Office Lighting Control: How to Properly Plan Presence Detectors, Daylight, and Lighting Scenes
Alessandro Nicotra
Light
In short
— Lighting accounts for around 10 percent of Switzerland's electricity consumption. Occupancy and daylight controls significantly reduce consumption.
— In practice, systems often save less than promised. Careful planning and commissioning make all the difference.
— People accept automated systems when they are able to intervene themselves.
Good lighting switches on when you need it, adapts to daylight, and changes the mood in the evening. Lighting control saves a lot of energy in the process. However, it only works if it is planned for the people working under it, and not against them.
The best lighting control is the one you don't notice until you need it.
How much energy does office lighting control save?
Depending on the strategy, around a quarter to more than a third. In 2023, lighting accounted for 10 percent of Switzerland's electricity consumption, driven primarily by the service sector (SFOE). An evaluation by the Lawrence Berkeley National Laboratory across numerous studies found average savings of 24 percent with occupancy sensing, 28 percent with daylight harvesting, and 38 percent with combined strategies.
The details matter. At the Bläsi school building, simply reducing the shut-off delay of the occupancy sensors from 15 to 5 minutes yielded around 20 percent in savings (Minergie).
What does SIA 387/4 require in offices?
A limit value for lighting electricity demand, and that depends on the control system. The SIA 387/4 standard applies to new builds and renovations of 1,000 m² of energy reference area or more, as well as to tenant fit-outs (EnFK, Implementation Guide EN-111). Planning in occupancy sensing and daylight control makes it easier to meet the requirements. Minergie requires on average around 30 percent less than the SIA limit value.
Lines of light at LSEG in Geneva
Why do many systems save less than promised?
Because technology alone is not enough. A study by the Lucerne University of Applied Sciences and Arts showed that, in most cases, occupancy sensors saved significantly less energy than manufacturers' specifications led one to expect. Misplaced sensors, excessively long run-on times, or suboptimal settings eat up the savings.
And people push back against light they cannot control. A study by Lund University found that highly automated systems without manual override are often disabled or even sabotaged. The "manual on, automatic off" principle works better. According to an overview from the University of Washington, one study showed that power consumption dropped significantly with this approach, while user satisfaction increased.
How do you design good lighting control?
Starting from the space, not the catalogue. First, we clarify how a space is used and the atmosphere it should create. Then we design the control system to match.
Daylight first. Workstations near windows need little artificial light during the day. Daylight-responsive controls dim the light there automatically.
Occupancy where it makes sense. In meeting rooms, focus booths, auxiliary rooms, and circulation areas, the light turns off automatically. At the workstation, control remains in the user's hands.
Scenes for the day. A room can have crisp task lighting during the day and turn warm for guests in the evening. With a few clearly named scenes, this succeeds without an instruction manual. At the London Stock Exchange Group in Geneva, the sensors are integrated invisibly into the light lines, and if the use of the space changes, the lighting adapts without the need for renovations.
An open standard. With DALI, a standardized protocol according to IEC 62386, every luminaire can be addressed individually (DALI Alliance). This makes future adjustments straightforward.
Recalculating and fine-tuning. We verify every lighting design in Relux. After move-in, it pays off to check sensors and timing settings, as that is where a large portion of the savings lies.
What are the benefits of biodynamic lighting?
Potentially quite a few, but research is still cautious. The International Commission on Illumination (CIE) notes that bright light during the day and low light in the evening are beneficial. An international consensus recommends an adequate dose of light at eye level during the day for healthy adults and significantly less in the evening (CIE TN 015). These recommendations are explicitly formulated as initial guidance. We therefore plan primarily with daylight, bright interior surfaces, and warm evening light, and use color-changing artificial lighting where it provides a clear benefit.
What does this bring to the company?
Lower electricity costs, fulfilled regulations, and less maintenance. With combined control strategies, average savings are 38 percent according to the Lawrence Berkeley National Laboratory. Careful fine-tuning after moving in often yields even more, as shown by the example with shortened switch-off times. And because the SIA 387/4 standard also applies to tenant fit-outs, good control is often the easiest way to meet the requirements.
An open standard such as DALI also reduces the costs of subsequent adaptations: if the use changes, it is reprogrammed instead of rebuilt.
pom+ Industriehof, Zurich
Frequently Asked Questions
Is lighting control also worthwhile with LEDs?
Yes. While LEDs already save a lot of energy, effective control further reduces consumption and extends the service life of the luminaires.
Where should presence detectors be used?
Primarily in rooms that are temporarily unoccupied: meeting rooms, focus pods, secondary rooms, corridors. For workstations, "manual on, automatic off" has proven effective.
What is DALI?
A standardised lighting control protocol that allows each luminaire to be individually addressed and dimmed. It makes subsequent adjustments easier.
What is a lighting scene?
A saved setting for multiple luminaires suited to a specific situation, such as working, presentations, or evening events. A single push of a button is all it takes.
Does SIA 387/4 also apply to tenant fit-outs?
Yes, for new builds and renovations with an energy reference area of 1,000 m² or more, it also applies to tenant fit-outs.
Sources
Analysis of Swiss Energy Consumption 2000–2023 by End-Use, SFOE, 2024
Lighting Controls in Commercial Buildings, Williams et al., LEUKOS, Lawrence Berkeley National Laboratory, 2012
Good Lighting in Minergie Buildings, Minergie Switzerland, 2019
Implementation Guide EN-111: Lighting SIA 387/4, EnFK, 2018
Presence Detector Test, Lucerne University of Applied Sciences and Arts, 2013
Lighting Control Systems for Energy Saving and User Acceptance, Niko Gentile, Lund University, 2015
Electric Lighting and Personal Control, University of Washington, 2021
CIE Position Statement on Non-Visual Effects of Light, CIE, 2019
CIE TN 015:2023, CIE, 2023
What is DALI?, DALI Alliance
Good lighting is intuitive without pushing itself into the foreground.
Contact
Listening is our first draft.
Every project begins with a conversation. Tell us what you have in mind: a new working environment, a restaurant, a space for the future. We bring an open mind, curiosity, and experience in strategy, interior design, and lighting. We'd love to meet at our studio on Gutstrasse in Zurich. Or wherever your project is coming to life.