Low carbon design is often discussed in terms of material selection and embodied carbon, but reducing operational energy is also an important part of lowering a building's lifetime emissions. For architects and designers, demand-driven controls provide a way to reduce unnecessary lighting and HVAC operation while maintaining comfortable indoor conditions.

Booking.com's City Campus in Amsterdam demonstrates how this can be applied at scale. The 65,000m² headquarters has achieved BREEAM Excellent certification, a building sustainability rating similar to the NZGBC Green Star, and incorporates 832 rooftop solar panels and underground thermal energy storage. Integrated into the KNX building automation system are 1,272 ESYLUX ATMO multi-sensor presence detectors spread across open-plan offices, conference rooms and communal areas.

The ATMO T and ATMO O configurations used on the project combine occupancy and daylight detection with environmental sensing. Lighting is controlled in response to both presence and available daylight, allowing artificial lighting to be dimmed when sufficient natural light is available.

The same sensors also contribute to HVAC control. Temperature data is used to bring occupied spaces to a 21°C setpoint, which is automatically reduced when spaces are unoccupied. ATMO O sensors monitor VOC-based indoor air quality, increasing fresh-air supply when defined thresholds are exceeded and reducing ventilation again once conditions improve.

This approach maximises both energy efficiency and comfort by allowing building services to respond to actual use rather than operating continuously at fixed output or via an inflexible schedule.

In New Zealand, Simx supplies the full ESYLUX ATMO range. The ATMO T combines PIR and acoustic presence detection with light and temperature sensing; the ATMO A adds relative humidity measurement; and the ATMO O adds VOC-based air-quality measurement. All models provide 360° presence detection with an 8m diagonal detection diameter.

By providing a single KNX-based sensing platform, the ESYLUX ATMO range creates a practical design opportunity: reduce energy use not by compromising comfort, but by making building services operate more closely in line with actual demand.