I wrote this article to react to the previous post called “My office: a 100% intelligent building!” where Mr Steve Tettoc describes how great his new intelligent building is. His building, where everything is fully automatic and occupants have no control on their environment, seems really crazy to me.
And honestly I wonder if Mr Tettoc, and the visitors who commented that they thought it is a bright idea, have a real field experience of how things evolve in such buildings after a few years, and what their occupants really think about it.
It is widely agreed, and it is clear to me also, that buildings where the technical equipments (lighting, heating, windows openings, shades …) are only controlled by the occupants generate high level of energy consumption and wastes, especially in professional environment (office buildings …), because people may forget to switch off these equipments when they are not needed or when they leave, or just don’t make the effort as they don’t feel responsible for the associated costs.
Facing this situation, a trend of thought recommends the complete opposite solution: the occupant has no possibility to act, there is no switch or other manual adjustment controls, the building automation system is controlling 100% of building behaviour. This solution seems very interesting “on paper”, to optimize energy consumption, but in reality it has a number of weaknesses …
To be able to manage a building 100% automatically:
- automatic switching of equipment in the building or house can be felt as a nuisance by the occupantsAutomatic switching is well accepted when it is regular and predictable, but can be very bothering when it surprises the occupants: we all feel highly irritated when the blinds start to open automatically in the middle of an important conference (or at home during our Saturday afternoon rugby match), just because of a passing cloud.
- most importantly, an intelligent building or fully automatic, is stressful for the occupants.
- you need to be able to manage all requirements of comfort & efficiency, and choose the best compromise between these 2 contradictory strategies.
- you also have to take into account the possible failure modes of the building automation equipmentsNo product has infinite life duration: what will happen when the temperature sensor starts to loose its accuracy, when the motors opening the window or in charge of ventilation will jam, and there is no way to manually override the automatic system?
People generally like to have control over their. This not just casual observation, it has been proven using empirical data. When you don’t have any control over your environment, you easily feel like you are “trapped” and dependent on the proper functioning of machines. This feeling is reduced in buildings open to the public, but is fundamental in office buildings, houses and semi-collectives places like meeting rooms or classrooms.
This notion of “bad feeling” is not only related to physical comfort (temperature, lighting, acoustic, air quality …) but also to psychological comfort: to “feel good” depends also on other elements like aesthetics and ergonomics of the inside and outside of the building, of the acceptability of its functioning principles and in particular of its automatisms.
Why is it important that the occupants “feel good”? It is obviously a vital criterion for hotels or restaurants and directly impacting the business, but it is also essential in offices or schools as a “bad feeling” will mean a loss in efficiency and productivity of the occupants. And the costs of this inefficiency are much higher than the energy cost reduction.
One example: 2 people in a meeting room, one is opening the window because it is too warm (20°C), and the other stands up to close it because it is too noisy. The best balance between thermal & acoustic comfort is different from person to person, and depends on the activity in the meeting room: a net conference will give priority to acoustic need, a creativity session to the adequate room temperature. In a concert hall, no compromise would be given to absolute “silence”, whatever the temperature.
So this why, in my opinion, the intelligent building where everything is automatic, often presented as a great solution to reduce the consumption, is a utopia that does not or cannot take into account the need of the occupants to “feel good” to be efficient.
How can we find the best balance between energy savings, and occupant comfort and efficiency?