Abstract
Overall heat transfer coefficient, also known as the intrinsic performance measurement of the building, determines the amount of heat lost by a building due to temperature difference between indoor and outdoor. QUB (Quick U-value of Buildings) is a short-term method for measuring the overall heat transfer coefficient of buildings. The test involves heating and cooling the house with a power step and measuring the indoor temperature response in a single night. Ideally, the outdoor temperature during QUB experiment should remain constant. To compare the influence of variable outdoor temperature, the QUB experiments are simulated on a well-calibrated model with real weather conditions. The experiments at varying outdoor temperature and constant outdoor temperature during the night show that the results in both conditions are nearly similar. A ±2 °C increase or decrease in the outdoor temperature during the QUB experiment can change the results in the measured overall heat transfer coefficient by ±5%. QUB experiments simulated during the months of winter show that the majority of results are ±15% of the steady-state overall heat transfer coefficient. The QUB results during the months of summer show relatively large variation. The large errors coincide with the small temperature difference between indoor and outdoor temperatures before the start of QUB experiment. The median error of multiple QUB experiments during summer can be reduced by increasing the setpoint temperature before the start of QUB experiment.
Highlights
Significant savings can be achieved in both new and existing buildings
Energy efficiency improvements require investments that are justified against the predicted savings
It is expected that outdoor conditions can deviate from the predicted weather conditions
Summary
Depending on the level and type of retrofit (deep or shallow) and the type of building, the potential savings can range from. 25% to 90% [1] Due to this potential, building energy efficiency sector received highest percentage (58%) of investments in energy efficiency sector in International Energy Agency (IEA) member countries (including six major emerging economies Brazil, China, India, Indonesia, Russian Federation, and Mexico) in 2017 [2]. Energy efficiency improvements require investments that are justified against the predicted savings. The saving predictions are based on simulation of baseline annual energy consumption and are hardly realized in field over the course of time due to several factors. This difference between estimated energy consumption and the measured energy consumption is usually referred to as ‘Performance
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
