The 2022 version of California’s energy code took effect on Jan. 1, 2023, superseding the 2019 version. Electrical construction professionals must adhere to its requirements for all new construction and alteration projects covered by the code and go out for permit.
Energy codes regulate buildings’ designed energy-efficiency. While a majority of states adopt model codes and standards, California developed its own: Title 24, Part 6 of the Building Standards Code. It is enforced by local building departments through the permit application process.
For lighting in nonresidential buildings, among many changes, the 2022 version notably reduces power densities and updates outdoor zones, while making two changes regarding mandatory requirements for lighting controls worthy of focus in this article. These include requiring occupancy-sensing in larger offices and changes to requirements for demand-responsive controls.
Title 24 already requires manual area, multilevel, automatic shutoff, automatic daylighting and demand-responsive controls. Prior to the 2022 version, occupant-sensing controls were required in a range of spaces such as offices 250 square feet and smaller. Demand-responsive lighting controls were required for buildings 10,000 square feet and larger.
Occupancy sensors. The 2022 version of Title 24 now requires occupancy sensors in all office areas regardless of size and limits the control zone for each sensor to 600 square feet. This enables deeper energy savings compared to time-based control and brings Title 24 in alignment with the latest versions of the International Energy Conservation Code (IECC). Note that undershelf and furniture-mounted task lighting controlled by a local switch and either a time switch or occupancy sensor are exempted.
How does it work? When the sensor detects occupancy, it may automatically turn the zone’s lighting on to any level up to full power. When the sensor detects a lack of occupancy, the lighting power in the zone must reduce by at least 80% of full power within 20 minutes. When all zones in the overall office area are unoccupied, the system must turn lights in all zones off within 20 minutes.
The light reduction of at least 80% in unoccupied zones means if one is occupied but others aren’t, there is at least some illumination in the office for user comfort. The light reduction must be the same in all unoccupied zones for a uniform appearance.
This requirement can be satisfied with existing technology. Most occupancy sensors control lighting digitally through a room controller or networked control system. Sensors can be configured for control zoning and interaction with other zones through software and, in some cases, hardware. Some tuning may be required to ensure zoning is aligned with workstations. Another option is luminaire-level lighting controls, where luminaires feature embedded sensors for individual zoning and can be networked for larger ones.
Demand-responsive lighting controls. Demand response is a strategy where building electrical loads are automatically reduced in response to a control signal that may originate at the electric utility. The 2022 version of Title 24 changed what projects are covered by this requirement to general lighting loads 4,000W and larger, with some exemptions.
How does it work? The lighting controls must be able to respond to a control signal by reducing installed full lighting power by at least 15%, to be confirmed through testing. The signal must be bidirectional but may use a wired or wireless pathway. If there is a disruption to communications, the demand-responsive controls must be able to continue all other specified control functions.
An OpenADR 2.0a or 2.0b Virtual End Note (VEN) must be included that is certified by the manufacturer to automatically implement the required control function. Alternately, the lighting control manufacturer must certify that their system is capable of responding to a demand response signal from another system’s OpenADR 2.0b VEN.
Additionally, plug loads are now included. If the building is required to have demand-responsive lighting control and automatic receptacle control, the automatically controlled receptacles must be capable of being turned off in response to a demand response signal. The owner can then choose which, if any, receptacles to include in the demand response strategy.
Note all of the above represent requirements to ensure the capability of enacting demand response, not a requirement for the building owner to execute it.
Learn Title 24. While this column describes two notable changes to Title 24’s lighting section, electrical professionals should be familiar with the full text, including any applicable exemptions. In addition to lighting, other big changes include mandatory requirements for some buildings to include photovoltaics and battery storage. Also, multifamily buildings were given its own sections as an application, which significantly added to the code’s body.
For more information, consult the 2022 version of Title 24, part 6.
Header image source: Shutterstock / Assia
About The Author
DiLouie, L.C. is a journalist and educator specializing in the lighting industry. Learn more at ZINGinc.com and LightNOWblog.com.