The role of Thermally Activated Building Systems (TABS) in building energy retrofitting: energy diagnosis and management

Thermally Activated Building Systems (TABS) play a major role in building envelope integration. TABS operate at low temperatures, enabling efficient utilization of renewable sources. Moreover, their combination with other building energy systems provides a high degree of dynamic interactivity with users, improving the quality of the indoor thermal environment. In this research, the efficiency of the technology of active pipe-embedded structures is investigated within its practical application in an existing office building energy retrofit in Spain. Concrete Core Activation (CCA) of the original horizontal structure aims at exploiting its thermal inertial properties and potential storage capability in combination with low-grade energy production systems and devices, such as geothermal heat pumps. A proper methodology of energy diagnosis is aimed at the optimization of TABS performance in building retrofitting. Significant energy savings could be achieved by applying appropriate solutions, control strategies and corrective actions for TABS. The continuity of energy management and follow-up has been proven necessary to keep high standards in terms of TABS energy performance, targeting the identification of energy saving opportunities for the improvement of energy efficiency.

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The determination of the thermal reliability criterion for building envelope structures

Tehnički glasnik ◽

10.31803/tg-20181123111226 ◽

2019 ◽

Vol 13 (2) ◽

pp. 129-133

Author(s):

Gennadiy Farenyuk

Keyword(s):

Thermal Insulation ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Time Analysis ◽

Thermal Reliability ◽

Thermal Failure ◽

Reliability Criterion ◽

Building Operation

The paper presents the basic methodical principles for the time analysis of the variations of envelope structures’ thermal insulation properties and for the substantiation of the thermal reliability criterion, which should allow the analysis of the actual parameters of heat losses during the operation of buildings. In the paper, the state of the envelope structures thermal failure, the concept of building thermal envelope thermal reliability and the principles of its rating are defined. The physical meaning and basic criterion of the envelope structure thermal reliability are formulated. The application of the thermal reliability criterion allows determining the probable variations in the thermal insulation properties during the building operation and, accordingly, the changes of the building energy performance over time.

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Application of Urban Scale Energy Modelling and Multi-Objective Optimization Techniques for Building Energy Renovation at District Scale

Sustainability ◽

10.3390/su132011554 ◽

2021 ◽

Vol 13 (20) ◽

pp. 11554

Author(s):

Fahad Haneef ◽

Giovanni Pernigotto ◽

Andrea Gasparella ◽

Jérôme Henri Kämpf

Keyword(s):

Energy Efficiency ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Optimization Techniques ◽

Multi Objective Optimization ◽

Building Stock ◽

Energy Efficiency Measures ◽

Multi Objective ◽

Efficiency Measures

Nearly-zero energy buildings are now a standard for new constructions. However, the real challenge for a decarbonized society relies in the renovation of the existing building stock, selecting energy efficiency measures considering not only the energy performance but also the economic and sustainability ones. Even if the literature is full of examples coupling building energy simulation with multi-objective optimization for the identification of the best measures, the adoption of such approaches is still limited for district and urban scale simulation, often because of lack of complete data inputs and high computational requirements. In this research, a new methodology is proposed, combining the detailed geometric characterization of urban simulation tools with the simplification provided by “building archetype” modeling, in order to ensure the development of robust models for the multi-objective optimization of retrofit interventions at district scale. Using CitySim as an urban scale energy modeling tool, a residential district built in the 1990s in Bolzano, Italy, was studied. Different sets of renovation measures for the building envelope and three objectives —i.e., energy, economic and sustainability performances, were compared. Despite energy savings from 29 to 46%, energy efficiency measures applied just to the building envelope were found insufficient to meet the carbon neutrality goals without interventions to the system, in particular considering mechanical ventilation with heat recovery. Furthermore, public subsidization has been revealed to be necessary, since none of the proposed measures is able to pay back the initial investment for this case study.

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PERFORMANCE INDICATORS FOR ENERGY EFFICIENCY RETROFITTING IN MULTIFAMILY RESIDENTIAL BUILDINGS

Journal of Green Building ◽

10.3992/1943-4618.14.2.109 ◽

2019 ◽

Vol 14 (2) ◽

pp. 109-136

Author(s):

Chaitali Basu ◽

Virendra Kumar Paul ◽

M.G. Matt Syal

Keyword(s):

Energy Efficiency ◽

Performance Assessment ◽

Performance Indicators ◽

Residential Buildings ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Assessment Process ◽

Second Phase ◽

A Priority

The energy performance of an existing building is the amount of energy consumed to meet various needs associated with the standardized use of a building and is reflected in one or more indicators known as Building Energy Performance Indicators (EnPIs). These indicators are distributed amongst six main factors influencing energy consumption: climate, building envelope, building services and energy systems, building operation and maintenance, occupants' activities and behaviour, and indoor environmental quality. Any improvement made to either the existing structure or the physical and operational upgrade of a building system that enhances energy performance is considered an energy efficiency retrofit. The main goal of this research is to support the implementation of multifamily residential building energy retrofits through expert knowledge consensus on EnPIs for energy efficiency retrofit planning. The research methodology consists of a comprehensive literature review which has identified 35 EnPIs for assessing performance of existing residential buildings, followed by a ranking questionnaire survey of experts in the built-environment to arrive at a priority listing of indicators based on mean rank. This was followed by concordance analysis and measure of standard deviation. A total of 280 experts were contacted globally for the survey, and 106 completed responses were received resulting in a 37.85% response rate. The respondents were divided into two groups for analysis: academician/researchers and industry practitioners. The primary outcome of the research is a priority listing of EnPIs based on the quantitative data from the knowledge-base of experts from these two groups. It is the outcome of their perceptions of retrofitting factors and corresponding indicators. A retrofit strategy consists of five phases for retrofitting planning in which the second phase comprises an energy audit and performance assessment and diagnostics. This research substantiates the performance assessment process through the identification of EnPIs.

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Thermal Imaging for Detection of Defects in Envelopes of Buildings in Use: Qualitative and Quantitative Analysis of Building Energy Performance

Periodica Polytechnica Civil Engineering ◽

10.3311/ppci.12148 ◽

2018 ◽

Cited By ~ 1

Author(s):

Anna Ostańska

Keyword(s):

Quantitative Analysis ◽

Thermal Imaging ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Qualitative And Quantitative Analysis ◽

Infrared Images ◽

Building Energy Performance ◽

Qualitative And Quantitative ◽

Energy Performance Of Buildings

The proposed interdisciplinary method of identifying defects in the building envelope insulation enables the user to quickly assess the scale of heat loss problems in occupied buildings. The method rests upon the quantitative analysis of macroscopic infrared images of the buildings. The method was applied in practice to assess effects of thermal upgrade project in Dźbów housing estate in Częstochowa, a city located in southern Poland. The results confirmed the applicability of the method to monitoring energy performance of buildings in use without intervention into the building’s fabric and without disturbing the occupants.

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Building energy modelling for the energy performance analysis of a hospital building in various locations

E3S Web of Conferences ◽

10.1051/e3sconf/201911106073 ◽

2019 ◽

Vol 111 ◽

pp. 06073 ◽

Cited By ~ 1

Author(s):

Ioan Silviu Dobosi ◽

Cristina Tanasa ◽

Nicoleta-Elena Kaba ◽

Adrian Retezan ◽

Dragos Mihaila

Keyword(s):

European Union ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

The European Union ◽

Total Energy Consumption ◽

Building Stock ◽

Heating And Cooling ◽

Key Factor ◽

Hospital Building

The building sector has been identified as having the greatest energy reduction potential and therefore represents a key factor for the European Union climate change combat objectives of achieving an 80-95% greenhouse gas emissions reduction by 2050. Hospitals buildings represent 7% of the nonresidential building stock in the European Union and are responsible for approximately 10% of the total energy consumption in this sector. The design and construction of hospital buildings is a complex and challenging activity for all the involved specialists, especially when energy performance is one of the objectives. This paper discusses the energy performance simulation on an hourly basis of a new hospital building that was constructed in the city of Mioveni, Romania. At this stage of the study, the building energy model solely investigates the performance of the building envelope, without modelling the HVAC system. The complexity of the building model derives from the multitude of thermal zones depending on interior temperature and ventilation air changes conditions. Several simulations are performed investigating the heating and cooling energy need depending on the building location.

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Design of A GUI Tool for the Prediction of Building Energy Performance

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.29-32.2789 ◽

2010 ◽

Vol 29-32 ◽

pp. 2789-2793

Author(s):

Cheng Wen Yan ◽

Jian Yao ◽

Jin Xu

Keyword(s):

Bp Neural Network ◽

Energy Efficient ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Building Energy Efficiency ◽

Building Energy Performance ◽

Mathematical Equations ◽

Building Physics ◽

Energy Efficient Building

In the present study a GUI tool for the prediction of building energy performance based on a three-layered BP neural network and MATLAB was developed. The inputs for this tool are the 18 building envelope parameters. The outputs are building heating, cooling and total energy consumptions and the energy saving rate. Compared with the complicated mathematical equations, this tool provides a very easy and effective method for students to learn the effects of building envelope performance parameters on the building energy performance. Thus, this tool can be used in building physics and building energy efficiency courses for the design of energy efficient building.

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Impact of orientation and building envelope characteristics on energy consumption case study of office building in city of Nis

Thermal Science ◽

10.2298/tsci18s5499v ◽

2018 ◽

Vol 22 (Suppl. 5) ◽

pp. 1499-1509

Author(s):

Miomir Vasov ◽

Jelena Stevanovic ◽

Veliborka Bogdanovic ◽

Marko Ignjatovic ◽

Dusan Randjelovic

Keyword(s):

Energy Consumption ◽

Early Stage ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Office Building ◽

Climatic Data ◽

Building Energy Efficiency ◽

Maximum Difference ◽

Heating And Cooling

Buildings are one of the biggest energy consumers in urban environments, so its efficient use represents a constant challenge. In public objects and households, a large part of the energy is used for heating and cooling. The orientation of the object, as well as the overall heat transfer coefficient (U-value) of transparent and non-transparent parts of the envelope, can have a significant impact on building energy needs. In this paper, analysis of the influence of different orientations, U-values of envelope elements, and size of windows on annual heating and cooling energy for an office building in city of Nis, Serbia, is presented. Model of the building was made in the Google SketchUp software, while the results of energy performance were obtained using EnergyPlus and jEplus, taking into ac-count the parameters of thermal comfort and climatic data for the area of city of Nis. Obtained results showed that, for varied parameters, the maximum difference in annual heating energy is 15129.4 kWh, i. e per m2 27.75 kWh/m2, while the maximum difference in annual cooling energy is 14356.1 kWh, i. e per m2 26.33 kWh/m2. Considering that differences in energy consumption are significant, analysis of these parameters in the early stage of design process can affect on increase of building energy efficiency.

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Comparison between Energy Simulation and Monitoring Data in an Office Building

Energies ◽

10.3390/en15010239 ◽

2021 ◽

Vol 15 (1) ◽

pp. 239

Author(s):

Koldobika Martin-Escudero ◽

Garazi Atxalandabaso ◽

Aitor Erkoreka ◽

Amaia Uriarte ◽

Matteo Porta

Keyword(s):

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Energy Simulation ◽

Office Building ◽

Mean Bias Error ◽

Bias Error ◽

Data Sets ◽

Hourly Basis ◽

Good Agreement

One of the most important steps in the retrofitting process of a building is to understand its pre-retrofitting stage energy performance. The best choice for carrying this out is by means of a calibrated building energy simulation (BES) model. Then, the testing of different retrofitting solutions in the validated model allows for quantifying the improvements that may be obtained, in order to choose the most suitable solution. In this work, based on the available detailed building drawings, constructive details, building operational data and the data sets obtained on a minute basis (for a whole year) from a dedicated energy monitoring system, the calibration of an in-use office building energy model has been carried out. It has been possible to construct a detailed white box model based on Design Builder software. Then, comparing the model output for indoor air temperature, lighting consumption and heating consumption against the monitored data, some of the building envelope parameters and inner building inertia of the model were fine tuned to obtain fits fulfilling the ASHRAE criteria. Problems found during this fitting process and how they are solved are explained in detail. The model calibration is firstly performed on an hourly basis for a typical winter and summer week; then, the whole year results of the simulation are compared against the monitored data. The results show a good agreement for indoor temperature, lighting and heating consumption compared with the ASHRAE criteria for the mean bias error (MBE).

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Solar gain mitigation in ventilated tiled roofs by using phase change materials

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctaa001 ◽

2020 ◽

Vol 15 (3) ◽

pp. 434-442

Author(s):

Michele Bottarelli ◽

Francisco Javier González Gallero ◽

Ismael Rodríguez Maestre ◽

Gang Pei ◽

Yuehong Su

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Dynamics Model ◽

Night Time ◽

Low Wind Speed ◽

Cooling Design ◽

Hot Season

Abstract Several passive cooling design techniques are known for reducing solar heat gain through building envelope in summer season. These include the use of phase change materials (PCM), which has received an increased attention over the last years, and the strategy of increasing the above-sheathing ventilation (ASV) in ventilated roofs. However, few studies combine both technologies to maximise the building resilience in hot season. The effect of including a PCM layer into a ventilated roof is numerically analysed here in two different configurations: firstly, laid on the roof deck (PCM1 case) and, secondly, suspended in the middle of the ASV channel (PCM2 case). A computational fluid dynamics model was implemented to simulate airflow and heat transfer around and through the building envelope, under 3 days of extreme hot conditions in summer with high temperatures and low wind speed. Results showed slight differences in terms of mean temperatures at the different roof layers, although temperature fluctuations at deck in the PCM1 case were smaller than half of those estimated for the benchmark case. However, PCM2 configuration achieved a daily reduction of about 10 Wh/m2 (18%) in building energy load with respect to the benchmark case, whilst PCM1 got only 4% due to the lower ventilation at night time. Therefore, a suspended PCM layer in the ASV channel would be a better measure in terms of energy performance than laid on the deck surface, although this last option significantly decreases thermal stress of the insulation layer.

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