5 minute read
Lighting and Load Flexibility
The Future of Building Energy Management
By Parker Allen
The country’s power grid faces serious challenges in the coming years, from substantial growth to the logistics of distributing power when and where it is needed. To detail the role lighting can play in our grid’s adaptation to coming challenges, LM&M spoke with Chris Wolgamott, Senior Product Manager at Northwest Energy Efficiency Alliance (NEEA). His insights are the basis for this article.
As energy demands grow and more renewable resources are integrated into the grid, building operators will need to become increasingly flexible in how they manage their electricity loads. Lighting may not constitute the largest share of a building’s energy consumption, especially with the efficiency of LEDs, but its ubiquity and potential for integration make lighting a critical piece of the power grid puzzle. Even simple lighting sensors and controls can serve as a central point in helping define and distribute energy usage across other building systems, enhancing flexibility beyond simple energy efficiency metrics.
MOVING FROM KWH TO KWH AND KW
Historically, energy efficiency and demand-side management have focused on reducing kilowatt-hours (kWh)—the total energy used. However, as we transition to a grid that draws much of its power from renewables, the focus will increasingly expand to include total kilowatts (kW), specifically to distributing those kilowatts when and where they are needed. "It’s not just about how much power is used, but when that power is used," noted Chris Wolgamott.
This expanded focus reflects the intermittent nature of renewable energy sources like solar and wind, which are not always aligned with peak demand times. By using lighting systems to spread or "flex" loads outside of these peak times, building operators can avoid expensive energy costs and reduce strain on the grid.
THE HIDDEN FLEXIBILITY IN LIGHTING
Basic lighting controls provide some ability to reduce energy usage. The institution of simple energy-saving processes like high-end trim and dimming capabilities can reduce power consumption during peak demand periods, such as between 4 p.m. and 6 p.m. Daylight harvesting can provide additional savings. These strategies should be implemented in every lighting project.
Further energy can be saved by using stored energy to power lighting. Wolgamott offered the idea of using batteries, charged during off-peak hours, to power parking lot and street lights. Doing so would prevent these lights from drawing power during the critical 4-9 p.m. peak window, when both residential and commercial energy demands overlap and renewable energy generation drops.
But, lighting systems can do more. While energy-efficient light sources like LEDs have dramatically reduced energy consumption, future savings will come not from the lights themselves but from how they are controlled.
Wolgamott emphasized the importance of digital lighting control systems in managing flexible loads. Advanced lighting controls, such as networked lighting controls (NLC) and luminaire-level lighting controls (LLLC), unlock even more possibilities through data collection and integration with other building systems.
Traditional analog systems, such as 0-10V dimming, lack the feedback necessary for true load management. Digital controls, on the other hand, allow for two-way communication between the system and the user, providing precise control and feedback on energy usage.
Europe has already embraced digital control systems like DALI (Digital Addressable Lighting Interface), but in the U.S., analog systems still dominate. However, as Wolgamott pointed out, digital controls—while initially more expensive— will provide greater savings and flexibility in the long run.
Beyond simply controlling lights, digital lighting systems can inform and integrate with other building systems to create a more cohesive and efficient environment. Systems that use networked lighting controls (NLC) or luminaire-level lighting controls (LLLC) offer a wealth of data that can inform everything from HVAC to space utilization.
By using lighting controls and occupancy data, building owners can predict and manage their energy needs more precisely, shifting consumption away from peak hours to times when energy is cheaper and more abundant. This doesn’t just help utilities—it can lead to substantial savings for building owners, who can reduce both their overall energy usage and avoid expensive demand charges. Furthermore, utilities often offer incentives to building owners to enable load flexibility.
The benefits go beyond energy and cost savings. Features like asset tracking, space management, and improved safety can drive the decision to invest in advanced lighting controls, even if energy savings are not the primary concern. As Wolgamott noted, "Energy savings help pay for the system, but the non-energy benefits help sell it."
As we move toward a future reliant upon renewable energy, flexible load management will become increasingly important. Lighting systems offer a unique opportunity to manage energy use in smarter, more efficient ways. By embracing digital controls and advanced energy management strategies, building owners can reduce their energy costs, improve system reliability, and contribute to a more sustainable energy future.
