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When was the last time you gave your business’s exterior commercial lighting serious consideration? Exterior commercial lighting can seem like a “set it and forget it” expense because the cost is generally regarded as a necessary and fixed part of doing business. That may have been the case in the past, but the landscape has changed dramatically. With the decline in price of high-quality LED luminaires and the increased availability of reliable outdoor sensors, it’s time to invest in exterior lighting retrofits.

Many California businesses have implemented dynamic adaptive lighting designs that offer 30% to 75% energy savings over traditional systems, according to research conducted by the California Lighting Technology Center (CLTC).¹ In addition, there are many rebates available to help businesses successfully implement adaptive exterior lighting.

The essentials of adaptive exterior lighting
Adaptive exterior lighting performs as its name suggests: Illumination levels adjust according to the changing needs of the application, using integrated or remote sensors, or time-based schedules. Some systems combine both strategies. Optimal applications for adaptive exterior lighting include parking lots, parking garages, low-traffic walkways, privately owned street lighting, facility loading docks not in use during night hours, canopy lighting and specialty applications, such as sign lighting.

Luminaires paired with motion controls deliver maximum light levels during occupied times and then lower the illumination levels during low-traffic periods. As a result, when illumination is not necessary in unoccupied areas, lighting energy use can be significantly reduced.

Some adaptive exterior lighting systems include time-based scheduling. These systems adjust light levels during predictably active and inactive periods, or during times of night when less light is needed (dusk, darkest part of the night or just before dawn). This may seem like a simple practice, but it is not yet widely applied even though it has been demonstrated as a highly effective strategy to reduce energy use. According to the previously referenced CLTC research, studies found that a time-based approach, sometimes called curfew dimming, was able to generate up to 75% energy savings compared to traditional exterior lighting systems that do not include scheduling controls.

Photocontrols, which extinguish lights during daylight hours, also play a role in the adaptive lighting strategy but are currently in common practice. In most commercial applications, time-based controls such as astronomical time clocks can be used in lieu of photocontrols, provided they serve the same function.

Pair controls with LED luminaires
LED luminaires provide advantages over less efficacious options and pair well with controls. LED lighting is a rapidly evolving technology that uses semiconductors to convert electricity into visible light. LED lighting uses significantly less energy than traditional options, dims well when specified properly, lasts far longer and turns on and off instantly. Lowering lighting power levels by dimming or switching to “low-mode” can extend the life of the LEDs. The more time the luminaire spends in “low mode,” the longer the potential life of the device.

Some luminaires are equipped with fixture-integrated motion sensors. The integrated sensor can be included at the time of specification with minor additional cost. This takes the guesswork out of pairing external sensors with groups of luminaires. Larger installations may benefit from the use of a networked lighting control system in addition to sensors. This advanced option connects all light points into one system, which collects data about energy use, the operating conditions of the luminaires, and other data. This can be used to adjust the system for optimal usage over time.

Adaptive exterior lighting at work: LED wall packs with integrated sensors
Wall packs are frequently used to illuminate building perimeters. These wall-mounted fixtures illuminate areas in close proximity to a building, increase security and help visitors and employees find their way after dark.

According to CLTC, existing wall packs typically use high-intensity discharge light sources, such as high-pressure sodium and metal halide lamps. Businesses can reduce energy costs by choosing more efficacious sources, such as LEDs, and equipping wall packs with motion sensors, photosensors or time-based controls. This can reduce their energy use dramatically. In a case study focusing on LED wall packs at the University of California, Davis, the measured luminaires remained in low mode for 80% of the night.² Even in low mode, the luminaires provided enough illumination to see the area while using a fraction of the energy required by the traditional system it replaced. The wall packs in the study reduced the energy use by nearly 90% over the previous non-dynamic system. In low mode, the units used only 14 W. This replaced a system that used 189 W, all night, regardless of whether the light was needed.

Rebates are available to reduce first costs
To help reduce the upfront expenditures of these installations, upgrades or retrofits, rebates are available for energy efficient lighting options.

Successful projects start with a commercial lighting contractor 
The options cited above are a few types of adaptive exterior commercial lighting that are available to businesses. In order to determine and implement the lighting and controls you want, consult an experienced commercial lighting contractor or lighting designer. An expert can help to select an appropriate system for your application and help you secure lighting rebates.

To learn more about different types of adaptive exterior lighting systems and how they can maximize energy savings for business owners and managers, download Pacific Gas and Electric Company’s free guide, “Exterior Lighting Solutions for Businesses.”

Sources:

1. California Lighting Technology Center
2. California Lighting Technology Center