Codes and Standards Enhancement (CASE) Report
The Statewide CASE Team 2019 Title 24, Part 6 Final CASE Report is available below. The Final CASE Report incorporates feedback received during utility-sponsored stakeholder meetings, Energy Commission Pre-Rulemaking workshops, and personal communication with stakeholders. We encourage stakeholders to email feedback on the Final CASE Report to firstname.lastname@example.org. You can also participate in the 2019 Title 24, Part 6 Standards updated by attending the Energy Commission workshops and submitting written comments to the rulemaking docket. Refer to the Pre-Rulemaking and Rulemaking Workshop Notices for instructions on how to submit comments to the Energy Commission’s docket (available here).
This CASE Report recommends revisions to the existing requirements for nonresidential lighting alterations. The proposed code changes and the rationale for the changes are summarized below.
Clarify that lighting alteration projects that increase lighting power are subject to the lighting alteration code.
Lighting retrofit projects that increase lighting power result in higher energy use in buildings. These projects should demonstrate that retrofitted areas can meet LPA and should be subject to the lighting alteration code. Also, requiring projects that increase lighting power to comply with the lighting alteration code aligns Title 24, Part 6 with ASHRAE 90.1-2016: Energy Standard for Buildings Except Low-Rise Residential Buildings.
Reduce the number of luminaires from two to one per enclosed space in the existing exception to the lighting alteration code.
The current exception for enclosed spaces with one or two luminaires exempts private offices that often have two luminaires installed. Private offices should be subject to the lighting alteration code.
Require partial OFF occupant sensing controls for stairwells under Option 3 while continuing to exempt corridors from partial OFF occupant sensing controls under Option 3.
The installation of occupant sensing controls in stairwells during a retrofit project is generally feasible, unlike the installation of occupant sensing controls in corridors.
The luminaires in stairwells are often larger and can have occupancy sensors built into the luminaires. In addition, the wiring in stairwells is often exposed (providing easy access). However, the luminaires in corridors are often smaller and lack the space for occupancy sensors. The wiring in corridors is often concealed in hard ceilings or walls (leading to higher lighting retrofit cost).
Therefore, the lighting alteration code should not exempt stairwells from occupant sensing controls under Option 3, but should continue to exempt corridors.
Require a reduction of total existing lighting wattage of altered luminaires by 50 percent of the rated wattage under Option 3 rather than 50 percent for office, retail, and hotel and 35 percent for all other occupancies.
The parity in terms of delivered energy savings needs to be maintained among three compliance options. Lower 2019 LPD levels affect the parity of three compliance options, particularly for restaurants, schools, and small retail, as demonstrated by the results of the Lighting Alteration Model v2.0. In terms of delivered energy savings, Option 3 outperforms Option 1 and 2 for schools and small retail, when the reduction of existing wattage under Option 3 is set to 50 percent. The measure also improves the parity of Option 3 to Option 1 and 2 for restaurants.
Further, having two wattage reduction percentages under Option 3 led to inconsistent application of code requirements in the field. Reporting compliance under Option 3 on the space type by space type basis as intended in 2016 Standards is also burdensome. The code should specify a single wattage reduction percentage for Option 3 and should require reduction of total existing wattage of altered luminaires.
The Statewide CASE Team recognizes that if the measure to require 50 percent wattage reduction under Option 3 is adopted, compliance using Option 3 will not be feasible for some lighting retrofit projects. However, for those lighting retrofit projects, the other two compliance pathways will still be available.