The lakeside city of Belo Horizonte in Brazil has followed an increasingly well-trodden path by seeking out Internet of Things (IoT) technology to solve problems. Like many cities before them, Belo Horizonte has chosen to begin their smart journey with street lighting. The network of lights that illuminate roads, sidewalks, and public spaces across all modern cities, provides a good starting point for smart city ambitions, reaching far beyond lighting to bring efficiency, safety, and digital intelligence to the urban landscape.

With a population of 2.5 million people, Belo Horizonte is the sixth-largest city in Brazil. It acts as the distribution and processing centre of a rich agricultural and mining region, as well as the nucleus of a burgeoning industrial complex focused on energy intensive manufacturing processes like steel, automobiles, textiles and mining products. Energy efficiency was, therefore, high on the agenda for the municipal government when streetlight upgrades reached the agenda.

The project began with research on all the public light points in 2017, plans were drawn up, and two years later, with the project now 90% complete, almost 182,000 streetlights have been upgraded with new LEDs. The installation has resulted in 50% electricity cost savings, the equivalent amount of electricity used by an estimated 34,000 Brazilian households in a year. Furthermore, material and maintenance costs have come down significantly. The deal struck between Belo Horizonte Iluminaçao Publica (BHIP) and Signify represents Brazil's first major public lighting public-private partnership.

Better street lighting provides better strength and distribution of light, which not only reduces poor-sight related accidents but also discourages criminal behavior and encourages social interaction. The energy savings, meanwhile, help the city achieve environmental targets, balance their power system, and demonstrates positive environmental values, in addition to actually helping reduce climate change. Smart street lighting is quickly becoming a no brainer for cities.

“In addition to the economic benefits, the installation of new lighting brings about a significant increase in the use of public spaces. Due to the different lighting from LEDs, public spaces are lit better, and for instance make it easier to recognize people’s faces at night, resulting in residents feeling safer to go for walks and have evening family picnics. Finally, the energy savings translate into helping the city reduce its carbon footprint,” reads a Signify press release.

Smart street lighting is becoming big business for many other leading firms in the space. Dan Evans, senior director of product management at Itron Inc., calls smart street lighting “the catalyst for the smart city network”. Evans worked with the city of Chicago, which is set to add traffic monitoring and management capabilities to the 270,000 smart streetlights it will have installed by the end of 2020.

In Copenhagen, where cyclist safety is a top priority, new cycle-centric traffic management capabilities will be deployed within its smart street lighting infrastructure. The city of Paris, which upgraded to smart streetlighting with Silver Spring Networks in 2015 is now looking to deploy sensors within its lighting poles to monitor moisture levels in soil for water conservation. There is more to street lighting networks than simple illumination, and its ubiquity across the city makes in the perfect platform for a range of smart systems.

“There's the fixture, sometimes referred to as the luminaire. Then, there's the control -- what we call a network lighting controller, or NLC. There's also the network. And, finally, there's the software for command and control and data collection,” Evans told IoT Agenda. “With multiple streetlights deployed with NLCs, you've created what we call a canopy network, which, as the name suggests, is an umbrella of coverage over your entire city or territory where the lights are. Now, any smart city application can be integrated with that network.”

Smart street lighting is acting as a “gateway technology” for young smart cities. Laying the foundation for easy installation of other smart systems, each enhancing the city and raising the bar for the more complex smart technology that will inevitably follow. Just like smart indoor lighting systems, the ubiquity of artificial light in almost all human spaces makes lighting networks one of the leading platforms for IoT deployment.