After the LED Swap, the Lamp Still Does Not Know It Is Out
The change from older lamps to LED is largely done. What is left is control: dimming when the room is empty, a scene that follows the use of the space, a fault reported by the fitting itself, and an energy number you can attribute. In 2024 China's smart-lighting market was about RMB 47.9 billion, with shipments of about 39.57 million units. Commercial and industrial lighting is 57.2%; home, outdoor, and public lighting are 21.4%, 12.2%, and 9.3%. Streetlights, parks, buildings, and homes are where the connected share is still rising.
What Is Shipping
The market moved from about RMB 39.8 billion in 2022 to about RMB 47.9 billion in 2024, roughly 10% a year. Ceiling lights are 28.8% of shipments, switches 19.3%, downlights and spotlights 16.5%, bulbs 14.8%. Specialist lighting makers hold about 38.9%. Technology firms and whole-home brands are moving in. DALI, Zigbee, Bluetooth Mesh, and power-line carrier sit side by side. A cloud platform is the place they are supposed to meet.
Policy and the Bus
The 14th Five-Year Urban Lighting Development Plan pushes smart streetlights and energy retrofits. The General Code for Building Energy Efficiency and Renewable Energy Utilization caps lighting energy in public buildings. DALI-2 is the addressable interface most new jobs specify. Streetlights and park lighting in China more often use NB-IoT or 4G, because the run is outdoors, wide, and the fitting should not draw much. CJJ 45-2015, Standard for Lighting Design of Urban Roads, sets main-road illuminance at 15–30 lux. One DALI bus addresses 64 devices and dims from 0.1% to 100%.
What the Old Circuit Cannot Do
An outage found by a phone call. A city has too many lamps for a short inspection round. A dark lamp or a flicker is usually reported by a resident. A single-lamp controller, on power-line carrier or a wireless link, reports each fitting. The crew goes to that pole, not to the whole street. Maintenance throughput rises several times over.
Full brightness on a clock. Public lighting often runs a fixed schedule at full output, ignoring footfall, weather, and season. A light sensor, a presence sensor, and an astronomical clock dim an empty hour, bring the lamps on early in rain, and shorten summer nights. Combined savings are often 20–40%.
Lighting, cooling, and security that do not share a room. In a building or a park they are separate systems. One platform can turn off the lights and the air conditioner in an empty meeting room, and dim a corridor to the people actually in it.
Where the Controller Sits
The streetlight. The single-lamp controller reports voltage, current, power, and faults, and accepts a remote on, off, dim, or schedule. The pole may also carry environment sensors, Wi-Fi, a camera, or an EV charger. That is a smart pole, and one gateway is how those services share a backhaul.
The building and the park. Offices, parking, and landscape lighting take a strategy by zone, by hour, and by scene. Presence and daylight hold the illuminance the standard asks for without leaving an empty bay at 100%.
Home and retail. Lamps and switches mesh over Zigbee or Bluetooth. The gateway reaches the cloud on Wi-Fi or 4G. An app or a voice command changes level, color, and scene. A shop can switch the look for opening hours or for an event in one step.
Who Builds It, and Two Jobs
Upstream is the LED chip, the driver, and the sensor. Midstream is the single-lamp controller, the gateway, and the cloud. Downstream is the city, the park, and the building owner. One prefecture-level city put NB-IoT controllers on 28,000 lamps. Faults that took about 24 hours to notice are seen in about 15 minutes. Maintenance cost fell about 40%, and energy about 28%. A park running DALI with occupancy sensing cut office lighting energy by about 35%.
Terms on the Same Drawing
DALI is the Digital Addressable Lighting Interface, the control bus lighting jobs actually specify. Single-lamp control is monitoring and commanding each streetlight on its own. A smart pole carries lighting plus communications, cameras, and environment sensors on one column. Lighting on demand is dimming to the use, rather than leaving the circuit at full output because the schedule says so.
Where It Is Heading
The smart pole is becoming a piece of city infrastructure: a 5G small cell, a vehicle-to-road radio, not only a lamp. LiFi, visible-light communication, is the experiment that tries to make the fitting a link as well as a light. Dual-carbon targets are pushing both the energy cut and photovoltaic-plus-lighting packages. SimtoLink supplies 4G and NB-IoT for the streetlight controller, the gateway, and the sensor, so a lamp at the end of a road reports the outage itself.
Summary
Single-lamp control, dimming to the room, a fault that does not wait for a complaint, and lighting that can share a scene with the air conditioner: that is the job after the LED retrofit. SimtoLink's part is the cellular link on the controller and the gateway, including a pole the maintenance crew will not drive past until something tells them to.