The extensive application of a new generation of information and communication technology, such as Internet of Things (IOT) and cloud computing, combined with the trend of smart city energy saving and environmental sustainability has led to the development of smart streetlights. Sensors are being installed on urban streetlights to turn conventional streetlights into smart streetlights, which when linked to a network are capable of collecting and analyzing the data from the surrounding environment and traffic information. According to Northeast Group, a research institute, the market scale of the global streetlight market was about 315 million streetlights in 2016, and this will grow to 359 million streetlights by 2026, wherein the market scale of global LED streetlights and smart streetlights will be up to $69.5 billion. Based on a market survey conducted by Philips, only 1% of global streetlight systems installed have networking capabilities. However, the average compound annual growth rate is 16%.

Solutions to the problems of IoT deployment and power supply

Smart cities make full use of technologies, such as sensing, mobile networks and cloud computing, to integrate and analyze key urban information to meet the demands of traffic management, public safety and services for industry and business sectors. To achieve these goals, IoT terminal equipment for information collection and processing is required, and streetlights can solve the two biggest issues for IoT equipment (location and power supply) through their two major advantages: deployment and power system.

However, the applications of smart streetlights in outdoor lighting are extensive and numerous, and selecting an appropriate communications technology to network sensors is another issue. Short-range transmission systems, such as ZigBee, are limited by low coverage, a large number of gateways required and high equipment maintenance cost. Traditional 2G/3G/4G networks for IoT M2M transmission offer a broader coverage, but cannot satisfy the IoT equipment’s requirement for low power consumption and low costs. As a result, a low-power, wide-area wireless technology (LPWA) has emerged. LPWA has three major features: long-distance communication, low bit rate data transmission and low power consumption, which make it suitable for IOT applications requiring long-distance transmission, transmitting small amounts of communication data and using battery-powered sensors.

LPWA has already been applied to smart streetlights. Telensa has established PLANet, an outdoor single light control system network that covers 130,000 smart streetlights in Essex, UK. Because PLANet uses LPWA for data transmission, and flexibly adjusts lighting based on several factors, it can save energy and electricity. In addition, Telensa has also deployed sensors on the streetlights to sense vehicle presence. Divers can use this service to know if there are parking spaces nearby, so that traffic lights can facilitate traffic, save energy and even assist the police in handling cases. LPWA is expected to be gradually adopted for smart streetlighting.

Another example is Cisco’s discussion of a 10-year, $15 million smart city infrastructure project with Kansas City, Missouri, U.S.A. in 2014. Phase I of the project was officially started in 2016. Cisco installed 125 smart streetlights in the city center, which can offer an 80% energy saving compared with traditional streetlights. Kansas City can use the smart city infrastructure, such as the smart streetlights to increase revenue by, for example, the installation of smart sensors near parking areas, so that the smart streetlights can guide drivers to vacant spaces, automatic time billing can be facilitated by the sensors and payment of parking fees can be done online through an app.

For cities, there are obvious advantages for building smart streetlights, including extensive coverage, energy savings, remote monitoring of the roads, monitoring of the urban environment and applications for transportation and safety. However, network security is a problem to be considered when more and more cities are storing data on the cloud. Moreover, the privacy of citizens may become another issue as the number and type of sensors increases, such as if video surveillance and sound sensors are installed on smart streetlights. Therefore, manufacturers must pay attention to possible privacy issues at the design stage.

Furthermore, the source of funding, the structure of ownership and whether the management of infrastructure is outsourced should be considered when converting to smart streetlights. Sensors or additional functions cannot be installed on the streetlights without due consideration or planning, for example, the use of streetlights as electric car charging stations, free wireless hotspots and video surveillance applications. Smart cities in different countries and scenarios have different needs. When building smart streetlights, each city must be assessed on a case by case basis to solve the practical problems of that particular city and so maximize the benefits of the smart streetlights.

From product development of software and hardware integration to services

IoT devices tend to have a long life cycle. Once purchased and installed, they will be used for a long time, and will not be retired or replaced soon. The IoT value will be enhanced by providing customized and innovative services for more value-added functions and applications. One of the topics to be considered by the smart streetlights industry is how to gain profit from software and services while still ensuring a share of hardware sales revenue.
For example, GE has switched from hardware sales to a service-oriented business model. Smart streetlights are not only profitable from an equipment perspective, but also from the various data collected by the streetlights. If a local government wants to use the data to develop urban solutions, it has to pay GE data processing fees. Moreover, GE offers developers free use of the streetlight-related data for 60 days for the R&D of smart city applications. If the developers wish to continue to use the data, they will be charged. This is GE’s strategy to attract various parties to participate in development and rapidly expand the user base and number of urban applications.

Therefore, the smart streetlights industry should consider switching from product development through integration of hardware and software to a service-oriented business model, and form an ecosystem with the government, research institutes and start-ups to use smart streetlights to support various smart services through data collection, analysis and feedback.