Occupancy monitoring approaches: learnings from literature and current research

With evolving work patterns—especially in the post-COVID era, and with the rise of hybrid and remote work—understanding occupancy is more crucial than ever for managing building energy demand. These shifts have made predicting and optimising energy use more complex, highlighting the growing importance of occupancy monitoring in building energy management. The emergence of hybrid working arrangements in office spaces and 'working from home' has brought forward a novel challenge: periods of variable occupancy patterns leading to increased energy waste due to lack of building flexibility and demand response. Recognising that occupancy is an important factor in the flexibility and energy demand of buildings, this review exercise explores various techniques employed for monitoring occupancy in both domestic and office buildings. It examines quantitative and qualitative methods in literature and delves into changes in occupancy patterns and controlling building environments. Current challenges in understanding and capturing occupancy include the impact of hybrid working and the shift in work activities to employees' homes. This review also discusses the shortcomings of current data collection methods in adequately capturing occupancy at different environments as well as informing potential areas for future investigations. These summaries are supplemented by experiences from two distinct ongoing projects: a) An observatory of 2000 households in the UK, and b) Occupant perception of retrofits following the pandemic in a higher education building in Oxford, UK.