scholarly journals The Discrepancy between As-Built and As-Designed in Energy Efficient Buildings: A Rapid Review

2020 ◽  
Vol 12 (16) ◽  
pp. 6372
Author(s):  
Christine Eon ◽  
Jessica K. Breadsell ◽  
Joshua Byrne ◽  
Gregory M. Morrison
Keyword(s):  
Life Cycle ◽  
Energy Efficient ◽  
Building Energy ◽  
Energy Performance ◽  
Rapid Review ◽  
Building Performance ◽  
Performance Gap ◽  
Energy Efficient Buildings ◽  
Building Life Cycle ◽  
Building Standards

Energy efficient buildings are viewed as one of the solutions to reduce carbon emissions from the built environment. However, studies worldwide indicate that there is a significant gap between building energy targets (as-designed) and the actual measured building energy consumption (as-built). Several underlying causes for the energy performance gap have been identified at all stages of the building life cycle. Focus is generally on the post-occupancy stage of the building life cycle. However, issues relating to the construction and commissioning stages of the building are a major concern, though not usually researched. There is uncertainty on how to address the as-designed versus as-built gap. The objective of this review article is to identify causes for the energy performance gap in buildings in relation to the post-design and pre-occupancy stages and review proposed solutions. The methodology applied in this research is the rapid review, which is a variant of the systematic literature review method. Findings suggest that causes for discrepancies between as-designed and as-built energy performance during the construction and commissioning stages relate to a lack of knowledge and skills, lack of communication between stakeholders and a lack of accountability for building performance post-occupancy. Recommendations to close this gap during this period include better training, improved communication standards, collaboration, energy evaluations based on post-occupancy performance, transparency of building performance, improved testing and verification and reviewed building standards.

scholarly journals Understanding the Reasons behind the Energy Performance Gap of an Energy-Efficient Building, through a Probabilistic Approach and On-Site Measurements

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6178
Author(s):  
Pierryves Padey ◽  
Kyriaki Goulouti ◽  
Guy Wagner ◽  
Blaise Périsset ◽  
Sébastien Lasvaux
Keyword(s):  
Energy Efficient ◽  
Probabilistic Approach ◽  
Energy Performance ◽  
High Energy ◽  
Performance Gap ◽  
Post Evaluation ◽  
Energy Efficient Buildings ◽  
Ex Post ◽  
The Difference ◽  
Energy Efficient Building

The performance gap, defined as the difference between the measured and the calculated performance of energy-efficient buildings, has long been identified as a major issue in the building domain. The present study aims to better understand the performance gap in high-energy performance buildings in Switzerland, in an ex-post evaluation. For an energy-efficient building, the measured heating demand, collected through a four-year measurement campaign was compared to the calculated one and the results showed that the latter underestimates the real heating demand by a factor of two. As a way to reduce the performance gap, a probabilistic framework was proposed so that the different uncertainties of the model could be considered. By comparing the mean of the probabilistic heating demand to the measured one, it was shown that the performance gap was between 20–30% for the examined period. Through a sensitivity analysis, the active air flow and the shading factor were identified as the most influential parameters on the uncertainty of the heating demand, meaning that their wrong adjustment, in reality, or in the simulations, would increase the performance gap.

scholarly journals The Performance Gap in Energy-Efficient Office Buildings: How the Occupants Can Help?

Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1480 ◽  
Author(s):  
Qadeer Ali ◽  
Muhammad Jamaluddin Thaheem ◽  
Fahim Ullah ◽  
Samad M. E. Sepasgozar
Keyword(s):  
Energy Efficient ◽  
Behavioral Interventions ◽  
Energy Use ◽  
Energy Savings ◽  
Energy Performance ◽  
Office Buildings ◽  
Occupant Behavior ◽  
Energy Usage ◽  
Performance Gap ◽  
Energy Efficient Buildings

Rising demand and limited production of electricity are instrumental in spreading the awareness of cautious energy use, leading to the global demand for energy-efficient buildings. This compels the construction industry to smartly design and effectively construct these buildings to ensure energy performance as per design expectations. However, the research tells a different tale: energy-efficient buildings have performance issues. Among several reasons behind the energy performance gap, occupant behavior is critical. The occupant behavior is dynamic and changes over time under formal and informal influences, but the traditional energy simulation programs assume it as static throughout the occupancy. Effective behavioral interventions can lead to optimized energy use. To find out the energy-saving potential based on simulated modified behavior, this study gathers primary building and occupant data from three energy-efficient office buildings in major cities of Pakistan and categorizes the occupants into high, medium, and low energy consumers. Additionally, agent-based modeling simulates the change in occupant behavior under the direct and indirect interventions over a three-year period. Finally, energy savings are quantified to highlight a 25.4% potential over the simulation period. This is a unique attempt at quantifying the potential impact on energy usage due to behavior modification which will help facility managers to plan and execute necessary interventions and software experts to develop effective tools to model the dynamic usage behavior. This will also help policymakers in devising subtle but effective behavior training strategies to reduce energy usage. Such behavioral retrofitting comes at a much lower cost than the physical or technological retrofit options to achieve the same purpose and this study establishes the foundation for it.

Evaluation of Cooling, Heating, and Power (CHP) Systems Based on Building Energy-Rating

2007 ◽  
Author(s):  
N. Fumo ◽  
P. J. Mago ◽  
L. M. Chamra
Keyword(s):  
Energy Efficiency ◽  
Economic Analysis ◽  
Energy Efficient ◽  
Energy Use ◽  
Management Practices ◽  
Building Energy ◽  
Energy Performance ◽  
Energy Star ◽  
Star Rating ◽  
Energy Efficient Buildings

Cooling, Heating and Power (CHP) systems are a form of distributed generation that uses internal combustion prime-power engines to generate electricity while recovering heat for other uses. CHP is a promising technology for increasing energy efficiency through the use of distributed electric and thermal energy recovery-delivery systems at or near end-user sites. Although this technology seems to be economically feasible, the evaluation and comparison of CHP systems cannot be restricted to economical considerations only. Standard economic analysis, such as life cycle economic analysis, does not take in consideration all the benefits that can be obtained from this technology. For this reason, several aspects to perform a non-conventional evaluation of CHP systems have to be considered. Among the aspects to be included in a non-conventional evaluation are: power reliability, power quality, environmental quality, energy-efficient buildings, fuel source flexibility, brand and marketing benefits, protection from electric rate hikes, and benefits from promoting energy management practices. Some benefits of these non-economical evaluations can be transferred into an economic evaluation but others give intangible potential to the technology. This paper focus on a non-conventional evaluation based on energy-efficient buildings, which is associated to energy conservation and improvement of the building energy performance rating for government energy programs like Energy Star and Leadership in Energy and Environmental Design (LEED). Results show that the use of CHP systems could improve the Energy Star Rating in more than 50 points. The Energy Star Rating is significant on the LEED Rating as a building can score up to 10 points of the 23 available in the Energy & Atmosphere category on energy efficiency alone. As much as 8 points can be obtained in this category due to the Energy Star rating increment from the use of CHP systems. Clearly the use of CHP systems will help building owners to reach the benefits from these energy programs while improving the overall energy use and energy cost.

Solar radiation control passive strategy for reduction of heating and cooling energy use in arid climate: Case of Afghanistan

2021 ◽  
pp. 1420326X2110501
Author(s):  
Shambalid Ahady ◽  
Nirendra Dev ◽  
Anubha Mandal
Keyword(s):  
Developing Countries ◽  
Energy Efficient ◽  
Energy Use ◽  
Residential Building ◽  
Building Energy ◽  
Developed Countries ◽  
Energy Performance ◽  
Climatic Conditions ◽  
Local Conditions ◽  
Energy Efficient Buildings

Buildings are significant consumers of energy and producer of greenhouse gases worldwide, and serious efforts have been put into designing energy-efficient buildings. Significant technological advances have been achieved in developed countries; however, advances have rarely been adopted in developing countries like Afghanistan. Such trends emerge from the lack of research in designing energy-efficient buildings to local conditions, practices and materials. This research focused on building energy modelling and simulation to evaluate the energy performance impact of different shading and orientation. The research design follows a case study over an actual seven-storey multi-apartment residential building in the city of Mazar-I-Sharif, Afghanistan, using primary field data and dynamic simulation. Findings demonstrated that neighbouring structures have a positive correlation with a cooling demand. Meanwhile, south is the optimal orientation to face the building's glazed façade, saving up to 7.4% of cooling and 9.7% of heating energy. Moreover, movable shading devices installed on the building's openings in the summer season reduce the building energy load up to 19%, with a total energy cost reduction of AFN. 188,448 ($2447.37 US) annually. The study underlines the vast research scope in customizing building designs to Afghanistan's climatic conditions and other developing countries, thus contributing to buildings’ sustainability.

scholarly journals Towards a framework to evaluate the ‘total’ performance of buildings

2018 ◽  
Vol 39 (5) ◽  
pp. 609-631 ◽  
Author(s):  
Jonathon Taylor ◽  
Yanchen Liu ◽  
Borong Lin ◽  
Esfand Burman ◽  
Sung-Min Hong ◽  
...  
Keyword(s):  
Environmental Quality ◽  
Meta Analysis ◽  
Building Energy ◽  
Energy Performance ◽  
Building Performance ◽  
Indoor Environmental Quality ◽  
Performance Gap ◽  
Total Performance ◽  
The Uk ◽  
Occupant Satisfaction

Internationally, buildings are a major contributor to carbon emissions. Despite significant advances in the technology and construction of energy-efficient buildings, in many cases a performance gap between designed and actual performance exists. While much research has investigated the drivers of the building energy performance gap – both static and transient– there has been considerably less research into the total performance gap, defined here as performance gaps in building energy use, occupant satisfaction and Indoor Environmental Quality parameters such as thermal comfort and air quality which may impact on occupant health and wellbeing. This paper presents a meta-analysis of building performance data from buildings in the UK and China – selected due to their contrasting development environments – which illustrate the presence of and complexities of evaluating total performance gaps in both countries. The data demonstrate the need for (1) high end-use, spatial granularity and temporal resolution data for both energy and Indoor Environmental Quality, and (2) developing methodologies that allow meaningful comparisons between buildings internationally to facilitate learning from successful building design, construction methodologies and policy environments internationally. Using performance data from a UK building, a potential forward path is illustrated with the objective of developing a framework to evaluate total building performance. Practical application: While much research has examined building energy performance gaps, Indoor Environmental Quality and occupant satisfaction gaps are rarely included despite their relationship to energy. We use a meta-analysis of energy, indoor environmental quality, and occupant satisfaction data from buildings in the UK and China to illustrating the presence of and complexities of evaluating total performance gaps for buildings in the two countries, and the need for high resolution dynamic buildings data and novel methodologies for comparison between buildings across different contexts. Illustrative case studies are used to demonstrate potential future directions for evaluating ‘total’ building performance.

scholarly journals Calibration of a building energy model using operation conditions derived from monitoring

2019 ◽  
Vol 111 ◽  
pp. 03073
Author(s):  
Cristina Tanasa ◽  
Cristina Becchio ◽  
Stefano Paoloc Corgnati ◽  
Valeriu Stoian ◽  
Daniel Dan
Keyword(s):  
Energy Efficient ◽  
Model Simulation ◽  
Environmental Parameters ◽  
Building Energy ◽  
Energy Performance ◽  
Energy Model ◽  
Total Energy Consumption ◽  
Operation Conditions ◽  
Energy Efficient Buildings ◽  
Monthly Total

Building energy modelling and simulations play an important role in the design of energy efficient buildings but also in post-construction phases for commissioning, operation and optimization. With the use of data from monitoring systems related to the operation conditions of a building, calibrated simulations can be performed that accurately follow the real energy performance of a building. This paper present a procedure to achieve a calibrated building energy model simulation using monitoring data. The aim of the study is to verify/validate the results of the building energy model simulation against measured data. The study is based on an existing highly energy efficient building, which is continuously monitored in terms of energy consumptions and environmental parameters for several years now. The performance of the building energy model was assessed using statistical indices. The monthly total energy consumption comparison between simulated and measured shows that the building energy model managed to predict very closely the measured values. The accuracy of the building energy model in predicting air temperature was assessed as well.

scholarly journals Life Cycle GHG Emissions of Residential Buildings in Humid Subtropical and Tropical Climates: Systematic Review and Analysis

Buildings ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 6
Author(s):  
Daniel Satola ◽  
Martin Röck ◽  
Aoife Houlihan-Wiberg ◽  
Arild Gustavsen
Keyword(s):  
Systematic Review ◽  
Life Cycle ◽  
Residential Buildings ◽  
Construction Materials ◽  
Ghg Emissions ◽  
Energy Performance ◽  
Cycle Performance ◽  
Tropical Climates ◽  
Building Life Cycle ◽  
Total Life

Improving the environmental life cycle performance of buildings by focusing on the reduction of greenhouse gas (GHG) emissions along the building life cycle is considered a crucial step in achieving global climate targets. This paper provides a systematic review and analysis of 75 residential case studies in humid subtropical and tropical climates. The study investigates GHG emissions across the building life cycle, i.e., it analyses both embodied and operational GHG emissions. Furthermore, the influence of various parameters, such as building location, typology, construction materials and energy performance, as well as methodological aspects are investigated. Through comparative analysis, the study identifies promising design strategies for reducing life cycle-related GHG emissions of buildings operating in subtropical and tropical climate zones. The results show that life cycle GHG emissions in the analysed studies are mostly dominated by operational emissions and are the highest for energy-intensive multi-family buildings. Buildings following low or net-zero energy performance targets show potential reductions of 50–80% for total life cycle GHG emissions, compared to buildings with conventional energy performance. Implementation of on-site photovoltaic (PV) systems provides the highest reduction potential for both operational and total life cycle GHG emissions, with potential reductions of 92% to 100% and 48% to 66%, respectively. Strategies related to increased use of timber and other bio-based materials present the highest potential for reduction of embodied GHG emissions, with reductions of 9% to 73%.

Recommended angle of a modular dynamic façade in hot-arid climate: daylighting and energy simulation

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Seyedeh Samaneh Golzan ◽  
Mina Pouyanmehr ◽  
Hassan Sadeghi Naeini
Keyword(s):  
Energy Consumption ◽  
Energy Efficient ◽  
Energy Performance ◽  
Arid Climate ◽  
Visual Comfort ◽  
Building Envelopes ◽  
Content Type ◽  
Optimum Angle ◽  
Energy Efficient Buildings ◽  
Hot Arid Climate

PurposeThe modular dynamic façade (MDF) concept could be an approach in a comfort-centric design through proper integration with energy-efficient buildings. This study focuses on obtaining and/or calculating an efficient angle of the MDF, which would lead to the optimum performance in daylight availability and energy consumption in a single south-faced official space located in the hot-arid climate of Yazd, Iran.Design/methodology/approachThe methodology consists of three fundamental parts: (1) based on previous related studies, a diamond-based dynamic skin façade was applied to a south-faced office building in a hot-arid climate; (2) the daylighting and energy performance of the model were simulated annually; and (3) the data obtained from the simulation were compared to reach the optimum angle of the MDF.FindingsThe results showed that when the angle of the MDF openings was set at 30°, it could decrease energy consumption by 41.32% annually, while daylight simulation pointed that the space experienced the minimum possible glare at this angle. Therefore, the angle of 30° was established as the optimum angle, which could be the basis for future investment in responsive building envelopes.Originality/valueThis angular study simultaneously assesses the daylight availability, visual comfort and energy consumption on a MDF in a hot-arid climate.

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