyword(s):  
Energy Demand ◽  
Dynamic Models ◽  
Building Energy ◽  
Energy Performance ◽  
Transfer Coefficients ◽  
Study Approach ◽  
Heat Transfer Coefficients ◽  
Heating And Cooling ◽  
Cooling Loads ◽  
Physical Phenomena

The research investigates the validity of the simple hourly method, as introduced by the EN ISO 52016-1 standard, for the assessment of the building energy demand for heating and cooling, by comparing it with a detailed dynamic model (EnergyPlus). A new methodology is provided to identify and quantify the causes of deviations between the models. It consists in the split of the contributions of the air heat balance (AHB) equation by dynamic driving force, and in the adoption of consistency options of the modeling parameters related to specific physical phenomena. A case study approach is adopted in the article to achieve the research objective. The results show that the deviations in the heating and cooling loads between the two calculation methods can be mainly ascribed to the use of different surface heat transfer coefficients, and to a different modeling of the extra thermal radiation to the sky. Providing a methodology to validate the calculation method, this work is intended to contribute to the enhancement of the use of simple dynamic models and to the improvement of the standardization activity.

scholarly journals In Situ Evaluation of the U-Value of a Window Using the Infrared Method

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1904
Author(s):  
Seyoung Park ◽  
Seo Hoon Kim ◽  
Hakgeun Jeong ◽  
Sung Lok Do ◽  
Jonghun Kim
Keyword(s):  
Thermal Performance ◽  
Measurement Method ◽  
Performance Test ◽  
Thermal Characteristics ◽  
Energy Performance ◽  
Existing Building ◽  
Design Values ◽  
Improvement Method ◽  
Infrared Method ◽  
U Value

The amount of heat lost through the envelope of a building is one of the most important variables that affects the energy performance evaluation of a house. In addition, it is especially important to estimate and accurately diagnose the amount of heat produced by windows. In Korea, windows’ U-values reflect a building’s initial design values and thermal characteristics that determine the thermal performance of an existing building, and is a factor that can overestimate the energy performance of a building. Therefore, there is a need for a field measurement method that can accurately measure the total U-value of windows in an existing house. This study provides a method of quantitatively measuring the total U-value of windows using the infrared (IR) method in ISO 9869-2. As a result of measuring the U-value using the infrared (IR) method, the Korean Standard (KS F 2278) for window performance test result values and the root mean square error (cvRMSE) for the U-value measurements using the IR method showed a high accuracy of about 3.29%. In addition, we confirmed that the IR method is an effective (cvRMSE about 7% improvement) method that can measure the comparison result faster than the heat flow meter (HFM) method, which is a conventional thermal performance measurement method.

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