Using real occupancy in retrofit decision-making: Reducing the performance gap in low utilisation higher education buildings

The retrofit analysis relies on intuition and faith in the simulations that lead the decision-making process. However, intuition is built upon belief systems which become increasingly unjustifiable as building operation deviates from design whether in utilisation, occupant behaviours or climate. Higher education facilities are known for persistently low but well-recorded occupant presence and density. The low utilisation makes them susceptible to counterintuitive behaviours however, their registration data provides a means of identifying where intuition fails. When operation has little correlation with design it is possible for performance issues to appear to be symptoms of design considerations rather than root cause. Using a discrete space modelled in both EnergyPlus and SBEM as virtual case study g and class registration data, this paper explores how lighting retrofit simulation alludes to heating load concerns resulting from poor envelope and HVAC performance rather than heating management. This is achieved through utilisation of a new approach to scheduling utilisation and BMS systems for higher education facilities in EnergyPlus. The paper concludes suggesting the utilisation modelling method could replace the current heating efficiency credits approach approved for Part L2. Results include discussion on cost-benefit, legislative compliance and implications for retrofit decision-making.