The present system is like the lights will be switched on in the evening before the sun sets and they are switched off the next morning after there is sufficient light on the outside. But the actual timing for these lights to be switched on are when there is absolute darkness. With this, the power will be wasted up to some extent. In sunny and rainy days, ON and OFF time differ discernibly which is one of the significant hindrances of the present street lights systems. Also the manual operation of the lighting system is completely eliminated. The energy consumption in the entire world is increasing at the fastest rates due to population growth and economic development and the availability of energy sources remains woefully constrained.
Street lighting has been developed to undertake much more than simply lighting urban and suburban areas. It can now be integrated into a wider management platform for collecting and processing smart city sensors’ data related to transport, energy and city management, safety and security. Street lights play a critical role in making a city safe and convenient for its residents and transportation. According to the United Nations report, the number of urban dwellers in India will have increased by 416 million by 2050. The government is continuously focusing on road and infrastructure developments that indicate street lighting and energy consumption also. Imagine the energy consumption and challenges this can pose. However, with the host of several capabilities of smart street lights, these problems can be overcome.
With features, such as power scheduling, auto-dimming, sensor-based and connected lighting to IoT technology etc. The smart street lights have the potential of reducing energy costs by 50-70%. Which can solve the power supply problems and balance the electricity demand. Digitization is changing the way consumers, government and businesses interact with the physical world. The lighting industry is expected to be the next digital disruptor, owing to the increasing adoption of Internet of Things (IoT).
Smart Street Light Market in India
India is one of the biggest smart lighting markets in Asia Pacific. It is predicted that investments in smart lighting will double in the country and around 27.5 million street lamps will be replaced with LED lamps by 2022. One of the key reasons for replacing the traditional high-intensity discharge lamps (HID) is that they consume excessive energy and generate a lot of heat. Thus, with growing environmental awareness and to reduce carbon footprint, the government has started replacing the traditional street lights with smart street lights.
Currently $3.59 billion, the smart street light market is expected to reach 9 billion by 2024. Chicago is currently leading with a $160 million smart street light project that aims to replace 85% of the public lights in the city. Los Angeles has replaced 80% of its roadway lights with smart street lights seeing a 63% reduction in energy costs. Dallas, TX, is expecting to save approximately $90 million post replacement of conventional street lights.
Europe currently holds the largest share in the smart street light market at 34%, followed by North America. Let’s find out where India stands in smart street lighting infrastructure development.
Smart Street Lights in India
Smart lighting is an emerging technology that is replacing conventional lightings like halogens, CFLs, and incandescent bulbs with efficient LED lights and sensors for energy conservation. Smart lights have automated controls which make adjustments depending on various conditions like availability of daylight. The Indian government has started an initiative of developing 100 smart cities, and the lighting industry will be critical in ensuring sustainability. Its smart street light project UJALA aims at replacing conventional street lights in India with LEDs to reduce energy consumption and mitigate climate change.
The ROI from this huge step will certainly pave the way for the introduction of a more intelligent public lighting system.
IoT in Street Lighting
IoT-enabled smart lighting systems for smart cities are integrated systems that allow connecting street lights seamlessly through a wireless network. In an interconnected lighting system, street lights can be remotely controlled with sensors and smart controls – which is critical in the development of smart cities.
Benefits of Smart Street Lighting
Efficient Lighting – The first step of developing smart cities is replacing incandescent street bulbs with LEDs, the most efficient energy-saving street lights. This is because LEDs offer several benefits such as reduced CO2 emissions, lower energy consumption, lower bills, and longer life of street lights. And the best part is that the return on investment can be seen in just two years. Sensor-Based Lighting – The biggest advantage of sensor-based street lights is that the energy consumption is reduced dramatically since the sensors sense motion or traffic, and accordingly, turn the lights off or reduce their brightness. Moreover, sensor-based lighting can identify unusual movement, for example, an accident, and thereby increases security.Localised Control – Smart street lights, however, connected, can have localized control. This means that brightness can be reduced in some areas, or some areas may have only a few street lights on at one time, or lights can be turned on and off at different hours considering traffic and other factors. This again helps in cutting down the unnecessary power consumption. Seasonal Control – Seasonal control in smart lighting and design allows setting schedules and ‘trim times’. For example, in the summer season, street lights can be scheduled to turn on later and turn off earlier than in winter. Saving even a few minutes a day in a particular season can translate into a lot of money.Maintenance Control – Street lights get brighter after a good lens cleaning. Therefore, cities can save significantly if the intensity is automatically reduced after lens cleaning. Moreover, every time a light goes down or requires maintenance, the smart lighting system indicates the same, and maintenance can be done in time without having to hire engineers to run a check on all the lights.Lifetime Control – LEDs in smart lighting take longer to fade. Moreover, because of localized control, newer lights can be set at a lower intensity, increasing the age of the light. And doing this at scale can mean saving big bucks.
In developing smart cities, installing smart street lights is a very critical step that just cannot be overlooked.
Smart street lighting control systems
The idea of street lighting control appeared long ago, from the struggle of managing large numbers of lamps. A solution was needed so that the lamps could be clustered in smaller numbers and handled more efficiently in terms of powering on and off, power outages, maintenance etc. Thus, lighting panel control and monitoring units (power cabinets, feeder pillars) were invented and used to restructure public lighting. This allowed for each light segment to be manually powered on. Later, controllers were installed on these lighting control units. They took the place of human intervention, functioning as an automation for switching the light on and off.
Since then, street lighting needed to become more effective, less energy consuming, and less polluting. So, control systems have evolved to become ‘smart’ by allowing lamp control and data collection. This was made possible by allowing segment-level and lamp-level control via cabinet or luminaire controllers respectively.
Street lighting control levels
- A smart street lighting system controlled at segment-level comprises a cluster of up to 200 streetlight lamps that communicate to a power cabinet which allows automatic on/off control. The feeder pillar receives data from the lamps, manages and transmits the relevant data to a secure server, which stores and displays it on a dashboard.
- Individual lamp control is handled via luminaire controllers which have lamp-level functionality and intelligence, and allow for on/off/dimming control or adaptive lighting. Luminaire controllers can also provide electrical parameters feedback for every lamp, real time malfunction reporting and optional sensors to measure light, motion, temperature, humidity, noise, etc. In addition, lamp-level control keeps the lighting grid powered-up during the day, which allows the installation of other smart city applications: sensors, controllers, CCTV cameras or communication devices.
Lamp control standards, sensors and adaptive lighting
The main standards of lamp control are 0-10, DALI1, DALI2 (Digital Addressable Lighting Interface). The important thing is to make sure that the smart lighting controllers are compatible with the lamps’ control system.
Furthermore, some lighting controllers allow for further connectivity. Sensors for special functions can be added to the system, whether for deploying special lighting control characteristics or to mount additional, non-related sensors. Adaptive lighting is such an example. Adaptive lighting requires the ability to dim up the lamps in real time when presence (pedestrians or cars) is detected. This requires (besides controller’s technical ability) adding a motion sensor to the lighting pole, usually connected directly to the lighting controller.
Smart Street Lighting Communication Technology
The smart street lighting Communication networks can cover various ranges, depending on the distance at which poles can communicate with other poles and gateways.
Powerline Communication (PLC)
Powerline communication (PLC) works on long distances by sending a communication signal directly into the powerlines. Uninterrupted conductors establish a continuous communication, and the PLC signal doesn’t usually traverse any transformers or power conditioning devices.
When it comes to street lighting, it is generally the case that groups of streetlights share a common powerline. These street lights can either communicate with each other or communicate with gateways leading to supervisory control systems.
Gateways are tools which synchronize the communication between up to 200 lighting controllers and the lighting control software. Through wireless connection, an IoT gateway receives, filters and transitions the messages received from the controllers further to the management platform, where they can be analyzed.
Radio communication (RF)
In the street lighting field, Radio control (RF) manages to overcome most of the limitations of powerline communication. Although most smart street lighting systems function in a similar way, there are numerous different methods of exchanging data between connected smart streetlights and the CMS. These include cellular (2G, 3G, LTE, 5G, and NB-IoT), RF mesh, LoRa, Wi-Fi, and other medium- to long-range solutions.
A short-range network such as RF mesh has a maximum node-to-node distance of 200-300 meters and can comprise around 200 devices, and streetlights are about 50 meters apart. Short-range networks are suitable for urban areas where lamps are installed closer together and the message doesn’t need to travel for long distances. This type of network requires careful preliminary network planning, taking into account the density of nodes and the placement of gateways, which increases initial deployment costs. However, operating costs for an RF mesh network are much lower than for a cellular network because there are no data charges.
The ongoing urbanization is an issue that all cities need to deal with around the world. The smart city industry size is a $600 billion market, with 600 cities around the globe expected to generate 60% of the world’s GDP by 2025. With over 60% of the world’s population expected to live in cities by 2050, it is crucial that these cities are safe, suitable environments for their citizens. It is the end goal for smart cities to improve the safety and quality of the lives of citizens. The future is smart.