Page 43 - Energize May 2022

TECHNICAL

Occupant behaviour these assumptions are vulnerable to being significantly different from the post-occupancy
As one source notes, “Buildings don’t reality.
use energy: people do.” Studies have It is generally agreed that to account for the impact of occupant behaviour on the
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shown that occupant behaviour is building EPG, more accurate and reliable occupant behaviour models are needed.
seen to be a significant contributor to
the EPG, therefore, an understanding Anthropocentric (human-centric) building design
of occupancy energy behaviour and It is commonly understood that the built environment has significant impact on people’s
its implications for energy use is vital. wellbeing. Consequently planning, design and operations of the built environment should
In many cases buildings are designed always take this into consideration. 4
without taking human behaviour unto Buildings for commerce and industry are designed to provide a work environment for
account sufficiently. 1 people, so the function of people in a building is focused on performing work, not on saving
Occupants have a substantial energy. While buildings must meet basic environmental and safety standards, building codes
influence on the energy performance of are primarily defined around the performance of the physical infrastructure rather than
a building by handling controls, such as capturing the performance of a person in a building. As a result, the building energy agenda
those for lighting, sun shading, windows, has recently focused on making these work environments as energy efficient as possible.
set points and office equipment, and Could this focus on energy efficiency be negatively affecting people’s wellbeing and thus
also through their presence, which affect people’s performance and ability to contribute to environmental, economic and social
may deviate from assumed schedules. sustainability?
People are very different in their Poor design can have such a critical impact on the creativity and innovation required
behaviour, through culture, upbringing for knowledge work that a radical shift in design focus may be deemed necessary. That
and education, making their influence on radical reconsideration may show that even small changes – not just to design – but to the
energy consumption highly variable. way information about both the building and the person are presented, may significantly
The primary reason that occupant improve performance.
behaviour causes the EPG is its The goals of current research are to put people at the centre of building performance
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uncertainty and unpredictability at the and to develop new measures and models which better capture the complexity of
design stage. Occupant behaviour is a these interactions. Plans are to measure the “dynamic” changes in and around the local
complicated mechanism, influenced by environment on people’s performance in that environment. These measures will indicate
multiple contextual factors including ways to create new models of building environments, which in turn will be available to
environmental conditions, psychological help inform policy for building quality that takes people’s wellbeing in these environments
reasons and sociological factors. Studies into account. These models will also help design new kinds of environmental interaction
which compare the predicted and actual tools.
energy performance of a high-density For instance, much current attention is focused on smart meters to encourage change in
office building, focusing on electricity behaviour around energy use. This is a very one-way view of interaction with buildings; it’s
consumption due to lighting, small all related to people reacting to the building, and not the building to the people who use it.
power and catering equipment, rather What if a building knew something about a person’s state and tasks and could react to their
than thermal loads, confirmed that requirements? 3
occupants’ operation of this equipment
is hard to predict at the design stage and References
that the accuracy of the model can be 1. T Hopson: “Advanced Energy Metering”, Schnackel Engineers, Inc. White Paper,
significantly improved by using post- September 2019.
occupancy evaluation data to reduce the 2. E Vard: “Why modern buildings must have energy metering and monitoring systems”, EEP,
EPG. February 2016.
Another type of behaviour which 3. X Shi, et al: “Magnitude, Causes, and Solutions of the Performance Gap of Buildings: A
contributes to the EPG is the occupants’ Review”, Sustainability, November 2019.
movement in building spaces. Energy 4. “Performance gap between building design and operation”, Designingbuildings.co.uk,
simulation requires that the number January 2022.
of people and their occupying hours 5. J Barlow: “Refresh: Remodeling Building Design Sustainability from a Human Centered
are specified in simulation models. Approach”, ESPRC EP/K02189306518.
However, it is difficult to accurately 6. Y Tao: “Modelling and Data Infrastructure for Human-Centric Design and Operation of
predict this information at the design Sustainable, Healthy Buildings through a Case Study”, Building and Environment: Volume
stage. A commonly used method is to 170, March 2020.
assume the number of people and their 7. K Janda: “Buildings don’t use energy: People do”, Architectural Science Review, February
occupying hours in building spaces based 2011.
on building types, space functions, and
other rules of thumb. Unfortunately, Send your comments to rogerl@nowmedia.co.za

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