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The Spotlight is on Streetlights as IoT, 5G and Smart Cities Emerge (and Converge)


The modern streetlight is undergoing a massive transformation from high-pressure sodium lamps to high efficiency LED designs. Lighting form factors and control systems will undergo a once-in-a-century transformation that will add wireless interconnectivity, intelligence and a host of environmental sensors and video imaging capabilities. As a cornerstone of many municipal plans for the smart city of tomorrow, questions about how the new waves of connected streetlight data will be accessed, stored, secured and managed will need to be addressed. 

Hundreds of millions of streetlights will accomplish their traditional missions of illumination this evening, but at the same time they are being considered for much more. Their individual positions within an upgradeable grid on nearly every city street and collective formations within municipal districts are unique among public sector assets. They will soon be leveraged by a variety of public (and private) interests at the confluence of a massive upgrade to more efficient LED lighting. They will kickstart the evolution of many smart city initiatives driven by 5G wireless technology advances and IoT applications. Some will see these upgrades as inevitable and desirable. Others will see the streetlight as the centerpiece of a big data movement with implications far beyond their original scope … as yet another example where technology may have outpaced public understanding or municipal oversight. By any measure, the centuries-old concept of what a public streetlight is (or could be) will never be the same.  

In the Beginning: A Single Purpose        

From the earliest attempts to harness volcanic gas or burning oil, humans have been lured by the prospects of squeezing more useful hours from each day by lighting up the night. Municipal streetlights have been illuminating the paths of travelers for hundreds of years now, with many urban cores operating 24/7 as cities that never, or rarely, sleep. 

Centuries ago, city governors would mandate the use of oil-based lamps on the street-facing walls of city homes to make nighttime a less menacing part of the daily cycle. As public street lamps were deployed, designs evolved from weak, overhead flames burning from wicks soaked in fish oil to increasingly more advanced designs. Innovative, silver-plated copper reflectors which could mechanically focus and steer a flame’s light became popular in Paris during the 1760s. Decades later, gas-powered lamps reached the mainstream in England and introduced a brighter network of ‘artificial suns’ along with a new job title: lamplighter.  

Russian engineer Pavel Yablochkov introduced an electric streetlighting approach in Paris which used carbon arc lamps featuring alternating current. By 1879, Thomas Edison’s company had demonstrated a 12-unit electric streetlighting system in Cleveland, Ohio, which defined a new kind of public utility with streetlighting at the core. In the 1880s, Barcelona commissioned the production of candelabra lampposts from the acclaimed Spanish artist, Antoni Gaudí. Many of these still stand today and commonly draw tourists in for Instagram selfies. As cities around the world installed their own gas lighting grids at the turn of the century, designs for lampposts ranged from the practical to the ornate. British manufacturer, William Sugg & Co, produced a catalog with dozens of models including the Metropole, the Lambeth and the Westminster, each with matching lamp and pedestal options for posts up to 20 feet tall. Londoners will recognize the famous twisted fish pedestals of this era as they walk beside the River Thames today. 

In less than a century, urban planners migrated from gas-powered lamps that were often maintained by police departments to fully-electrified lighting systems leveraging matrices made up of thousands of lampposts stationed alongside city streets. In modern times, we are witnessing the next transition: from high-pressure sodium (HID) lamps, which are still the most common type of streetlight, to more efficient LED solutions.  

Public sector streetlighting is often the largest fixed expense from a city’s general fund each year. That’s one reason why the lure of LED-based solutions promising substantial operational savings is such an easy door opener among city administrators.    

From a Network of Poles to Networked Connectivity   

As public utility organizations work with their trusted vendors to address the migration to LED-based lighting, all manner of related technology advancements are being introduced into the mix. The height, location and elevation of a municipality’s streetlights offer a promising locale for smart traffic sensors, high-definition security cameras, public Wi-Fi® hotspots, environmental sensors, 4G/LTE and 5G small cell base stations, solar panels and IoT nodes for applications that have yet to be developed.  

Streetlights are naturally positioned along streets and roadways — where the people are. This is significant real estate indeed! The small squares of land where utility poles and streetlights are anchored might be among the most remarkable plots of land on a square foot basis in any city. For centuries, utility companies have secured easements in order to run wires, cables and pipes and install related infrastructure assets. Electric, gas, telecom, water, sewer and cable television companies often utilize public easements to connect services to citizens. Public easements allowing utility infrastructure on private land combine with city-owned property to create a matrix of elevated poles which are ideal for enabling wireless interconnectivity and as gateways to public networks. Their location and availability for co-located technology has thrust municipal streetlights into the role of catalyst for getting smart city initiatives off the drawing board and into the real world.  

Historically, the landscape of streetlights has been without widescale network connectivity or universal standards. Urban leaders often face expensive operational costs and maintenance burdens, along with less-than-stellar energy efficiency outcomes. Municipalities are now starting to publicize plans and proposals for smart city IoT programs which promise cost-effective solutions for managing public assets and interconnection among neighboring communities. In both state-run utility agencies and in highly-regulated public/private agencies, the concept of streetlights as enabling tech for smart city projects has a great deal of momentum. Connected streetlights are projected to decrease the cost of municipal lighting, and offer advanced capabilities that were unthinkable a generation ago. City managers will be able to manipulate the illumination levels throughout the day, increasing them gradually as sunset approaches … like a giant living room on a dimmer switch. Spikes in vehicle traffic, dynamic changes in weather conditions, antisocial behaviors and public gatherings at major events could all be supplemented with increased lighting from smart city platforms (SCPs). Imagine a future where on-demand, color-coded pathways of city luminaires could be switched on in an instant to provide visual cues for evacuations during an environmental emergency or directional beacons for first responders arriving on the scene of an accident.   

Cities across the world have been rolling out LED upgrade projects with an eye on migrating smart city objectives into their long-range plans. Miami, Paris, Madrid, Los Angeles, Jakarta, Montreal, Birmingham (UK), Dongguan (China), Buenos Aires and Milan have been particularly aggressive in deploying connected LED streetlight updates. 

Towards an IoT-enabled Smart City

You don’t need to know your acorns from your cobra heads to understand that a connected grid of LED streetlights could also offer a host of parallel benefits to city managers, police departments, emergency services organizations and citizens when they are enhanced with additional functionalities that leverage their location, manageability and access to power. (Note: acorns are the globe-style light fixtures that sit atop light posts and project a nearly omni-directional light pattern, while cobra heads are the overhead configurations that extend to the end of gradually-arced arms and direct their beams down to roadways and streets).   

By their very definition, connected streetlights are just that. Connected. This could be achieved via Ethernet, but most modular architectures will mandate wireless communications modules such as LoRa® for long range interconnectivity among adjacent lights and connection to municipal SCPs, as well as Bluetooth® for short range connections at the device level or at the pole level. 4G/LTE and 5G modules introduce another secure avenue for connecting to local government systems, maintenance databases and over-the-air (OTA) software and firmware update solutions while Wi-Fi technology adds a hybrid wireless option and potential public hotspot capabilities to the metro network engineer’s toolbox. 

A weather-proof OEM streetlight enclosure designed for LEDs that also includes a full spectrum of wireless connectivity options is just the baseline foundation. Narrowband IoT (NB-IoT) nodes will also find a home in these architectures. So how about sensors? 

There was a time when city managers recorded temperatures from a singular location, like an airport. That seems like the dark ages now. Consider temperature sensors on every street corner, or in most streetlight enclosures around town. You would have unprecedented heat map capability across every node with a wide variety of use cases. Now add humidity sensors, vibration sensors to monitor seismic activity, sound sensors, photocells, and all kinds of motion sensors to monitor traffic patterns and densities from pedestrians, bicycles, motorcycles, cars, trucks and buses. Sound sensors could listen for the unique frequencies of breaking glass and the screeching of brakes to direct first responders to accident scenes before the first emergency call is initiated. The magic that many propose happens when secure, open access to this sensory data is available to third party developers so that they can create parking apps, real-time air quality indexes and smart traffic management systems.   

Cameras and audio? 4K video cameras are an obvious modular option in the age of 5G. High definition IP cameras, image sensors and microphones can be used to link real-time feeds to media storage systems at city hall, within police departments or directly to emergency services organizations. Dispatchers could deploy first responders with real-time video insight into the emergency environments they will encounter … before they arrive. Video could be archived for designated periods and stamped with the precise location of each overhead video node. 

Many more configurations are being dreamed up by smart city ecosystem designers. Alternative power configurations from solar panels and power-over-Ethernet (PoE) could accommodate new product integrations without major installation outlays. Electric vehicle (EV) charging stations could leverage the access to power sources in the most convenient light pole locations. Smart city cameras could help reinvent parking control in urban cores with highly accurate management and billing capabilities — and without the maintenance burdens of old school parking meters. Real-time vehicle flow data will interface with IoT-enabled traffic lights resulting in better traffic conditions, reduced wear and tear on vehicles and reduced emissions. That’s a win-win for drivers and the environment! On-pole digital signage in downtown entertainment districts and leased mounts for cellular network antennas and small cells could be revenue-generators for a city at the same time LED lighting is slashing their energy bills. That is a powerful pitch. And one that gets more realistic with each add-on that can be co-located during the mass migration LED lighting. 

When a Streetlight is No Longer a Streetlight 

Few would argue that the potential to use smart city technology (by way of connected streetlights) to enable apps for visually impaired pedestrians, create safe routes for joggers or deliver spatially aware data to locate missing children would be anything less than 100 percent positive. 

But with any great leap forward that involves personal data and video technology, the question of who has access to the data and video (and why) is sure to follow. And that question is sure to be enhanced by justifiable concerns over surveillance and privacy. 

Question: Have you noticed that it’s difficult use the word surveillance in a sentence that conveys a positive message? Once it is used, there’s usually a lot of explaining to do. 

It’s also very difficult to describe the amount of privacy that one should expect on city thoroughfares or the extent of anonymity that one should assume in a public venue, so I won’t even try. That’s the job of urban planners, community leaders, politicians, privacy advocates, government agencies, police departments and city councils among others. It’s likely to vary widely from person to person. From city to city. And from country to county. 

While smart cities are being imagined by technologists, connected streetlights are increasingly stealing the spotlight and the public’s concern. The word inextricably is an adverb that means “in a way that is impossible to disentangle or separate,” and it is a great word to consider here. Connected streetlights are inextricably connected to many fast-rising applications that are not easy for the public to understand beyond the buzzwords. From the vehicle-to-everything (V2X) communications of autonomous vehicles and traffic management systems to 5G video networking and IoT-enabled environmental monitoring, the attractiveness of leveraging the smart, connected streetlight infrastructure cannot be understated. 

First-mover municipalities have found that many citizens only discover video capabilities in streetlights after pilot programs have commenced, regardless of their pre-launch hearings and public outreach campaigns. In some cases, a law enforcement agency’s request for access to video footage will spark interest among community members. That’s often too late. A backlash is inevitable. At that point, streetlights are not streetlights. They are clandestine video spy towers. License plate scanners. And facial recognition machines.   

We are in a time and place not unlike the camera-enabled retail UAV (drone) sector about seven or eight years ago. There was a pent-up demand by real estate agencies to use drone video footage and photography to help sell houses. Seemingly harmless. But the technology was way ahead of the policy. The U.S. Federal Aviation Administration (FAA) and a group of the largest real estate agencies seemed to agree with an ever-growing coalition of city managers that commercial applications for drone use needed to be banned (temporarily) until laws, rules and policies could catch up. They seemingly said, “We did not anticipate the widespread availability of this technology, and we need time to consider how it should be managed.” It took several years for legislation and regulation and education to catch up with the technology.   

What’s Next for Connected Streetlight OEMs? 

As municipalities consider the wave of advanced capabilities that can be embedded in smart city streetlights, they will exchange best practices. Cities don’t compete against each other when it comes to technology disruption. They are eager to share.  

As they develop regulations and transparent policies (and put them in writing) related to video capture and storage, data access protocols, public safety and the digital rights of citizens, the interest in deploying some form of connected LED streetlights as a catalyst to smart city programs will rise. 

Commercial and industrial property owners, office parks, universities and other private entities with large parking lots, loading docks and campus environments are free to seek out innovative solutions that include overt security applications (meaning: surveillance). These private installations may not have the vast control capabilities of citywide installations, but they are worth studying as pure technology testbeds.   

Meanwhile, the cost savings from LED-based systems is too great for cities to ignore. The unprecedented LED upgrade cycle in the public sector will continue, and with it the opportunity to create modular streetlight architectures that can accommodate new services as they become accepted (and acceptable) along the evolutionary path to smart cities. 

Microchip’s technology experts can help you better understand connected streetlights and embedded wireless connectivity, smart embedded vision, mobile broadband gateways, lighting technology, Power-over-Ethernet (PoE), sensor integration, microcontroller selection, power and energy consumption, onboard memory, FPGA design, security and other key considerations for smart city streetlights.  

Check out a recent connected streetlight customer success story here or click the links below to learn more about Microchip’s offerings.

Microchip Trust&GO LoRa

Microchip WLR089U0 LoRa Module

Microchip LoRa Solutions

Microchip Bluetooth Low Energy Modules

Microchip Security Solutions

Microchip Memory Solutions

Microchip ATECC608B Secure Element

Microchip Microcontrollers

Microchip MOSFET Gate Drivers 

Microchip Smart Embedded Vision 

Microchip Power-over-Ethernet (PoE)

Tim Bresien, Dec 10, 2020