Street lights graphic

Lighting the smart city

With so much more to offer than just simple illumination, how far can smart lighting go?

Anyone walking past New York’s iconic Flatiron building last autumn might have spotted people talking to a street light. It’s not the first time this has been seen in New York, but it would have been the first time the street light actually talked back. As part of GE’s intelligent street lighting project, a demonstrator lamppost, equipped with a digital screen and speakers, surprised passers-by with the latest weather forecast and tourist information.

While this is unlikely to be exactly how ‘smart’ street lighting will work in the future, the demonstrator gave an entertaining glimpse of what is coming. It is likely that through a network of LED (light-emitting diode) lights fitted with cameras and sensors, our future cities will be able to give us real-time updates on where to park, how to avoid traffic jams and which parts of the city are overcrowded, as well as calling the emergency services when trouble arises.

GE is already running two pilots to see what impact intelligent lighting could have. These were launched in 2015 in Jacksonville, Florida and San Diego, California. In 2014, San Diego became the first US city to widely use GE’s networked LED lighting fixtures, deploying 4,000 of the smart street lights. David Graham, San Diego’s deputy chief operating officer for neighbourhood services, explains that the primary impetus for the move was saving energy - the city has adopted an ambitious climate action plan, including a commitment to using 100 per cent clean or renewable energy by 2035.

The lower energy usage means LED street lights also save money, as street lighting is notoriously expensive - typically about 40 per cent of a city’s electricity costs. In San Diego, the savings turned out to be huge, “a quarter of a million dollars [per annum] just in energy savings, a 60 per cent reduction in energy use, and bulbs that went from one to three years of life to 10-13 years of life, which drastically reduces the maintenance costs as well,” says Graham.

“It’s a bit of a game changer in terms of the lighting itself,” adds Armin Mayer of GE’s Intelligent Cities programme. “I think people underestimate how disruptive this technology is, and for GE it has also brought significant changes to our business.”

While many cities are moving from traditional sodium or mercury vapour lamps to LED lighting because of the large energy savings, the other advantage of this new digital technology is making the street lights smart. LEDs are essentially electronic devices and when networked with sensing capabilities and cloud computing platforms, street lighting becomes tuneable.

San Diego’s existing lighting infrastructure “was essentially a dumb network,” says Graham, “but we now know for those 4,000 street lights what energy is being used, when they are on and off; we have dimming controls. We have now taken greater control of our street lighting network and really turned it into an intelligent network.”

Intelligent lampposts

The same level of control is being sought in Glasgow, which in 2013 won £24m of government funding to explore ways to create a smarter city. As well as a state-of-the-art city operations centre and data hub, the city chose three locations to demonstrate the benefits of smart street lighting, installing 180 intelligent lampposts in 2015.

Gary Walker, programme director of Future City Glasgow, explains dynamic smart lighting was used in one of the locations - a public walkway by the River Clyde: “We put in sensors that monitor either a walker or cyclist going by. The lights increase when someone is detected, until they go by, and then go back down by 20 per cent.”

In Glasgow, the ability to brighten and lower the lights is being used to create a safer public environment in another city centre test area, with noise sensors and video cameras linked to the operations centre. “If the light is operating at, say, 60 per cent capacity, but the noise goes above a certain level, that could indicate there may be some antisocial behaviour,” Walker says. “So the lights automatically go up in brightness and it gives us an opportunity to send an alert to the operation centre to say an incident has occurred.”

In San Diego, the ability to assist first responders is also being exploited. “You are talking about life-saving opportunities in the case of a fire or a medical emergencies,” says Graham, adding that it’s quite likely that in future their system could be used to manage traffic routes for emergency vehicles.

Lights can also be used to send community alerts. In Eindhoven, smart street lights have been programmed to flash red to warn residents of approaching storms and floods.

Another early adopter of intelligent street lighting is Amsterdam - also the city where street lighting was first installed, designed by Dutch inventor Jan van der Heyden in 1669. In February, the city launched a smart zone in Hoekenrodeplein in south-east Amsterdam, working with technology giant Cisco, Dutch telecoms company KPN and lighting expert Philips.

The city hopes to use lighting to engineer a safer public environment in this busy square, near the AJAX football stadium, various concert arenas and shopping areas. “Particular types of light do change the behaviour of people; we can almost call it the social science of light,” explains Bas Boorsma, Cisco’s Northern Europe leader for Internet of Everything. “If you have a rowdy group, you can actually change their behaviour by changing the lighting scheme. You can provide police with the opportunity to remotely hit a button and go to 100 per cent white light to respond to events.”

But lighting is just the tip of the iceberg for the street light - already a ubiquitous part of the urban infrastructure. “A light pole is becoming an icon of the street in the sense that it is actually becoming the vehicle for multiple sensors, cameras, Wi-Fi routers, digital signage and even electronic vehicle charging stations and yes, lights too,” says Boorsma. It is becoming part of the Internet of Things or what GE calls the ‘industrial Internet’, which is the key to making cities smart. This is where physical objects can collect and exchange data and be directly integrated with any other connected computer-based system. Essentially, each lamppost would have its own IP address. Cisco estimates the Internet of Things will consist of 50 billion devices connected to the Internet by 2020.

For cities this means that data collected via sensors and cameras on street lighting can become, as Graham puts it, “the intelligent heartbeat of the city”. So far, networked intelligent street lighting working with cloud-based analytical capabilities has been used to collect and process data on footfall, noise levels, humidity, air quality, traffic, seismic activity and even gunshots. GE recently joined with gunfire detection technology specialist ShotSpotter to integrate its real-time acoustic gunfire detection sensors and software into GE intelligent LED street lights.


Monitoring air quality is one function Glasgow has chosen to test in its intelligent street light demonstrator, because it allows flexibility. “These sensors connected through the street lights can be moved around within Wi-Fi zones,” says Walker, “so you can measure the air quality for a period of time, do some interventions and then go back and measure it again.”

Parking and traffic management is another area where intelligent street lighting can make cities smarter - and GE, like most of the companies involved, is developing solutions. This generally involves cameras attached to street lights that can detect parked vehicles. “If a car is parked illegally in a bus lane at rush hour, it can send an immediate alert to a tow truck to get that car out of the way to prevent congestion, whereas in the past you might need someone driving by to call the police or the traffic warden,” says Mayer.

He acknowledges that the idea of cameras on every street light can be a sensitive issue, but GE’s system does not collect the images themselves as they are translated into binary data, and analysed for trends before the information is purged from the light fixture. This allows the camera itself to be smart. “The amount of information you amass is huge, so you need software that says at the point of the street lights, it’s not a car, it’s a trash can blowing in the wind, so I’m not going to send that back to the server,” says Mayer. The ability to do this is what GE calls ‘edge analytics,’ and is key to how the Internet of Things will operate.

Parking has been a feature of the San Diego pilot, but according to Graham, “what we are now working on is how this can optimise parking in San Diego’s very dense urban downtown area. We want to be able to have an application for the public so that when you are heading downtown you can identify open spaces and parking opportunities rather than circling around”.

Engaging the community in an “open and transparent dialogue” has been important in San Diego, where Graham says feedback has been positive - the city even held a street party to seek public input on how the system could improve quality of life. And as the technology matures GE’s Mayer envisions an app store approach, “an open source approach, whereby developers can use the data in developing their own apps.”

Constant spying?

Making cities work better, through what was once just a mundane part of the street furniture, is exciting but, for some, also frightening. Cameras and sensors in every street light feels like big brother is really watching us.

Both GE and Cisco insist that generally personal data is not being collected or stored, nor are the systems used for monitoring individual activity. Mayer stresses that it is the city that owns all the data rather than the company. But Walker says privacy fears and general suspicion around sharing data among partnering organisations was one of the biggest problems for the Glasgow Future City demonstrator.

“People were saying, ‘Why do you want the data and what are you going to do with it?’” he says. “Starting the programme, it was really challenging to actually convince people that if you get this data, it’s going to be beneficial, and as we engaged with data owners, this process became more effective.”

The other big concern is with cybersecurity. Once a city’s infrastructure is networked, it becomes vulnerable to cyber-crime and even terrorism. So far, intelligent street lighting hasn’t been targeted, but in 2006 a traffic light control system in Los Angeles was hacked, causing days of gridlock. Cesar Cerrudo, security researcher and chief technology officer at security advisors IOActive, says cities are not taking the risks seriously enough: “Cities are adopting new technology without testing or making sure that the systems are secure. They chose something, install it and use it and that creates a lot of potential problems.”

He thinks it’s likely that the technology being deployed leaves data insufficiently encrypted, and says this is partly because some of those producing intelligent lighting systems are from the world of hardware, rather than software experts. Both GE and Cisco claim to take cybersecurity very seriously. Boorsma says all of Cisco’s systems have a default setting in case of any breach which will turn all outdoor lighting on.

Ninety per cent of the world’s estimated 600 million street lights still use traditional bulbs. But the switch to LEDs is happening quickly in the biggest cities, bringing along the rest of the smart city agenda with it. “San Diego right now is working on a blueprint for a $15-20m sensored street light deployment plan in its urban core,” says Graham, who expects the plan to cover at least a third of the city’s 40,000-plus fixtures. Glasgow, among other cities, is in the lead too - although the Glasgow project has only recently been completed, it already has a programme of LED light replacement for many of its 72,000 street lights and is using fixtures that can easily be adapted to be intelligent.

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