The proliferation of dimmable LED lighting and wireless connectivity has positioned connected lighting for strong growth. The biggest markets are expected to be linear, outdoor, and low- and high-bay applications, where high light output and long operating hours make networked control attractive. For the commercial sector, the U.S. Department of Energy recently estimated a 1 percent penetration in the total installed lighting base in 2015, then forecasted this will increase to 7–52 percent by 2025.
Why the big spread in the forecast? The disparity can be found in whether the industry continues along its current trajectory or takes steps to address significant adoption barriers. These steps include demonstrating and verifying energy savings, developing more user-friendly solutions, and ensuring interoperability among control devices.
Much of the conversation about interoperability focuses on protocols—rules that regulate communication between devices. For devices to communicate in a network, they must share a native protocol or use a gateway device or software function. The protocol may be an open standard (compatible devices from any manufacturer can connect), de facto open standard (manufacturer licenses technology to other companies, enabling interoperability) or proprietary (only manufacturer products connect).
A number of protocols are used in the connected wireless lighting market, including ZigBee, DALI’s wireless extension, Xbee, EnOcean, Bluetooth, the Synapse Network Appliance Protocol (SNAP) and many proprietary protocols. The wide range of protocols—not surprising as wireless building control is still a relatively young technology—can be challenging for electrical contractors.
In July 2017, Bluetooth released Bluetooth Mesh, enabling larger-scale, longer-range networks in nonresidential buildings. Bluetooth Mesh has broad potential commercial and industrial application, from building automation to the internet of things. So far, it has seen the quickest adoption in intelligent lighting, with products rolling out from companies like Eaton, Fulham, McWong and others.
Previously, Bluetooth was known for one-to-one pairing (e.g., audio streaming) and one-to-many broadcasting (e.g., beacons transmitting to multiple devices). Bluetooth Mesh marries Bluetooth’s open standard protocol with a popular topology called mesh, in which devices (nodes) in a network send messages to each other within radio range (many-to-many communication). The device may be a control device such as an occupancy sensor, or an intelligent luminaire. Messages could be commands such as on/off, data indicating luminaire status, etc. To cross larger distances, nodes use a managed flood architecture to relay them through the most efficient path in the network. If a device fails, the signal flow automatically reroutes through other devices, making the network “self-healing” for reliability.
The network can be operated by traditional control devices such as switches as well as current in-market smartphones and tablets. Mobile devices can add new nodes to the network and potentially provide user interfaces for monitoring and controlling nodes. Adding a centralized interface enables global control and programming, while data can be collected for analysis on a server or in the cloud.
“Bluetooth Mesh is the first wireless mesh networking solution designed from the start to meet the strict reliability, scalability and security requirements of commercial and industrial markets,” said Jim Katsandres, director of developer relations and evangelism at Bluetooth Special Interest Group. “Commercial lighting systems as well as industrial wireless sensor networks are great examples.”
He said Bluetooth Mesh is reliable because all nodes in the mesh network communicate directly with each other without hubs or routers. He said it also is scalable because it allows up to thousands of devices to communicate, and it is secure, incorporating industrial-grade security against attack.
“This degree of interoperability produces a ‘just works’ experience for users and generates confidence in products,” Katsandres said.
Bluetooth Mesh enables capabilities beyond mesh networking that developers can use to build more advanced solutions from an intelligent lighting platform. For example, the same Bluetooth chip in an intelligent luminaire could also serve as a beacon/receiver supporting location services, wayfinding, asset tracking and space optimization. Retail giant Target, for example, is currently upgrading its stores with intelligent luminaires that feature built-in Bluetooth beacons, which work with a Target app to guide shoppers to products while sending them relevant coupons and deals.
Interoperability is critical when evaluating connected lighting and networked lighting control. Bluetooth Mesh has made Bluetooth a more viable option among the protocols. Katsandres believes Bluetooth’s brand reputation, 20-year track record of enabling global interoperability and new mesh networking capabilities will drive the industry toward an open standard.
Learn more at bluetooth.com/mesh.