Nonresidential Grid Integration

Measure Description

The focus of the nonresidential grid integration measure is to update the existing the requirements to better align with the current demand management and demand response (DR) marketplaces. This includes new time depended valuation of energy prices, demand responsive lighting equipment and labor prices, available communication protocols, additional thermal energy storage (TES) systems aside from chilled water storage, and commercial heat pump water heaters (HPWHs). Bringing the requirements in line with current practices would help ensure that newly constructed nonresidential buildings are positively contributing to grid stability, which is critical as California aims to achieve its renewable portfolio goals and building zero net energy goals. In this CASE Report, the Statewide CASE Team refer to demand management as the ongoing or day-to-day holistic practice of using building controls to operate equipment to optimize electric demand, measured in kilowatts (kW). DR is thus a component of demand management, referring to the additional adjustments to equipment a customer takes when notified by the utility.  

Demand Responsive Lighting Systems

The proposed measure would change the mandatory language in Section 110.12(c) demand responsive lighting controls by replacing the existing 10,000 square foot threshold with a threshold of 4,000 total design watts. Total design wattage, as defined in the Section 140.6(a) of Title 24, Part 6, would replace square footage as the threshold metric because it more effectively captures the direct saving potential of demand responsive lighting. The proposed code change would also revise the current 0.5 watts per square foot exemption so it references the 0.5 watt per square foot exemption of the multi-level lighting controls in Section 130.1(b).  

Compliance Option for HPWH Demand Management Systems 

The proposed code change would expand the HPWH demand flexibility compliance credit that is available for residential buildings that use the performance approach to comply with code so that a similar credit would also be available for nonresidential buildings. This change would help nonresidential buildings contribute positively to grid stability, which is critical as California aims to achieve its renewable portfolio and decarbonization goals. Specific revisions include updating Joint Appendix 13 – Qualification Requirements for Heat Pump Water Heating Demand Management Systems (JA13) so the language is more inclusive of HPWH systems installed in nonresidential buildings. The updated language in JA13 would align with the eligibility requirements for the Self-Generation Incentive Program  (SGIP), which added HPWH as an eligible measure in January 2020.14 For this compliance option to become available for use, the compliance software would need to be updated to add a feature that would simulate the energy impacts of operating HPWHs with demand management capabilities enabled, which could include optimizing for utility time-of-use or critical peak pricing rates. 

The proposed compliance credit would apply to all nonresidential building types for new construction, additions, and alterations. The value of the credit would vary by building type with the value credit calculated by the compliance software and taking hot water draw schedules, control strategies, and climate impacts into account. The credit would apply to both integrated (with tank) HPWH units (unitary systems) and central HPWH systems commonly configured as split systems, with separate storage tank and pump. 

Compliance Options for Thermal Energy Storage

To enable load shifting, the Statewide CASE Team proposes allowing compliance credit for thermal energy storage (TES) technologies beyond the existing chilled water systems by adding features to the compliance software for these additional systems. TES with phase change materials and ice storage enable a building to shift electricity use across hours of the day based on time-of-use or critical peak pricing rates and grid needs. The specific compliance options being considered include modifications to TES algorithms and compliance software to integrate the ThermalStorage:Ice:Detailed EnergyPlus object, which will allow designers to simulate the energy impacts and receive compliance credit for three additional types of TES systems that are already eligible to receive compliance credit but the software does not yet support: Ice-on-Coil Internal Melt, Ice-on-Coil External Melt, and Eutectic Salt.

Demand Responsive Control Simplification and Cleanup

This submeasure aims to simplify and streamline requirements for demand responsive controls. Section 110.12(a)2 would be amended to allow for any bi-directional communication methods to be used within the building site instead of limiting the allowable communication methods to only Wi-Fi, ZigBee, BACnet, Ethernet, or hard-wiring as 2019 Title 24, Part 6 requires. Sections 110.12(a)3 and 110.12(a)4 would be removed in an effort to simplify code language, removing superfluous language that can be clarified in the compliance manual instead of the code language itself.

Submeasures Moved to Future Code Cycles

The Statewide CASE Team is no longer pursuing the proposed changes listed below.

Outdoor Lighting Demand Management

The demand management control requirements for lighting systems only addresses indoor lighting. This measure review would explore the cost-effectiveness of including mandatory requirements for outdoor lighting demand management.

Alternative HVAC Control Strategies: Compressor Control

The focus of the nonresidential grid integration CASE initiative is to adjust the demand response control requirements so buildings that comply with Title 24, Part 6 are more likely to use their controls to implement load management on a day to day basis, as well as participate in reliability or economic demand response events. This will help newly constructed nonresidential buildings contribute to grid reliability in a positive way, which is critical as California aims to achieve its energy and climate goals.

Currently, demand responsive controls for HVAC must be capable of increasing or decreasing temperature setpoints by four degrees. This requirement would remain in place, so at a minimum DR controls would be required to enable temperature adjustments to non-critical zones and this temperature adjustment strategy is verified through acceptance testing.

Temperature setpoint adjustments are the most common load management strategy for nonresidential buildings, but other control strategies focusing on specific HVAC equipment exist that offer more direct and focused load management. The current code requires that building have the capability of automatically adjusting temperature setpoints when a Demand Response (DR) Signal is received and that a specific temperature adjustment strategy be programmed into the control system at the time that acceptance testing is conducted. This measure aims to add an alternative pathway to comply with the HVAC DR control requirements to allow a load management strategy that limits the capacity of variable speed compressors. Adding this alternative control strategy enables a building to implement HVAC DR controls that best fits the buildings capabilities. Allowing for successful participation in DR programs at the time that the controls are installed and minimizing a need for reprogramming after the Title 24, Part 6 acceptance tests are complete.

The alternative control strategy will be designed such that the temperature change in the zone will remain within a comfortable range.

In addition to adding an alternative control strategy, this measure aims to realign Title 24, Part 6 language so it is more consistent with how HVAC controls commonly manage loads in nonresidential buildings. Specifically, the Statewide CASE Team is making the following recommendations:

• Revise language to clarify that the demand responsive controls for HVAC systems can either be controlled through the energy management control system (EMCS) or directly through the HVAC system zone controller.
• Revise the term “demand shed control” to reflect the new reality that load management does not always call for load to be reduced or shed

Materials that the Statewide CASE Team developed when investigating this code change for the 2022 code cycle will be moved to the Future Code Cycles section of this website. Follow this link to find materials on

Relevant Documents

Measure proposals, supporting documents, and other outside references will be made public as they become available.

• CASE Study Results Report – Nonresidential Grid Integration
• Final CASE Report – Nonresidential Grid Integration
• Draft CASE Report – Nonresidential Grid Integration

Round Two Utility-Sponsored Stakeholder Meeting Materials

• Submeasure Summary – Nonresidential Demand Responsive Indoor Lighting
• Presentation – March 3 – Lighting Utility-Sponsored Stakeholder Meeting
• Notes – March 3 – Lighting Utility-Sponsored Stakeholder Meeting

Round One Utility-Sponsored Stakeholder Meeting Materials

• Submeasure Summaries – Nonresidential Grid Integration
• Presentation – Sept 10 – Grid Integration Utility-Sponsored Stakeholder Meeting
• Notes – Sept 10 – Grid Integration Utility-Sponsored Stakeholder Meeting