scholarly journals Modeling of an Aerogel-Based “Thermal Break” for Super-Insulated Window Frames

Buildings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 60 ◽  
Author(s):  
Alessandro Cannavale ◽  
Francesco Martellotta ◽  
Umberto Berardi ◽  
Chiara Rubino ◽  
Stefania Liuzzi ◽  
...  

Research activities in the field of innovative fixtures are continuously aiming at increasing their thermal and optical performances to offer optimal exploitation of daylight and solar gains, providing effective climate screen, according to increasing standards for indoor comfort and energy saving. Within this work, we designed an innovative aerogel-based “thermal break” for window frames, so as to consistently reduce the frame conductance. Then, we compared the performance of this new frame both with currently used and obsolete frames, present in most of the existing building stock. Energy savings for heating and cooling were assessed for different locations and confirmed the potential role played by super-insulating materials in fixtures for extremely rigid climates.

Author(s):  
Heangwoo Lee ◽  
Xiaolong Zhao ◽  
Janghoo Seo

Recent studies on light shelves found that building energy efficiency could be maximized by applying photovoltaic (PV) modules to light shelf reflectors. Although PV modules generate a substantial amount of heat and change the consumption of indoor heating and cooling energy, performance evaluations carried out thus far have not considered these factors. This study validated the effectiveness of PV module light shelves and determined optimal specifications while considering heating and cooling energy savings. A full-scale testbed was built to evaluate performance according to light shelf variables. The uniformity ratio was found to improve according to the light shelf angle value and decreased as the PV module installation area increased. It was determined that PV modules should be considered in the design of light shelves as their daylighting and concentration efficiency change according to their angles. PV modules installed on light shelves were also found to change the indoor cooling and heating environment; the degree of such change increased as the area of the PV module increased. Lastly, light shelf specifications for reducing building energy, including heating and cooling energy, were not found to apply to PV modules since PV modules on light shelf reflectors increase building energy consumption.


2014 ◽  
Vol 39 (2) ◽  
pp. 48-56
Author(s):  
Tadeo Baldiri Salcedo Rahola ◽  
Ad Straub ◽  
Angela Ruiz Lázaro ◽  
Yves Galiègue

The renovation of existing building stock is seen as one the most practical ways to achieve the high energy savings targets for the built environment defined by European authorities. In France, the Grenelle environmental legislation addresses the need to renovate the building stock and specifically stresses the key role of social housing organisations. In recent years, French procurement rules have been modified in order to allow social housing organisations to make use of integrated contracts such as Design-Build-Maintain. These contracts have a greater potential to deliver energy savings in renovation projects than do traditional project delivery methods, like Design-bid-Build. This is because they facilitate collaboration between the various actors and boost their commitment to the achievement of project goals. In order to evaluate the estimated potential of such contracts to achieve energy savings, two renovation projects (carried out by two French social housing organisations) were analysed from their inception until the end of construction work. The analysis is based on written tender documents, technical evaluation reports, observations of the negotiation phase (in one of the cases) and interviews with the main actors involved. Findings show that Design-Build-Maintain contracts do indeed offer substantial energy savings. Both projects achieved higher energy targets than those initially required. Furthermore, the energy results are guaranteed by the contractor, through a system of bonuses and penalties. Other results demonstrate that, compared to previous Design-bid-Build renovation projects, these projects were completed in less time (from project inception to completion of the work) and at virtually the same cost. There has also been a substantial improvement in cooperation between the actors involved.


2019 ◽  
Vol 111 ◽  
pp. 04036
Author(s):  
Sebastian Wolf ◽  
Maria Justo Alonso ◽  
Davide Calì ◽  
John Krogstie ◽  
Hans Martin Mathisen ◽  
...  

In the existing building stock, heating, cooling and ventilation often run on fixed schedules assuming maximal occupancy. However, fitting the control of the HVAC system to the building’s real demand offers large potential for energy savings over the status quo. Building occupants’ presence as well as mechanically supplied and infiltrated airflow rates provide information that enables to define tailored strategies for demand-controlled ventilation. Hence, real-time estimations of these quantities are a valuable input to demand-controlled built environments. In this work, the use of stochastic differential equations (SDE) to estimate the room occupancy, infiltration air-rate and ventilation air-rate is investigated. In particular, a grey-box model based on a carbon dioxide (CO2) mass balance equation is presented. The model combines knowledge about the physical system with statistical, data-driven parameter estimation. Furthermore, the proposed model contains uncertainty parameters. This is in contrast to purely deterministic models based on ordinary differential equations, where uncertainty is usually disregarded. The suggested model has been tested in a naturally ventilated and in a mechanically ventilated environment; the performance in these two cases has been compared. We show that the ability to address measurement errors and non-homogeneous conditions in the room air implies that the suggested SDE-based grey-box approach is suitable in the context of demand-controlled ventilation.


2021 ◽  
Vol 312 ◽  
pp. 06003
Author(s):  
Franz Bianco Mauthe Degerfeld ◽  
Ilaria Ballarini ◽  
Giovanna De Luca ◽  
Vincenzo Corrado

The EN ISO 52016-1 standard presents a new simplified dynamic calculation procedure, whose aim is to provide an accurate energy performance assessment without excessively increasing the number of data required. The Italian National Annex to EN ISO 52016-1, currently under development, provides some improvements to the hourly calculation method; despite many works can be found in literature on the hourly model of EN ISO 52016-1, the National Annexes application has not been sufficiently analysed yet. The aim of the present work is to assess the main improvements introduced by the Italian National Annex and to compare the main results, in terms of energy need for space heating and cooling. To this purpose, an existing building representative of the Italian office building stock in Northern Italy was selected as a case study. The energy simulations were carried out considering both continuous and reduced operation of the HVAC systems. The options specified in the Italian National Annex were firstly applied one by one, and then all together. The variation of the energy need compared to the international base procedure is finally quantified. For the premises and the scope above discussed, the present work is intended to enhance the standardisation activity towards the adoption of more accurate and trustable calculation methods of the building energy performance.


Author(s):  
Nermina Zagora ◽  
Mladen Burazor ◽  
Erdin Salihović

This paper intends to bring attention of both scientific and general audience to the status quo of the existing, residential building stock in Bosnia and Herzegovina, highlighting its energy savings potential. The research results presented in this text may be applicable on two levels: on a larger scale, the policy makers may use this data in the process of development of strategic and EE measures implementation plans, while, on a smaller scale, the individual users may gain practical insight into the benefits of energy saving measures and implement them in their own households. Moreover, the exposed data may be subject to further evaluations, studies and comparisons, while the presented methodology can be used by other researchers in countries where there have not been research activities on the existing residential buildings stock from the EE perspective.


2021 ◽  
Author(s):  
J. J. McArthur ◽  
Chris Jofeh ◽  
Ann-Marie Aguilar

There is increasing literature demonstrating the link between building indoor environmental quality, and occupant health and productivity, driving the corporate real estate industry to investigate how to integrate wellness features in both new and existing building stock. Meanwhile, new voluntary standards to promote occupant health are becoming adopted alongside sustainability standards. As commercial building owners and tenants seek to improve occupant conditions and incorporate wellness, apparently conflicting priorities must be balanced, particularly improving indoor environmental conditions has the potential to increase energy. This paper presents a framework to consider retrofits holistically and considering the benefit of improved conditions both qualitatively and quantitatively. Where poor conditions exist, published literature demonstrates a lost productivity cost that exceeds typical building energy costs, and this is quantified in the financial analysis presented. Energy retrofits provide a unique opportunity to integrate wellness-enabling features because the energy savings can offset marginal energy or operating cost increases for particular wellness interventions. This paper presents a flexible, customizable framework to develop potential retrofit bundles and evaluate them considering economic, sustainability, wellness, risk and occupant experience factors to identify the optimal zone of retrofit. An illustrative case study using real building data demonstrates how the framework might be applied to a real project and customized to achieve unique stakeholder priorities.


2017 ◽  
Vol 5 (1) ◽  
pp. 13 ◽  
Author(s):  
Gjergji Simaku

The expertise on building stock typology used openly available data from the Albanian statistical office. As the CENSUS was not especially designed for gathering data for the energetic evaluation of the building stock, some data were not available on the required level of detail. Estimations were necessary to extrapolate data to the existing stock. Technically, the study selected and described twenty representative categories of residential buildings typology for Albania. Were identified the level and the structure of final energy consumption at present and in the future by building age category, building type, climate zone, and energy end-use. Using an original template excel data sheet, were conducted the calculations of their thermal energy performance in three climate zones, designed standardized retrofit packages, calculated possible energy savings, and investment required by building type. The engineering principle of the Regulation in force, regarding to the legislative act of Energy Building Code in Albania, is beyond any doubt correct and carefully studied. The act is a rule book or the Regulation (energy building code - here The Code) which contains information that is sufficient to perform calculations of the different insulating layers for new construction after the year 2003. Also, the Regulation’s algorithms are still relevant in terms of calculation to provide Energy for heating demands in Albania. After 12 years, the Code remains the same and could provide either an optimal potential energy savings to the existing buildings, or an optimal cost-effective of building’s insulation without imposing a burden of high financial housing builders to multifamily prospective buyers. Based today Europe’s developments on Energy Performance of Buildings, the study is found relevant to provide a methodology for calculation of the energy performance in buildings (kWh/ m2a) based on volumetric coefficient heat losses (Gvt) for heating only, the existing indicator of the existing Code. The following study deals with the possibility of transposing the methodology used to the Code into an energy Performance based on minimum requirement for a new Regulation and/or EP Calculation Methodology based on efficient use of energy for heating and cooling purposes.


Author(s):  
Ilaria Ballarini ◽  
Vincenzo Corrado ◽  
Matteo Piro

The existing building stock presents a high potential of energy savings and CO2 emissions reductions. To this purpose, literature provides novel city-scale building-oriented studies, aimed at developing suitable tools for stakeholders, city planners, and decision-makers. To achieve an effective urban energy planning, urban energy systems (UES) models are developed; they employ a multi-domain approach, embracing the complex interactions in urban areas, such as energy flows, environmental indicators, social and economic factors. To perform an advanced modelling and to simulate the complexity of the UES, ICT (information and communications technology) represents nowadays the right answer to the needs of integration of data, tools, and actors in different domains. The chapter investigates the current studies in the field of building stock energy modeling and the application of advanced technologies to develop UES models. As an exemplification, the technological approach followed in the SEMANCO project to support urban scale energy modelling is presented.


2021 ◽  
Vol 11 (9) ◽  
pp. 4141
Author(s):  
Yovko Ivanov Antonov ◽  
Per Kvols Heiselberg ◽  
Michal Zbigniew Pomianowski

Reaching environmental targets set by the European Union (EU) requires a constant renovation of the existing building stock to nearly Zero Energy Buildings (NZEB) in a cost-optimal manner. Studies show that the renovation rate of the existing building stock is more than two times less than what is necessary to reach the targets. Furthermore, the majority of performed renovations across the EU reach just a small amount of energy savings, whereas NZEB renovations are rarely achieved. This paper proposes a methodology for the evaluation of renovation measures, aiming to provide decision support related to the selection of what to renovate and to what extent. The proposed method is rooted in the well-established cost-optimal methodology, yet it suggests a pre-step to package evaluation. This is done by means of a simplified cost-effective parameter (CEP), linking cost, lifetime, and energy savings. The methodology is demonstrated using a case study building in Denmark. The results show that the CEP provides good grounds for the compilation of single actions to packages. Further developments could focus on the sensitivity of the model inputs and integration of additional evaluation parameters to cost, such as environmental, architectural, comfort, risk, etc.


2021 ◽  
Author(s):  
J. J. McArthur ◽  
Chris Jofeh ◽  
Ann-Marie Aguilar

There is increasing literature demonstrating the link between building indoor environmental quality, and occupant health and productivity, driving the corporate real estate industry to investigate how to integrate wellness features in both new and existing building stock. Meanwhile, new voluntary standards to promote occupant health are becoming adopted alongside sustainability standards. As commercial building owners and tenants seek to improve occupant conditions and incorporate wellness, apparently conflicting priorities must be balanced, particularly improving indoor environmental conditions has the potential to increase energy. This paper presents a framework to consider retrofits holistically and considering the benefit of improved conditions both qualitatively and quantitatively. Where poor conditions exist, published literature demonstrates a lost productivity cost that exceeds typical building energy costs, and this is quantified in the financial analysis presented. Energy retrofits provide a unique opportunity to integrate wellness-enabling features because the energy savings can offset marginal energy or operating cost increases for particular wellness interventions. This paper presents a flexible, customizable framework to develop potential retrofit bundles and evaluate them considering economic, sustainability, wellness, risk and occupant experience factors to identify the optimal zone of retrofit. An illustrative case study using real building data demonstrates how the framework might be applied to a real project and customized to achieve unique stakeholder priorities.


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