Connectivity has become a driving force in our daily lives. Information we once had to seek out using card catalogs and periodicals indexes (remember those?) is now available almost instantly with a voice search on a smartphone. Printed road atlases gave way to dashboard GPS systems that, in some cases, can literally steer a car in the right direction. Now, developers are seeking to make that connectivity more useful by increasing its speed and carrying capacity, and the humble streetlight is becoming a valuable asset in this process.

Technologies such as 5G cellular communications need a place to land, as do all the sensors being developed to detect and transmit roadway information. Streetlights are ubiquitous and offer direct access to electrical power, especially in urban and suburban locations, so they are a critical component in cities’ digital infrastructure. From monitoring weather and safety conditions to aiding the deployment of autonomous vehicles, devices added to streetlights are set to become more numerous and important over the next decade.

Streetlights are an important component in cities’ digital infrastructure. Adding sensors for monitoring weather and safety as well as for aiding the deployment of autonomous vehicles brings intelligence to streetlights. 

Opportunities in the LED transition

Bringing intelligence to streetlights isn’t a new idea. Manufacturers started adding sensor options to fixtures as the introduction of LEDs began a mass movement toward highly efficient lighting technology. 

What’s new is that the move to 5G cellular systems is providing the speed and bandwidth needed to enable new applications, including aiding the development of autonomous vehicles, which will be using 5G to communicate with other vehicles and the environment. Additionally, cities could use smarter streetlights to monitor real-time traffic and roadway conditions more easily.

“The street lighting infrastructure is the backbone of smart city initiatives and technology,” said Ben Gardner, president of Northeast Group, a Washington, D.C., consulting firm focused on digital technologies for cities and utilities. “This entails LED and smart street lighting deployments. It also encompasses sophisticated sensors and video applications in the streetlight infrastructure. These could be environmental sensors, smart parking and other applications, or small cells to enable the deployment of 5G across a city.”

Because of these new opportunities, Gardner said streetlights are also becoming financial resources for towns, cities and utilities, depending on who owns them. 

“Streetlights are vertical assets in a city that can be leveraged for multiple applications,” Gardner said. “They are a particularly attractive piece of infrastructure on which to attach various types of sensors, and also small cells for 5G connectivity. Streetlight poles are now significant revenue generators.”

Signify (formerly Philips Lighting), Bridgewater, N.J., is a leader in this area. Martin Stephenson is head of professional systems and services for North America, as well as president and CEO of Signify’s Canadian division. He said the appeal of smarter fixtures begins with savings cities can see from the beginning, on top of the reduced energy use of LED lamps versus old-school metal halide options. Smart streetlights can be monitored and operated remotely, and the accompanying dimming functions can cut operating costs by an additional 15%–20%, Stephenson said. Savings can begin during installation.

“We have a feature called a service tag, which sits within the luminaire itself, and by scanning this QR code, you have the ability to identify the actual luminaire and ensure that it’s positioned in the right place,” Stephenson said. “And we have the ability to build databases of the installed base to allow a contractor to understand which asset they need to go to, for example, if there’s an issue with a nonperforming luminaire—maybe that’s because the pole has been hit. From a contracting point of view, it has the ability to streamline your installation and really manage an asset database.”

Real-world applications

Beyond improving basic lighting operations, Signify’s sensor and applications options can generally be categorized into three major buckets. Public safety features can include video or still cameras, noise and motion monitoring and the ability to over-­illuminate specific fixtures to, for example, aid law enforcement officers working in or around a crime scene. 

Environmental monitoring includes cameras and sensors to help road crews track rain, snow and ice accumulation and keep an eye on stormwater flows. And traffic management applications could include monitoring traffic flow and helping drivers locate available parking spots. Now, Stephenson said, there’s a growing interest in upping the ante in all these areas through 5G implementations.

“By this, we’re talking about wireless, digital kiosks, smartphone applications and connected vehicles,” he said. “That will be the demand we’re working with a number of towns and cities on now, to really understand what their vision is for the future.”

One of those cities is Mesa, Ariz., which has adopted the company’s BrightSites program to bring Wi-Fi to its downtown areas. This system doesn’t need fiber wired to each pole—instead, it uses cellular nodes installed in the fixture to create a free-to-the-public network.

In Mount Vernon, N.Y., Signify’s Interact connected lighting system was added as an upgrade to a number of the city’s RoadFo­­­cus streetlights. Like many newer fixtures, Mount Vernon’s streetlights feature Zhaga sockets—a standardized communications connector used by many LED luminaire manufacturers—which made adding new intelligence easy. Now, in addition to smart dimming that dials down fixture output during low- and no-traffic periods, managers can monitor neighborhood temperatures and noise levels. So, for example, the city can detect and act on leaf blowing that exceeds noise levels in local ordinances.

In Mount Vernon, N.Y., city managers use smart dimming that dials down streetlight output during low- and no-traffic periods.

Tracking the future

New smart road technologies that take fuller advantage of 5G capabilities are now on the drawing board. When their developers want to begin testing them, they often turn to the Virginia Tech Transportation Institute (VTTI) located near the Blacksburg, Va., campus. Developed about 35 years ago to address transportation safety issues, the facility has become an international test bed for road and vehicle technology applications. Its Virginia Smart Roads test tracks include a 2.5-mile highway and sections designed to mimic urban and rural locations, along with an intersection designed to Virginia Department of Transportation standards.

Designers have put a lot of attention into detail, with features including rain- and snow-making capabilities and realistic design elements.

“The rural section is designed to 1965 highway standards, so there’s a lot of horizontal and vertical curvature, and a lot of areas where the striping is not so good—and that’s all meant to represent conditions you would normally see out in the field,” said Mike Mollenhauer, director of VTTI’s division of technology implementation. “When we bring technology to be tested here, we want to test it under the conditions that it will be operated in the field.”

Also featured are reconfigurable lighting systems that can be set up to represent 95% or more of what’s deployed in the United States. This allows for safety testing, among other efforts, to determine lighting needs to ensure visibility of safety vests at night.

VTTI researchers have worked with 5G technologies for about four  years, according to Mollenhauer, and are now establishing a core team to support testing on the track. This includes establishing a connected vehicle environment, including dedicated short-range communications used in vehicle­-to-vehicle and vehicle-to-­environment information exchange. Proof-of-concept work is underway to see if 5G systems can be fast and reliable enough to support safety-critical applications. Mollenhauer noted this will require high bandwidths capable of supporting the LiDAR, radar and camera data needed for technologies such as autonomous vehicle operation.

“We need to be able to get that data into a place where it can be operated on—meaning you can run machine vision, artificial intelligence and machine learning algorithms to get outputs, and then to get that back to where it can actually be used,” he said, explaining the process required to make the promise of 5G actually work in active roadway applications. “Having that low-latency, high transfer speed and high bandwidth capability really helps.”

VTTI now is working with digital communications leader NEC, Irving, Texas, on just such an approach to creating a roadway warning system. NEC installed cameras and video analysis equipment on test track traffic signal poles with analytics technology that can detect, categorize and track vehicles, pedestrians and bicycles around intersections. 

They also incorporated a cellular vehicle-­to-everything communications system that notifies vehicles and pedestrians of safety information and warnings. Analytics were based at a VTTI data center about two blocks away, using 5G cellular communications.

“We did prove that is a viable means to get the data back and forth, and to do it at very low latency,” Mollenhauer said. 

“Low latency” means there was minimal lag time in the data transmission, which is obviously very important in the traffic-­warning applications NEC was studying. 

“That sort of stands as an example for how that model can be applied if we were to take it to an urban area and try to apply it to intersections where maybe you don’t have a fiber run already,” he said.

Stay tuned

Obviously, these communications technologies are maturing rapidly, and products such as smart streetlights are becoming a more common presence along roads and highways. So, what new uses might we see in the next five years or so? Gardner said capabilities will continue to expand, but broad adoption could take longer.

“Smart street lighting has already scaled into the millions of endpoints, and we will continue to see strong growth over the next 5–10 years,” he said. “As additional smart city applications prove their business cases, we will see those deploy as well, although, for the time being they are mostly still in pilot and proof-of-concept stages.”

stock.adobe.com / silvae/ TripleP Studio / signify