The humble streetlight is the backbone of the modern smart city

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On a Paris street in the late 19th century, the first-ever electric streetlight flickered to life. Now, nearly 150 years later, the electricity coursing through street and traffic poles powers a lot more than just lights.

In recent years, the humble streetlight and traffic light have become the backbone of the modern smart city, housing a bevy of sensors, communication devices, cameras, and other technologies used to help digitize the streets. The fact that so many such posts already exist—New York City has over 315,000 streetlights, for example—makes them an ideal jumping-off point for installing “smart” add-ons.

“For years, it was the dumb piece of infrastructure—it’s like nobody wanted to manage it,” Ian Aaron, CEO of streetlight-focused tech startup Ubicquia, told Emerging Tech Brew. “Now all of a sudden, the cities are realizing, ‘Wow, I’ve got a streetlight every 50 meters.’ It’s eight to 10 meters high, so it’s perfect for telecom equipment. Oh, and by the way, there’s already power there.”

Let’s take a look at five key smart-city technologies that municipalities are tacking onto lampposts.

Electric vehicle charging

EV adoption is accelerating in the US, but for people who live in densely populated areas, the question of where to charge an electric car can get tricky. In 2021, only 9.7% of households in US cities had access to a public EV charging station within a five-minute walk of their home, per Mobilyze research.

Some cities and companies are hoping to address this issue by building EV chargers into—you guessed it—existing lampposts.

In New York, for example, the seed-stage startup Voltpost is working to retrofit some lampposts into charging locations as part of an NYC Department of Transportation pilot. The city is looking to potentially roll out 10,000 curbside EV chargers by 2030.

• Voltpost also received a grant from the Michigan Economic Development Corporation to provide a demonstration at the Detroit Smart Parking Lab.

Luke Mairo, COO and co-founder of Voltpost, told Emerging Tech Brew that one of the main issues with EV-charging infrastructure is finding urban space where you can dig into the ground.

“[Standalone chargers] require you to dig up the sidewalk and get all the permitting involved in that, which is both [time-intensive], but also incredibly costly to get done,” he said. “By doing this as a retrofit that leverages the existing infrastructure, we can totally undercut, just remove that piece of the equation.”

The 29,312-person city of Melrose, Massachusetts, embarked on a similar pilot in April 2021, in partnership with National Grid. So far, it has installed 15 pole-mounted charging stations on nine utility poles in the city.

Lidar sensors

Lidar is most well-known for enabling pretty much every non-Tesla AV to “see,” but off-car lidar sensors installed in streetlights could be helpful beyond AV use-cases.

Startups like Velodyne Lidar, which specializes in lidar sensors, are linking up with companies like LG and Seoul Robotics to bring sensors to streetlights.

Christina Aizcorbe, VP of government affairs at Velodyne, told us that lidar’s non-AV applications could include changing traffic signals so emergency services could travel through, reducing the amount of time vehicles idle at intersections, and improving foot-traffic conditions in areas with fewer cars.

• The tech could eventually be utilized in V2X communication, signaling to AVs warnings of potential road collisions at intersections before they happen.

“Some cities are using it to activate their signal to make sure that a pedestrian waiting at a corner may be capable of walking across the road and the speed it would take to cross the road in that set time, we’ll keep that light red until the pedestrian is able to make it across,” Aizcorbe said.

Velodyne positions its lidar sensors on top of traffic lights. The sensors operate at night and in low-light conditions and cover a 360-degree radius, meaning only one sensor is needed per intersection.

The company is currently piloting its tech in cities like New Brunswick, New Jersey; San Jose, California; and Austin, Texas. Austin Wilson, Velodyne’s senior director of global business development, said via an emailed statement that it has deployed 68 installations of its tech in 20 cities across four continents.

Air-quality sensors

Cities are also experimenting with strapping air-quality sensors to lampposts in an attempt to better monitor pollution and emissions and potentially improve the health of residents. These sensors can be installed alongside other in-demand tech, like efficient LED lights or tech designed to help reduce traffic.

Several startups have emerged to provide air-quality sensors to cities, and one example is PurpleAir, which has sold thousands of sensors in the US and has partnerships with cities like Louisville, Kentucky, and Austin, Texas.

• The company claims to now have a global network of ~24,000 sensors.

In Colorado Springs, Colorado, two city pilots were conducted to test adding new ozone and particulate sensors to streetlights. The pilots began with remote-controlled LED lights and weather data collection, and officials are now looking to conduct a pilot using air-quality sensors from Clarity Movement on six streetlights throughout the city as well.

Colorado Springs hopes to have the hardware on hand by the end of this year, Samantha Bailey, the city’s sustainability coordinator, told us in an email.

• It plans to kick off the pilot—which will last for the lifetime of the sensors, about two to four years—in the first half of 2023, she said.
• The program is modeled after an air-quality program in Denver called Love My Air.

Surveillance video

For better or for worse, lampposts are also ideal places for the installation of surveillance tech. With streetlights on every corner, cities are outfitting many of their intersections with CCTV cameras in an effort to capture crime, traffic crashes, and monitor crosswalks.

The tech has drawn criticism due to its potential use by law enforcement, especially when such cameras are paired with additional surveillance tech, like facial-recognition technology.

One example: The city of San Diego, California, experimented with streetlights fitted with surveillance cameras back in 2017 in an attempt to improve congestion and traffic flow, but faced criticism after law enforcement began using the cameras to help solve crimes in 2018.

• The tech San Diego developed for its 2017 experiment was eventually sold to Florida-based Ubicquia.
• The company now sells a device that mounts to the top of lampposts and is capable of capturing dozens of hours of video, according to Ian Aaron, CEO of Ubicquia.

“Where you have people and where you want cars and analytics, you typically have pedestrian traffic, which is where you want wi-fi access,” Aaron told us. “This is the value of the streetlight.”

Aaron said Ubicquia operates in over 74 different locations in the US.

5G

Prior to 5G, cell phone communications were primarily supplied from cell towers and large antennae by telecommunications companies like Verizon, AT&T, and T-Mobile.

But 5G has changed much of the old approach to building cell phone infrastructure. Low- and mid-band 5G still use cell towers to propagate their signals across distances, but the ultra-fast mmWave 5G can only travel short distances, requiring more connections closer together.

Because it would be financially and logistically infeasible to build all of the cell towers needed for mmWave, some telcos have opted to attach their phone cells to traffic lights and lampposts. They’re already there and much closer together than existing cell towers, so the setup is a no-brainer.

“What we really need are data connectivity and power,” Erik Varney, managing director of telematics and industrial IoT at Verizon, told Emerging Tech Brew.

“Well, we know there’s power there, obviously, because they’re controlling a light. So usually, it’s just data connectivity, which is typically there on a streetlight as well, because they have some sort of communications already pulled into that and they’re usually hollow. We want to make sure we’re covering population—and there’s no better place to cover population than intersections,” he added.

So far, Verizon leads the pack in 5G small-cell deployments, with over 30,000 units deployed nationwide.