NLC V5.2 Technical Requirements: Making Way for Lighting and Thermostat Integrations 

What’s Changed in NLC V5.2

The V5.2 revision aims to strengthen our specification, supporting a shared framework for quality products that can align among manufacturers, utilities, program administrators, and other industry stakeholders.

The main changes in the revision help Qualified Products List (QPL) users to maximize energy savings in small and medium sized buildings, by installing NLC systems that…

• Report their energy-saving configuration settings in a standardized manner, and
• Integrate with smart thermostats to provide occupancy data.

With standardized configuration reports, utility programs can easily ensure that NLC systems have been set up properly. Studies have shown that proper NLC configuration is essential for saving energy.

With occupancy data from NLC sensors, thermostats can automatically save HVAC energy whenever spaces are unoccupied. This saves energy in buildings with highly variable occupancy such as schools; and even in buildings with regularly scheduled occupancy such as retail, if nobody ever programs the thermostat to match the schedule.

These capabilities will enable energy efficiency programs to better serve small and medium sized commercial buildings, which are a major focus for many programs. Small and medium sized businesses and buildings are notoriously “hard to reach” compared to large buildings, but this sector is important for addressing equity and high potential energy savings. By using occupancy data from lighting controls to inform thermostat operation, integration can unlock energy savings of 8% to 21% HVAC energy reduction while also delivering lighting energy savings from the retrofit.

By surfacing these capabilities in our technical requirements and QPL, we are enabling the market to choose NLC products that can save substantial HVAC energy in addition to lighting energy.

Here’s how the industry benefits

• Save more energy and improve building performance through NLC-thermostat integrations
• Utilities will have more confidence in energy savings from NLCs with standardized configuration reporting (ANSI NEMA C137.9)
• Show utilities that lighting retrofits with NLC-HVAC integration can save substantial energy, even with a first generation LED baseline.
• Improve the ability to compare and select products on the QPL.

In short, this update provides clarity around the latest NLC advancements and enables the market to collaborate to achieve more energy savings through NLC-HVAC integration via thermostats. It’s in our mission: the DLC sees NLC systems and building integration as a path to more energy savings and decarbonization. Our goal with this update is to make it easier for stakeholders to choose the right systems for their building and to enable more utility incentives to encourage the installation of those systems.

Cybersecurity and NLCs

Cybersecurity requirements have not changed in this revision. As smart buildings continue to advance, the bridge between a building’s physical systems and its IT infrastructure becomes more important. Foreseeing this trend, the DLC introduced its cybersecurity requirements 6 years ago and began implementing them in NLC V5.0 starting in 2022. Although we did not make any requirement changes in NLC V5.2, cybersecurity continues to be one of the focus areas of the NLC program.

Thank You to our Stakeholders

We are grateful to everyone who commented and contributed to these requirements. For more information on integrating NLCs and building systems focused on large buildings, please review our NLC-HVAC Toolkit and consider attending the DLC Summit 2026, which is themed “Next Gen Lighting: Controls, Integration, and the Environment.”