scholarly journals A tool for Danish buildings energy retrofit design and evaluation using dynamic energy simulations

2020 ◽  
Vol 172 ◽  
pp. 18008
Author(s):  
Muhyiddine Jradi ◽  
Henrik Engelbrecht Foldager ◽  
Rasmus Camillus Jeppesen
Keyword(s):  
Assessment Tool ◽  
Dynamic Performance ◽  
Building Energy ◽  
Building Performance ◽  
Single Family ◽  
Design Development ◽  
Energy Retrofit ◽  
Energy Simulations ◽  
Family House ◽  
Retrofit Design

In general, static tools and simplified assessment approaches are still dominating the Danish building energy retrofit market. These static tools are generally associated with a large number of assumptions and tend to neglect the overall building dynamics. This leads to major uncertainties and substantial gaps between the predicted performance, promised before retrofitting, and the real building performance after carrying out the retrofit project. To overcome these challenges, this work presents the design, development and demonstration of DanRETRO, a tool for Danish buildings energy retrofit design and evaluation. The tool uses a large database of dynamic performance simulations employing EnergyPlus, for different building types, ages and sizes, allowing a preliminary assessment of the technical, economic and environmental impacts of various retrofit measures. In this regard, the tool provides a large selection of retrofit techniques and measures along with retrofit packages. DanRETRO is intended to be a comprehensive building energy retrofit assessment tool, but at the same time being simple to use with minimal inputs. The demonstration of the tool in an office building, a single-family house and an apartment in Denmark is presented and assessed. DanRETRO evaluation results are aimed to serve as a basis to aid energy retrofit projects decision-making.

A literature review of building energy simulation and computational fluid dynamics co-simulation strategies and its implications on the accuracy of energy predictions

2021 ◽  
pp. 014362442110204
Author(s):  
Manan Singh ◽  
Ryan Sharston
Keyword(s):  
Heat Transfer ◽  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Practical Implication ◽  
Convective Heat Transfer Coefficient ◽  
Building Energy ◽  
Coupled Analysis ◽  
Future Research ◽  
Building Performance ◽  
Energy Simulations

The paper presents a review of existing literature in the field of coupling Computational Fluid Dynamics (CFD) with Building Energy Simulations (BES) to better predict indoor environmental conditions and building energy implications. CFD is capable of providing a detailed analysis of airflow profile and temperature gradients in the space as well as better prediction of heat transfer involving convection and radiation. Whereas BES can provide dynamically changing boundary conditions to CFD to facilitate a precise transient analysis. Combining the two simulations provides a powerful framework to accurately predict building performance parameters. The review examines the variables exchanged between the two simulations and establishes that the Convective Heat Transfer Coefficient (CHTC) as the most important exchanged variable that can significantly improve the accuracy of energy simulations. Issues regarding the application of co-simulation mechanism are then discussed in terms of simulation discontinuities, along with strategies adopted by researchers to overcome the same. In the later sections, the review evaluates the applicability of co-simulation from the perspective of year-long building energy simulations and presents an overview of methods used in research to implement the same. Finally, the conclusions are discussed and the scope for future research in the field is presented. Practical implication: The review presents a critical analysis of essentially all major coupling strategies that can be used to perform a BES-CFD coupled analysis along with their strengths, limitations and possible application scenarios. Additionally, the problems associated with establishing the co-simulation are examined and various adopted solutions are presented along with methods implemented towards extending the practical applicability of such an analysis to encapsulate year-long simulations.

Single-Family Residential Building Energy Retrofit

2018 ◽  
pp. 248-274 ◽  
Author(s):  
Michał Pierzchalski
Keyword(s):  
Residential Building ◽  
Building Energy ◽  
Environmental Benefits ◽  
Single Family ◽  
Biomass Boiler ◽  
Main Assumption ◽  
Energy Retrofit ◽  
The 1960S ◽  
Technical Solutions

This chapter is a case study for the energy retrofit of an existing single-family residential building. The main assumption of the project was creating a model example for an energy retrofit with the aim of achieving the nZEB standard in existing residential building. The discussed building was built between the 1960s and the 1970s. The building was built using mixed technologies. The flooring on the ground floor was replaced; the foundation, external walls, and roof were thermally insulated. The windows and doors were replaced with higher parameter ones. Moreover, a modern biomass boiler was installed in the building along with the installation of a mechanical bidirectional ventilation unit with a heat recovery. Before the renovation, the building used about 133.4 GJ final energy for heating annually. After the renovation, the building uses about 8.89 GJ annually. The author describes all the stages of the renovation, the technical solutions, the calculations of economic and environmental benefits of the conducted renovations.

scholarly journals Proposed Method for Probabilistic Energy Simulations for Multi-Family Dwellings

2020 ◽  
Vol 172 ◽  
pp. 25011
Author(s):  
Stephen Burke ◽  
Pär Carling ◽  
Henrik Davidsson ◽  
Kristin Davidsson ◽  
Tomas Ekström ◽  
...  
Keyword(s):  
Energy Use ◽  
Probabilistic Method ◽  
Hot Water ◽  
Zone Model ◽  
Building Performance ◽  
Single Family ◽  
Energy Calculations ◽  
Family Model ◽  
Family Building ◽  
Energy Simulations

As regulations regarding energy use and emissions of CO2 equivalents in buildings become more stringent, the need for more accurate tools and improved methods for predicting these parameters in building performance simulations increases. In the first part of this project, a probabilistic method was developed and applied to the transient energy calculations and evaluated using a single-family dwelling case study. The method was used to successfully predict the variation of the energy use in 26 houses built in the same residential area and with identical building characteristics and services. This project continues the development and testing of the probabilistic method for energy calculations by applying it to a multi-family building. The complexity of the building model increases as the multi-family model consists of 52 zones, compared to the single-zone model used for the single-family dwelling. The multi-family model also includes additional parameters that are evaluated, such as the domestic hot water circulation losses. This paper presents the probabilistic method applied to the building performance simulations used to predict the energy use for the multi-family building and discusses the differences between the previous and new method used in this study.

Energy retrofit of a single-family house: Life cycle net energy saving and environmental benefits

2013 ◽  
Vol 27 ◽  
pp. 283-293 ◽  
Author(s):  
Marco Beccali ◽  
Maurizio Cellura ◽  
Mario Fontana ◽  
Sonia Longo ◽  
Marina Mistretta
Keyword(s):  
Life Cycle ◽  
Energy Saving ◽  
Environmental Benefits ◽  
Net Energy ◽  
Single Family ◽  
Energy Retrofit ◽  
Family House

scholarly journals Generation of a Test Reference Year for Alūksne, Latvia

2015 ◽  
Vol 33 (1) ◽  
pp. 46-54 ◽  
Author(s):  
Mārtiņš Ruduks ◽  
Arturs Lešinskis
Keyword(s):  
Selection Process ◽  
Meteorological Data ◽  
Weather Conditions ◽  
Building Energy ◽  
Weather Data ◽  
Building Performance ◽  
Climate Data ◽  
Meteorological Observations ◽  
Energy Simulations

Abstract Precise and reliable meteorological data are necessary for building performance analysis. Since meteorological conditions vary significantly from year to year, there is a need to create a test reference year (TRY), to represent the long-term weather conditions over a year. In this paper two different TRY data models were generated and compared: TRY and TRY-2. Both models where created by analysing every 3-hour weather data for a 30-year period (1984–2013) in Alūksne, Latvia, provided by the Latvian Environment Geology and Meteorology Centre (LEGMC). TRY model was generated according to standard LVS EN ISO 15927-4, but to create second model - TRY-2, 30 year average data were applied. The generated TRY contains typical months from a number of different years. The data gathered from TRY and TRY-2 models where compared with the climate data from the Latvian Cabinet of Ministers regulation No. 379, Regulations Regarding Latvian Building Code LBN 003-01. Average monthly temperature values in LBN 003-01 were lower than the TRY and TRY-2 values. The results of this study may be used in building energy simulations and heating-cooling load calculations for selected region. TRY selection process should include the most recent meteorological observations and should be periodically renewed to reflect the long-term climate change.

scholarly journals Life Cycle Cost Analysis of a Single-Family House in Sweden

Buildings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 215
Author(s):  
Bojana Petrović ◽  
Xingxing Zhang ◽  
Ola Eriksson ◽  
Marita Wallhagen
Keyword(s):  
Life Cycle ◽  
Life Cycle Cost ◽  
Single Family ◽  
Labor Costs ◽  
Construction Costs ◽  
Economic Parameters ◽  
A Minor ◽  
Family House ◽  
Replacement Operation

The objective of this paper was to explore long-term costs for a single-family house in Sweden during its entire lifetime. In order to estimate the total costs, considering construction, replacement, operation, and end-of-life costs over the long term, the life cycle cost (LCC) method was applied. Different cost solutions were analysed including various economic parameters in a sensitivity analysis. Economic parameters used in the analysis include various nominal discount rates (7%, 5%, and 3%), an inflation rate of 2%, and energy escalation rates (2–6%). The study includes two lifespans (100 and 50 years). The discounting scheme was used in the calculations. Additionally, carbon-dioxide equivalent (CO2e) emissions were considered and systematically analysed with costs. Findings show that when the discount rate is decreased from 7% to 3%, the total costs are increased significantly, by 44% for a 100-year lifespan, while for a 50 years lifespan the total costs show a minor increase by 18%. The construction costs represent a major part of total LCC, with labor costs making up half of them. Considering costs and emissions together, a full correlation was not found, while a partial relationship was investigated. Results can be useful for decision-makers in the building sector.

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