scholarly journals Usability of the EPC Tools for the Profitability Calculation of a Retrofitting in a Residential Building

2018 ◽  
Vol 10 (9) ◽  
pp. 3159 ◽  
Author(s):  
Alex Gonzalez Caceres ◽  
Muriel Diaz

After the oil crisis in the 70s energy regulation codes were implemented, but a great portion of existing dwellings have not been retrofitted to current requirements. To face this issue several actions were taken in the European Union (EU), among these, the implementation of Energy Performance Certificates (EPC), which include a Recommendation List of Measures (RLMs) to retrofit buildings. Some concerns exist about the lack of confidence on these recommendations. The main objective of this study is to analyze the usefulness of the EPC, answering if it is possible to deliver a realistic financial assessment about renovation strategies using these tools. The study is based on three indicators: Consumption, energy saving variations and profitability. The study is based on a renovation project case study, where simulations and Life Cycle Cost Assessment (LCCA) were performed, in order to identify the different results that EPC’s and an energy efficiency assessment could lead to. The results show important differences in all the concepts evaluated.

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4100
Author(s):  
Mariana Huskinson ◽  
Antonio Galiano-Garrigós ◽  
Ángel Benigno González-Avilés ◽  
M. Isabel Pérez-Millán

Improving the energy performance of existing buildings is one of the main strategies defined by the European Union to reduce global energy costs. Amongst the actions to be carried out in buildings to achieve this objective is working with passive measures adapted to each type of climate. To assist designers in the process of finding appropriate solutions for each building and location, different tools have been developed and since the implementation of building information modeling (BIM), it has been possible to perform an analysis of a building’s life cycle from an energy perspective and other types of analysis such as a comfort analysis. In the case of Spain, the first BIM environment tool has been implemented that deals with the global analysis of a building’s behavior and serves as an alternative to previous methods characterized by their lack of both flexibility and information offered to designers. This paper evaluates and compares the official Spanish energy performance evaluation tool (Cypetherm) released in 2018 using a case study involving the installation of sunlight control devices as part of a building refurbishment. It is intended to determine how databases and simplifications affect the designer’s decision-making. Additionally, the yielded energy results are complemented by a comfort analysis to explore the impact of these improvements from a users’ wellbeing viewpoint. At the end of the process the yielded results still confirm that the simulation remains far from reality and that simulation tools can indeed influence the decision-making process.


Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2817
Author(s):  
Valeria Annibaldi ◽  
Federica Cucchiella ◽  
Marianna Rotilio

In the European Union, about 40% of energy consumption and 36% of CO2 emissions come from buildings; therefore, the improvement of their energy performance is a strongly focused issue. In particular, the energy efficiency of the building envelope is a very important element to pay attention to. Many studies have been conducted on this field of research, and the study illustrated in this paper also belongs to this topic. In particular, this article presents a multidisciplinary method to find sustainable solutions for energy efficiency in Italian climatic contexts using the Life Cycle Cost Analysis approach. In detail, this paper defines the reference scenario and then deepens the methodology used to determine the economically optimal thickness of a specific insulating material—hemp fiber—applied to a specific type of wall—uninsulated cavity walls made of hollow bricks, which are very widespread in Italy. The analysis is developed in relation to three different regions—Piedmont, Abruzzo, and Campania. The results show that the economically optimal thickness is different for each region analyzed and demonstrates how energy efficiency strategies must be carefully weighed according to the specific conditions of the site.


Energies ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2469
Author(s):  
Evi Lambie ◽  
Dirk Saelens

Since households are one of the most energy-intensive sectors in Europe, retrofit of dwellings is promoted to increase energy efficiency. Recent research, however, shows that the energy performance after retrofit does not always meet the target values, which can be caused by amongst other things, a deviating building envelope performance. This paper compares the theoretical and measured building envelope performance for a real-life case study in post-retrofit state, in order to illustrate the limitations of calculation methods and characterization models. First, the performance is evaluated on building scale by verifying the correspondence between the default theoretical heat loss coefficient (HLC) and the measured HLC, which was determined by following the guidelines formulated within IEA EBC Annex 58 and Annex 71. In order to illustrate the limitations of the standard calculation method in real-life conditions, the theoretical variability of the HLC is evaluated, generated by variating infiltration heat losses and heat exchange with neighboring dwellings. Second, the performance is investigated on a component scale by assessing the theoretical and measured thermal resistances, identified from heat flux tests. Additionally, nonhomogeneous assembled components and air leaks are simulated to verify probable causes for the locally varying measured values and to illustrate the limitations of calculations and characterization methods. The results illustrate the limitations of the calculation methods by the assessment of the strong variability of the theoretical HLC, depending on assumptions regarding infiltration and heat exchange with neighboring dwellings. In addition, component simulations indicated that deficiencies on a component scale could be caused by a nonhomogeneous assembly and air cavity flows of the component. Moreover, a detailed assessment of an unreliable thermal resistance illustrates the limitations of the used characterization method. Finally, a contrast was found between the quite good performance on building scale (15% deviation between the theoretical and measured HLC) and poor performance on a component scale (only one out of nine monitored components met their theoretical target values), which illustrates the complexity of the building envelope performance.


2020 ◽  
Vol 197 ◽  
pp. 02002
Author(s):  
Ilaria Marotta ◽  
Francesco Guarino ◽  
Maurizio Cellura ◽  
Sonia Longo

Since the building sector is responsible for 40% of the world’s electricity demand, it is essential to act on it in order to reduce emissions of climate change gases on a global scale, as expressed also in the latest directive on the energy performance of buildings. A design approach that focuses on the energy flexibility of buildings can contribute to the improvement of its energy-environmental performances. In this context, the objective of the study is the analysis of the energy performance of a residential building in Sicily and the definition of strategies aimed at increasing its energy flexibility. In particular, the case study is a 631 m2 single-family house, modeled and simulated in TRNSYS environment. The approach involves the development of scenarios to reduce operating costs and CO2 emissions during the use phase of the building. Rule Based Control algorithms are implemented. The flexible control reacts to a price or emission signal, by modulating the heating set-point accordingly. The results highlighted significant increases in energy flexibility. The economic algorithm achieves savings of 21.46%, accompanied by a 15% reduction in emissions. The environmental algorithm allows to reduce CO2 emissions by about 30%. The economic impact is positive, with a 17.58% reduction in costs.


Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1032 ◽  
Author(s):  
Faidra Kotarela ◽  
Anastasios Kyritsis ◽  
Nick Papanikolaou

Cost-effective energy saving in the building sector is a high priority in Europe; The European Union has set ambitious targets for buildings’ energy performance in order to convert old energy-intensive ones into nearly zero energy buildings (nZEBs). This study focuses on the implementation of a collective self-consumption nZEB concept in Mediterranean climate conditions, considering a typical multi-family building (or apartment block) in the urban environment. The aggregated use of PVs, geothermal and energy storage systems allow the self-production and self-consumption of energy, in a way that the independence from fossil fuels and the reliability of the electricity grid are enhanced. The proposed nZEB implementation scheme will be analyzed from techno-economical perspective, presenting detailed calculations regarding the components dimensioning and costs-giving emphasis on life cycle cost analysis (LCCA) indexes—as well as the energy transactions between the building and the electricity grid. The main outcomes of this work are that the proposed nZEB implementation is a sustainable solution for the Mediterranean area, whereas the incorporation of electrical energy storage units—though beneficial for the reliability of the grid—calls for the implementation of positive policies regarding the reduction of their payback period.


2021 ◽  
Vol 16 (3) ◽  
pp. 87-108
Author(s):  
Nadeeka Jayaweera ◽  
Upendra Rajapaksha ◽  
Inoka Manthilake

ABSTRACT This study examines the daylight and energy performance of 27 external shading scenarios in a high-rise residential building in the urban tropics. The cooling energy, daytime lighting energy and the spatial daylight autonomy (sDA) of the building model were simulated in Rhino3D and Grasshopper simulation software. The best performance scenario (vertical and horizontal shading on the twentieth floor, horizontal shading only for the eleventh floor and no shading for the second floor) satisfied 75 sDA(300lx|50) with corresponding annual enery performance of 16%–20% in the cardinal directions. The baseline scenario, which is the current practice of providing balconies on all floors, reduced daylight to less than 75 sDA on the eleventh and second floor, even though it had higher annual enery performance (19%–24%) than the best performance scenario. Application of the design principles to a case study indicated that 58% of the spaces had over 75 sDA for both Baseline and Best performance scenarios, while an increase in enery performance of 1%–3% was found in the Best performance scenario compared to the Baseline.


Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 564
Author(s):  
Przemysław Markiewicz-Zahorski ◽  
Joanna Rucińska ◽  
Małgorzata Fedorczak-Cisak ◽  
Michał Zielina

Lowering energy consumption is one of the most important challenges of the modern world. Since the construction sector accounts for 40% of total energy consumption worldwide, the Parliament of the European Union has developed a Directive, according to which all newly designed and thermally upgraded buildings should meet the requirements of almost zero energy demand (nZEBs) from 1 January 2021. At the same time, in Poland, but also in many other countries in the world, there is a growing oversupply of office space in large cities with a simultaneous increase in demand for apartments, which is caused, among other things, by the increase in the share of remote work and the COVID-19 pandemic. Consequently, this is forcing owners to change the use of buildings from office to residential. This article analyses the possibilities of changing the function of an office building to a multi-family residential building. For both functional solutions, a comparative energy analysis was carried out, taking into account different work schedules and the requirements for new buildings with zero energy demand. The analyses have shown that changing the form of use of an office building to a multi-family building without significant financial and technical costs is possible. On the other hand, the reverse change of the form of use is much more difficult and, in many cases, practically impossible. Due to the fact that many offices are now multinational corporations, this issue is global.


Sign in / Sign up

Export Citation Format

Share Document