Smart lighting control brightens the future of Bluetooth illumination
Smart lighting is a key component of smart commercial buildings and the connected home. Based on LEDs—which use at least 75 percent less energy, and last up to 25 times longer than traditional incandescent lighting, according to the U.S. Department of Energy (DoE)—combined with Bluetooth LE SoCs like Nordic’s nRF52, nRF53, and the forthcoming nRF54 Series, smart lighting brings illumination into the modern age.
Not only can intelligent lighting minimize energy usage, by, for example, dimming when ambient light conditions brighten or switching off when people are not present, but it can also form a platform for other sensors such as proximity monitors and air quality sensors.
- Read more: Smart lights bring cuts to carbon emissions
The Bluetooth Special Interest Group (SIG) was quick to promote Bluetooth LE as a good connectivity option for smart lighting by highlighting the economies of scale that only the most widely deployed wireless radio standard in the world can provide. A further advantage is that Bluetooth LE is interoperability with almost every smartphone on the market, enabling the mobile to become a convenient interface for commissioning and controlling smart lighting.
But some tricky engineering challenges have threatened to stall smart lighting adoption. The good news is that first Bluetooth Mesh, and now the Bluetooth SIG’s recently announced Bluetooth NLC (Network Lighting Control) are providing solutions.
Adding mesh networking to Bluetooth
Bluetooth LE started life as a low power-consumption extension to Classic Bluetooth. In the early days it was designed for consumer type applications - for example wireless keyboards and mice or connecting peripherals such as fitness wearables to smartphones. Such applications require relatively simple peer-to-peer or star network topologies. In contrast, applications such as smart lighting—which features dense installations of wireless nodes—are best served by mesh networking.
In a mesh network, every node can talk to every other node rather than being restricted to communicating with just a central master node. That brings advantages such as built-in redundancy: if a node fails, messages can simply be rerouted through alternative paths.
- Read more: Mesh networks explained
To make Bluetooth LE more suitable for smart lighting, the Bluetooth SIG introduced Bluetooth Mesh. Making its debut in 2017, the tech offers features and options to create large-scale device networks. Without Bluetooth Mesh, individual lights are controlled from a central hub, restricting the position of each because it needs to remain in range of that hub. But with Bluetooth Mesh, a command rapidly propagates through the network with no position restriction on the lights - provided individual nodes are close enough together to communicate. It is also very easy to add or remove lights to or from the network.
- Read more: Bluetooth Mesh: A Glossary for Developers
- Learn more (webinar): Introduction to Bluetooth Mesh
Bringing greater interoperability to smart lighting
Bluetooth Mesh helped resolve some smart lighting engineering challenges but not all. The optional nature of Bluetooth Mesh’s features meant vendors had to choose a subset for their product segments. Challenges arose if vendors operating in the same product segments choose a set of options that didn’t work well with products from another vendor. For example, that made it frustrating for a consumer when features chosen for LED drivers from one maker were not compatible with features selected for light switches from another. Such problems undermined interoperability and consumer adoption.
Ensuring complete interoperability requires standardization across radio-, communication-, and device-layer of a wireless lighting control solution. Interoperability was ensured at the radio layer by using the Bluetooth LE protocol, and the communication layer through Bluetooth Mesh. But until now there was no solution for the device layer. To address this challenge, the Bluetooth SIG has developed a class of specifications called Bluetooth Mesh Device Profiles. These profiles define which options and features of the Bluetooth Mesh specification are mandatory for a certain kind of end-product – thus ensuring interoperability between different manufacturers’ versions of that type of device.
The first suite of mesh device profiles is collectively referred to as NLC profiles. According to the Bluetooth SIG, these profiles build on Bluetooth Mesh to form Bluetooth NLC, “the world’s first full-stack, multi-vendor interoperable wireless standard for wireless lighting control”.
Taking advantage of Bluetooth NLC with nRF Connect SDK
Nordic is the leading Bluetooth LE company in the world and is an enthusiastic supporter of Bluetooth Mesh and now Bluetooth NLC. That’s why we’ve immediately made it easier for developers to get started with the technology by including NLC profiles in the nRF Connect SDK.
The NLC profiles in the software development kit can be used to implement interoperable network controlled lighting setups, including ambient light and occupancy sensors, light controller, energy monitoring, scene selectors, and dimmer controls. Each of the profiles specifies a set of models and a set of performance parameters. The nRF Connect SDK provides a demonstration of how to implement each of these profiles as part of the Bluetooth samples contained in the kit.
- Learn more (technical documentation): Networked Lighting Control profiles
- Learn more (DevZone blog): Solving real-world challenges: The new features of Bluetooth mesh 1.1
- Learn more (webinar): Walkthrough Bluetooth Mesh 1.1 and Bluetooth Networked Lighting Control (NLC)
A bright future for wireless smart lighting
The shift from wired to wireless lighting control solutions is being driven by three main advantages: greater design flexibility, lower cost of deployment, and future extensibility.
Wireless systems allow for optimal placement of switches, lights, and other equipment, including places where it would be impractical for wired systems. Without the need for control wires, wireless lighting controls offer lower deployment costs. Decreased labor and material expense, minimum disruption during installation, and reduced maintenance costs also bring substantial savings. Finally, once deployed, wireless systems are easier to extend and it is simple to add advanced controls.
These advantages mean that wireless lighting is set to boom. The U.S. DoE, for example, forecasts that 28 percent of commercial lighting deployments will be wirelessly connected by 2035. With the interoperability Bluetooth NLC now brings to the device layer of wireless control systems, Bluetooth smart lighting will play a major role. The Bluetooth SIG says that Bluetooth NLC device shipments will grow at a CAGR of 115 percent between now and 2027. The future for smart lighting is very bright.
Learn more (webinar): Developing Bluetooth mesh products: Introduction