By 2025, approximately 2.5 billion people will reside in cities, making up 66% of the world’s population; this has placed increased pressure services and infrastructure, putting a strain on available resources.
Furthermore, international organisations - such as the United Nations - representing the interests of a large number of countries across the world, are aiming to achieve net zero carbon emissions by 2050. This has provided further impetus for city planners to search for ways to improve operational efficiencies and reduce costs, while also enhancing the quality of life for its residents.
A regular feature within smart cities, yet one that remains an overlooked element in the growing IoT landscape, is smart street lighting. In cities which never sleep, smart lighting can form a comprehensive network that - with the right technology and interoperability - can act as a backbone for other large-scale IoT initiatives to be deployed without foundational costs or an extensive impact to the environment.
According to independent estimates, street lighting is currently responsible for up to 50% of public electricity consumption, so there is no doubt that the rising adoption of smart lighting has been driven by the global shift toward energy-efficient solutions. By 2030, the smart lighting market is expected to almost quadruple to $44 billion from approximates made in 2020. This is due to the technology’s ability to optimise and manage lighting for key city utilities such as streets, motorways, pedestrian walkways and public transport stations. Ultimately, it bolsters energy management, enabling cities to reduce power consumption while enhancing both aesthetics and public safety.
However, these lights are not merely an ‘on/off’ solution. Smart street lighting has emerged as a cornerstone of smart cities, providing a gateway to more innovative and broader IoT applications. This is not a theoretical claim either: research from Wi-SUN Alliance discovered that the adoption of street lighting IoT use cases expanded from 61% to 72% between 2017 and 2022.
Sparking IoT innovation
Over 326 million streetlights can be found worldwide, with the majority of these estimated to be deployed within large, populous cities such as London. Serving to demonstrate the growing demand for sustainability, one quarter of these streetlights have already been upgraded to energy-efficient LED technology, and more than 10 million smart streetlights are considered connected.
The move to LED lighting makes sense: it consumes up to 75% less energy than traditional lighting. With city planners and operators on the hunt for environmental and economic advantages, this technology has become pivotal to the implementation of smart lighting IoT initiatives.
If municipalities are to establish greener environments, then adopting the appropriate smart lighting technologies is crucial. Only then can they establish a ubiquitous, robust and scalable outdoor wireless communications network with street lighting as its foundation. This is achieved by connecting street lighting to a centralized management system, which ensures cities can access real-time information and facilitate data sharing among various municipal departments.
Through additional wireless connectivity and two-way communication, smart lighting can quickly become a foundational IoT canopy that offers many other solutions beyond illumination. Everything from the tracking of environmental data to the incorporation of smart sensors to manage traffic flow is possible.
Sensors play an important role in many of these applications. Once connected to streetlights, they can be used to provide the dynamic lighting capabilities determined by the movement of pedestrians or cyclists at night. Once smart lighting is deployed, various sensors can be deployed and connected to a city-wide network through the streetlight network. These sensors can serve a wide range of applications including public safety use cases such as monitoring areas for crime or to establish an early warning system for incidents like floods, landslides, hurricanes or droughts.
Wireless mesh networks
Given that it is critical for smart street lighting systems to function in real-time and adjust quickly to changing environmental conditions, scalable, secure, low-latency and long-range connectivity is required. Any interruption will lead to adverse outcomes. It is essential that these properties are also reflected in the communications network.
In a smart city, where numerous devices are deployed to monitor infrastructure, traffic and environmental conditions, the networks these are connected to must have consistently good coverage in what is a dense urban environment. Star networks encounter connectivity problems when used in narrow streets or when high rise, concrete and steel architecture is present.
Instead, wireless mesh networks are the ideal solution for smart cities. This is due to their ability to enhance connectivity, scalability, and resilience. The decentralized nature of mesh networks reduces reliance on centralized infrastructure as it can dynamically route data through multiple pathways, ensuring that communication remains uninterrupted even if some nodes fail or become overloaded. As cities evolve and the demand for connectivity grows, wireless mesh can be scalable. With its peer-to-peer infrastructure, newer nodes can be added without redeploying or rearchitecting the whole network.
For example, in a smart lighting mesh network, street light controllers interact with one another and with gateways that facilitate communication with the central management system. Adding more smart lighting devices to the network creates multiple communication paths, ensuring there will never be a single point of failure.
Interoperability: The underlining factor
Of course, to realize the potential of smarter, more sustainable lighting systems, interoperability and security should be a priority when choosing the right network topology. If cities are to grow sustainably and become truly smart, they require fast IoT implementation to rise to the modern demands of their residents.
Operators that have implemented proprietary networks for specific smart city applications often find themselves limited in terms of flexibility when it comes to upgrading their network technology or are looking to pursue other IoT initiatives. This is because proprietary networks rely on technology from a single vendor. This causes issues for network operators as it can introduce vendor lock in and halt the progress of network deployments if there is disruption to the supply chain.
A wireless mesh network based on an open, standards-based technology allows any vendor to pick it up, build a solution and deploy their technology with ease. Standards such as IEEE2857-2021 are spearheading a common framework for wireless technologies to create large-scale, outdoor, low-power, wide-area network such as sensor networks.
Technology that implements standards is often supported with rigorous certification programs, ensuring critical factors such as interoperability are considered. This level of confidence helps to provide cities with the flexibility to make modifications to their IoT networks and provide them with options to integrate new, third-party hardware and software from different suppliers with ease. As more planners realize the importance of standards and open technologies to the development of smart cities, then new initiatives and successes should just be over the horizon.
Author details: Phil Beecher, President and CEO of Wi-SUN Alliance
