Much of what would be considered cutting edge technology in the energy and AEC industries today can trace its roots back to past research efforts at the Pacific Northwest National Laboratory (PNNL), one of 17 US Department of Energy labs. Take solid-state lighting, for example—the lighting class that includes LEDs. PNNL didn’t invent LEDs, but has been instrumental in accelerating improvements to the technology and encouraging its penetration into the marketplace. Few other technologies in recent years have done as much to reduce energy use in as short a time. Once full market saturation is achieved, DOE estimates that solid-state lighting (SSL) has the potential to reduce total domestic energy use for lighting by half.
Detroit, a city that is still recovering from municipal bankruptcy, is a prime example of the potential of LEDs to cut into energy budgets. When the motor city filed for bankruptcy in 2013, about half of its 88,000 streetlights were not in working order, leaving much of the city dark at night and susceptible to vandalism and a host of other social ills. The city nearly chose to replace its lighting stock with high pressure sodium lights until the Municipal Solid State Lighting Consortium, a technical advisory group backed by PNNL research, made an alternative suggestion. With PNNL’s help, the city is now in the process of replacing 65,000 streetlights with high-efficiency LEDs—an effort that will save an estimated $2.94 million annually in electricity costs and 45.6 million kilowatt-hours in energy, not to mention removing the equivalent of more than 40,000 tons of carbon dioxide from the atmosphere. And, since the replacement project began, Detroit’s crime rate has dropped 18%.
“Due in part to Detroit’s success, we are seeing LED streetlights flood the market,” says Dennis Stiles, program manager for building energy efficiency research at PNNL, pointing out that both Walmart and MGM Resorts International have pledged to replace their parking lot lights with LEDs. PNNL has helped develop many of the metrics used by the lighting industry to test and measure the performance of LEDs, a critical step in getting the technology from the drawing board to the manufacturing stage. They’ve also carried out field trials to see how well the technology fares in different applications. “We did installs in Minneapolis to see how things worked in the cold, and some in Arizona to see how it works in the heat,” Stiles says.
Leading LED Technology to Market
Technical analyses are just the tip of the iceberg of what PNNL is working on in the SSL space. “Early on, the focus was on replacement,” Stiles says. “You take out a 60-watt incandescent bulb and replace it with an LED lamp. But now, because of the way these products can be made, and the way you can design light products using these LEDs, you can rethink the way lighting is done. It’s no longer just a replacement option, it’s a completely new way of thinking about delivering light.”
LEDs are more efficient and longer lasting than other lights, but there is another important, and often overlooked, facet of the technology: they are highly controllable. They originate from microchip technology, Stiles says, and are built on a circuit board, meaning that many other functions can be embedded into LED light fixtures. That fundamental difference allows them to fit snugly into PNNL’s vision for buildings of the future—a new paradigm where every feature related to a building’s energy use, occupant comfort, security, and IT capability are knit together into a single, programmable system. “Imagine your lighting being connected and controlled as part of your larger building efficiency strategy,” Stiles says. “By connecting LEDs to more than just a power source, they can sense things like the temperature of a room, whether there is someone in the room, or whether there are 10 people in the room.”
LEDs also lend themselves to radically different design considerations that will be of interest to architects. Because they produce much less heat, they can be embedded in almost any design element, making the idea of light fixtures as distinct objects unto their own irrelevant. Rather than a ceiling with lighting fixtures hanging from it, the ceiling panels themselves could glow bright or dim themselves in response to the available daylight, user needs, and other parameters. They could change the mix of wavelengths that make up white light and their intensity to better suit the different uses that may occur in a single space at different times, for example. “You can have an architectural feature that is cool and glitzy and does many things, but also happens to put out high-quality light that better meets user needs and is extremely energy efficient,” Stiles says. “That’s where lighting is headed.”
To get there, LED lights need specialized sensors that are fully integrated with building control systems. PNNL is working on that, too.