How Efficient Are Your LEDs? Check the Color

Share this article:

The energy savings of light-emitting diodeslight-emitting diodes (LEDs) depend strongly on the color of light they produce, an EPRI study finds.

In recent years, utility energy efficiency programs have achieved energy savings by encouraging customers to switch to LEDs from fluorescent, halogen, and other available technologies. With the introduction of color-tunable LEDscolor-tunable LEDs, utilities find it more difficult to predict savings, because their power consumption varies by color. Their applications can include replicating the sun’s daily color shifts and providing light at wavelengths specific for indoor agriculture.

To specify how color-tunable LEDs may affect customer load, EPRI lab-tested 36 products in three categories: dim-to-warm, tunable white, and full color. For full color and tunable white products, the “luminous efficacy” ranged widely across different colors. Full color products were less efficacious at blue, purple, and red, and more efficacious at green and yellow. Dim-to-warm products generally declined in efficacy as they were dimmed.

“This research shows that color-tunable products have wide performance ranges,” said EPRI Senior Technical Leader Frank Sharp. “As more of these products are deployed, utility planners need to understand their variable efficacy profiles to make effective use of them in efficiency programs.”