What’s New in California’s Lighting Requirements for Commercial Buildings?
According to the U.S. Energy Information Administration, lighting uses 17% of electricity consumed by today’s typical commercial building. As the cost and efficacy of LED lighting systems improve compared to linear fluorescent lighting systems, the comparative energy savings for new buildings and existing buildings undergoing lighting retrofits continue to increase. These savings come from using an efficacious light source paired with lighting controls, such as occupancy, daylighting, institutional tuning, automated demand response, and personal controls.
The lighting requirements of California’s Building Energy Efficiency Standards (Title 24, Part 6 or Energy Code) aim to reduce lighting energy use and demand statewide. The 2019 iteration of the Energy Code took effect on Jan. 1, 2020. Those familiar with the 2016 Energy Code will find many changes to the requirements in the 2019 Energy Code. Notably, the Energy Code now includes requirements for health care facilities (Occupancy Group I-2), although there are many exceptions.
The following sections highlight key changes to the indoor and outdoor lighting requirements and assume some familiarity with terminology typically used by energy code publications. For detailed information, the California Lighting Technology Center (CLTC) at University of California, Davis (UC Davis) recently published a guide that includes all the nonresidential lighting requirements and terminology definitions.
Indoor lighting
Changes to indoor lighting requirements affect four key areas of the Energy Code:
- Lighting power allowances
- Power adjustment factors
- Lighting controls
- Additions, alterations, and repairs
Indoor lighting power allowances
On average, indoor lighting power allowances have reduced by 37% for the complete building method and 29% for the area category method as compared to the 2016 Energy Code. These reductions assume that all new construction, alterations, and additions will be installing LED lighting technologies starting Jan. 1, 2020. For the complete building method, the most significant decreases affect the following building types: religious facilities, assembly buildings, motion picture theaters, and grocery stores.
For the area category method, the most significant decreases occur in the following function areas: museum displays, dining areas in cafeterias and fast food restaurants, videoconferencing studios, beauty salons, and auditoriums. Additionally, many space types have been renamed, footnotes have been added, and general changes have been included to the area category requirements.
Power adjustment factors
Power adjustment factors (PAFs) provide flexibility when developing a lighting design, effectively allowing projects to reduce their reported lighting power use. PAFs incentivize the additional use of specific lighting controls and daylighting strategies. Three new PAFs have been added to encourage the use of clerestory fenestration, horizontal slats, and light shelves. Four PAFs from the 2016 Energy Code also remain available.
Projects may gain a 5% lighting power adjustment credit for implementing clerestory fenestration or horizontal slats and a 10% lighting power adjustment credit for implementing light shelves. Luminaires that are in a daylit zone adjacent to these devices are eligible for the credit. Additionally, these credits may be combined with the PAF credit for “Daylight Dimming plus OFF Control.” The light shelf and clerestory fenestration credits may also be combined if used in the same space.
Indoor lighting controls
The lighting control requirements contain minor revisions throughout, which are designed to make requirements more consistent and easier to apply in practice. The most significant updates were made to automatic daylighting controls and demand responsive lighting controls. Additionally, a new section titled “Control Interactions” has been added.
Automatic daylighting controls
The mandatory automatic daylighting control language has been restructured and clarified, combining language for parking garages and indoor-only applications. Explicit direction is now included requiring separate controls for luminaires in each daylit zone type: skylit, primary sidelit, and secondary sidelit.
A new exception has been added for areas under skylights where existing adjacent structures or outdoor objects block direct sunlight for more than 1,500 daytime hours per year between the hours of 8 a.m. and 4 p.m. Daylighting controls are not required in these areas. Additionally, an exception has been added for areas adjacent to vertical glazing below an exterior overhang that meets specific sizing requirements (see the Figure below). For these areas, automatic daylighting controls for the primary and secondary sidelit daylit zones are not required. Luminaires in sidelit daylit zones in retail merchandise sales and wholesale showroom areas are also now exempt.
Demand responsive lighting controls
The 2019 update moves the demand responsive lighting controls to a new section in the subchapter for the manufacturing, construction, and installation of systems, equipment, and building components. Lighting demand responsive controls requirements are now listed in Section 110.12–Demand Management, which includes demand response requirements for other building systems, such as HVAC systems and electronic message boards.
Updates reference specific communication standards maintained by the OpenADR Alliance, which standardizes, automates, and simplifies demand response devices and distributed energy resources by establishing an open, highly secure, two-way information exchange standard.
Updates to the demand responsive lighting controls section now require demand responsive controls to either be a certified OpenADR 2.0a, OpenADR 2.0b Virtual End Node (VEN), or be certified by the manufacturer as being capable of responding to a demand response signal from a certified OpenADR 2.0b VEN. Additionally, the updates allow for the use of alternative communication protocols, so long as the system also uses one of the mandatory protocols: Wi-Fi, ZigBee, BACnet, Ethernet, or hard-wiring. This allowance is ideal for cloud-based systems that offer demand response capabilities.
Control interactions
A new Sec. 130.1(f), has been added that defines the required interactions of all mandatory indoor lighting controls (manual ON/OFF, multi-level lighting, shut-off controls, automatic daylighting controls and demand responsive controls). The section defines how each system is configured to ensure that all functions of the mandatory lighting controls are permitted by the system as a whole.
Occupancy sensing and multi-level requirements in restrooms
Occupancy sensing and multi-level requirements in restrooms were updated in the 2019 Energy Code. Now, restrooms of any size are required to be equipped with occupancy sensing controls that automatically shut-OFF all lights when the space is unoccupied. This can be achieved using an occupancy sensor, partial-ON occupancy sensor, or vacancy sensor. Additionally, restrooms are now exempt from all multi-level controls requirements.
Lighting controls for health-care facilities
It is important to note that health-care facilities are exempt from multi-level lighting controls, shut-OFF controls, and demand responsive controls.
Indoor additions, alterations, and repairs
Indoor alteration requirements are now simpler and easier to apply in practice. Compliance thresholds and exemptions are now consistent across all compliance options. Now, alterations to indoor lighting systems that include 10% or more of the luminaires serving an enclosed space must meet one of three requirement options (see the Table below).
Option 1: Comply with the indoor lighting power and lighting control requirements for new construction (second column from right in the Table).
Option 2: Alterations using 80% or less of the indoor lighting power allowances for new construction must adhere to the lighting control requirements in the right column of the Table.
Option 3: Projects in small buildings or tenant spaces (5,000 sq ft or less) that include one-for-one luminaire alterations to more than 50 luminaires can retrofit with new luminaires or component modifications that achieve at least 40% power reductions over pre-alteration luminaires. The project must include the lighting controls shown in the right column of the Table.
If the project includes less than 10% of the luminaires in the enclosed space, or the enclosed space has just one luminaire, then the project is exempt from these requirements.
Outdoor lighting
Three key changes were made to outdoor lighting in the 2019 Energy Code:
- Lighting power allowances
- Luminaire cutoff requirements
- Lighting controls
The following sections highlight the outdoor lighting changes.
Outdoor lighting power allowances
Outdoor lighting power allowances vary based on sites with concrete or asphalt surfaces. Clarifications have been added to make the lighting allowances for lighting systems serving outdoor areas with concrete hardscape in Lighting Zones 2 and 3 more transparent.
Overall, the outdoor lighting power allowances have reduced from 2016 levels. Additional lighting power allowances are available for specific applications.
Luminaire cutoff requirements
The 2019 Energy Code luminaire cutoff requirements only apply to luminaires with a light output of 6,200 lm or greater. This is a change from the 2016 Energy Code, which required all lamps greater than 150W to comply with the luminaire cutoff requirements. Detailed requirements regarding backlight, uplight, and glare are contained in CALGreen (Title 24, Part 11).
Additionally, an exception has been added for outdoor lighting attached to high-rise residential or hotel/motel buildings that is controlled from the inside of a dwelling unit or guest room, such as porch lights.
Outdoor lighting controls
The 2019 Energy Code clarifies the functionality for many types of outdoor lighting controls. Specifically, language has been refined for automatic scheduling controls and motion sensing controls.
Automatic scheduling controls
New language refines the automatic scheduling controls functionality requirements and acceptance testing procedure to verify installed systems. Now, automatic scheduling controls need to be capable of reducing the outdoor lighting power by at least 50% but no more than 90%. Additionally, the device needs to be able to turn the lights OFF during periods of scheduled unoccupied periods and allow for the scheduling of at least two nighttime periods.
Motion sensing controls
Language has been added to clarify the functionality of motion sensing controls. Similar to automatic scheduling controls, the motion sensor control must be capable of reducing the lighting power by at least 50% but no more than 90% and be separately capable of turning OFF the lights during periods of vacancy.
New language has established a maximum timeout of 15 min. when there is no motion in the area, after which the system returns to its dimmed or OFF mode.
While it is still required for outdoor luminaires mounted at 24 ft above grade or lower to be paired with motion sensors, the exceptions have been updated. Now, all luminaires 40W or less are exempt from the motion sensing control requirement, regardless of their form factor or product category. Also, occupancy sensor requirements for incandescent luminaires rated over 100W have been removed.
Hathaway is senior development engineer and communications director at the California Lighting Technology Center at University of California, Davis. She can be reached at [email protected].
