Commercial Lighting Controls in Phoenix, AZ

The Valley averages around three hundred sunny days a year. That is an enormous amount of free light falling on perimeter zones, atriums, warehouses with skylights and parking structures — and in most Phoenix buildings, very little of it is being used to reduce electric lighting.

Daylight harvesting was often installed to satisfy the energy code and then never tuned. The photocell setpoints are at their factory defaults, the fade behaviour is abrupt enough that occupants notice and complain, and someone eventually put the zone into manual override. The equipment is there; the benefit is not.

The second Phoenix-specific factor is glare and heat. Aggressive daylight response without attention to blind position and solar angle produces spaces people find uncomfortable, which is how well-intentioned daylight zones end up permanently overridden. Commissioning against measured light levels in the actual space, at the times of day complaints occur, is what separates a daylight system that works from one that gets switched off.

In Phoenix the two systems are more connected than they look. Lighting is a cooling load — every watt of electric light in a conditioned space becomes heat the HVAC system has to remove, and in a cooling-dominated climate that penalty runs most of the year rather than seasonally.

Cutting unnecessary lighting runtime reduces both the lighting bill and the cooling load it creates. Where the lighting platform exposes a usable interface, integrating it with the BAS means occupancy and after-hours behaviour are decided once, and the disagreement between two vendors’ calendars stops being a recurring source of complaints.