Integrating building management systems (BMS) and building information model (BIM) to improve HVAC efficiency: A case study in Darwin

Abstract

A significant increase in energy consumption by the building sector has led to a substantial rise in greenhouse gas emissions. This study addresses the importance of integrating a Building Management System (BMS) and BIM to utilise heating, ventilation, and air conditioning (HVAC) systems to enhance building energy efficiency. The utilisation of HVAC and BMS has been recognised for many years. However, they are often set as fixed-temperature systems without considering daily weather changes, wasting energy and causing human discomfort. There is an increased capability of using the BIM model to efficiently operate buildings via solid geometry, such as size and space. Hence, this study demonstrates the efficient energy use BMS outside and its associations with BIM for an optimised BMS utilising a case study incorporating a mixed-use office building in the central area of Darwin's CBD in Australia. Field tests of the room temperature set point reset strategy, condenser water delivery temperature optimisation strategy and chilled water delivery temperature optimisation strategy were conducted to determine their effectiveness. The energy audit showed that retrofitting the existing BMS and HVAC system increased the electrical energy efficiency by 29%, with the space temperature set point achieving an 8% increase during the wet season and 11% during the dry season. The condenser water delivery temperature optimisation field test decreased efficiency by 7% during the wet season and a 3% increase in efficiency during the dry season. The chilled water delivery temperature optimisation field test resulted in a 5% increase in efficiency during the wet season and a 7% increase in efficiency during the dry season, whilst the space temperature set point reset and chilled water delivery temperature optimisation strategies confirmed improvements in efficiency during both the wet and the dry seasons, the thermal comfort of the occupants was compromised during the wet season when both these strategies were implemented. These findings can inform BMS management in general, especially in tropical regions.