What is inside Smart Lighting Systems?

Notwithstanding fears of security holes in IoT, the global Smart Lighting market is growing at 22% CAGR, and is forecast to reach $20-$47B by 2020, depending on whose report you read. Even if it’s only a fraction of that, it’s still a huge market.

Smart lightbulbs seem to be a hit in Smart Homes with some models featuring wireless speakers, ambient light sensors, motion detectors and/or HD cameras, which bring additional value as well as convenient, discreet deployment. But the commercial sector stands to gain most, with huge savings in energy costs and a range of new applications.

Since Smart lightbulbs first hit the market around 2010, they have evolved quite a bit, from independently controlled Bluetooth, Wi-Fi and ZigBee enabled LED bulbs and light switches, to complete industrial-grade lighting control systems based on Powerline, Ethernet, Wi-Fi and other wireless technologies, suitable for commercial applications both indoor and outdoor.

So what’s in them and how do different solutions work?

Smart Bulb vs Smart Lighting System ROI

Putting the smarts in the bulb or the switch has obvious benefits in reducing or eliminating changes to the existing infrastructure. That's a great proposition for home owners – but at premium cost. A typical home might have 20 or more light fixtures. At ~ $50 a pop you’re looking at a $1000 bill for some cool lighting and marginal energy savings - unlikely to yield ROI in less than three or four years, assuming you already switched from incandescent bulbs. From the blogosphere, it is clear the majority of early adopters are only swapping out bulbs and switches selectively – not retrofitting entire homes.

In commercial / business settings, the motivation for smart lighting used to be solely on energy savings, given that lighting accounts for about 40% of the total energy costs in a commercial building, and now there is growing attention to the potential of new lighting applications.

Commercial buildings may have a few hundred fixtures per floor, so $50 per fixture is cost prohibitive. Smart lighting systems put the smarts in the network which enables centralized management and reduces the cost of bulbs. Vendors are touting 40-70% savings in lighting energy costs with as little as a one year payback.

Enabling New Applications

In smart city deployments, in addition to energy savings and reduced maintenance, city planners are also hoping to enable a variety of new operational, public safety and public health applications. As a result, there is considerable interest in adding a variety of related sensors to lamp fixtures to monitor daylight, occupancy (people or vehicles), sound, temperature, air quality, radiation, humidity and more, depending on the use case.

For example, as a public safety measure, using sound detection and recording, it is possible to triangulate the location of a gunshot, and alert the police with an exact GPS location and a recording of the sounds. Or using a combination of other sensors, cities could illuminate streets during the daytime, in stormy conditions, or illuminate differently for special events.

What is inside the Smart Bulb?

Components inside the bulb include:

Power management: Step down from 120/240V to 12, 6 or 3v to drive LEDs and sensors and other output devices such as speakers.

Microprocessor: Running a stripped down Linux or other RTOS with security components, and running drivers and agents to acquire data from sensors, and send it to a smartphone, hub or the cloud over a wireless connection.

Wireless radio(s): One or more of the following Wi-Fi, BLE, ZigBee and others in some cases. Support for more than one radio is becoming more common as chip functions consolidate.

Environment Sensors: Any of the following might be included motion, temperature, humidity, ambient light, sound. Motion and sound could be used to detect intruders for home security applications, while temp and humidity sensors might be used as inputs to a Smart HVAC system.

Depending on the wireless technologies used in the light bulb or light switch some will require a hub or a gateway, in order to connect the bulb or switch to a home Wi-Fi network, so that the fixtures can be controlled remotely via Cloud applications. Vendors in this space are trying to make their hubs as open as possible, hoping to get a foothold for other smart home applications in future. There is some degree of interoperability between products from Wink, Phillips and several others. Without connectivity to the home network, the fixtures may be controlled directly using Bluetooth from a smartphone or tablet, but only with a physical presence.

What is inside a Smart Lighting System?

This depends somewhat whether it is deployed indoor or outdoor.

LEDs are low-voltage DC devices. To work with traditional AC power sources, LED drivers must use an AC-to-DC converter to step-down the AC mains power to a lower DC voltage. This is power-inefficient and it adds cost to each bulb. So smart building lighting systems are shifting to Ethernet based cabling with PoE to power the bulb and the electronics in the light fixture. This approach is more power efficient, and addresses networking and power in one shot, without burdening the bulb cost. It also maximizes flexibility to use low cost LED bulbs or semi-smart bulbs from different sources.

Indoor deployments: PoE based LED lighting is now mainstream and is an obvious choice for deployment indoors in new commercial developments or major building retrofits. Because of the LAN / WLAN infrastructure expected to be present in any modern facility, other low-power building automation solutions (Security systems, Surveillance, HVAC etc.) have already followed this PoE path.

Many vendors in this space are looking beyond mere lighting control, by evolving their cloud or premises-based control systems to be more like IoT platforms – with APIs to enable other vendor’s building automation devices to be unified, or enable partners and users to develop custom applications, on top of their management framework.

Combining sensors and smart lighting is not the only direction we are seeing. There are also new applications emerging which combine smart lighting and wireless communications, for example incorporating a Wi-Fi Access Point or Bluetooth beacon in lighting fixtures in retail-establishments can provide shopper assistance and push marketing, location tracking and customer analytics.

Outdoor deployments: Cities waste a fortune over-lighting unused streets and public buildings. They need a wide array of different solutions, and because of the distances involved, most of them will use one of several narrow-band wireless technologies (e.g. 6LoWPAN, LoRa, 802.11ah, Z-Wave, ZigBee as well as 2G/3G/4G) that offer greater range than Wi-Fi or Bluetooth.

Meanwhile, municipalities also face constant pressure from carriers to expand the mobile broadband infrastructure for new cell towers and micro-cell sites. Ericsson and Phillips have come up with a way to densify mobile networks without cluttering the city. Their This Zero Site solution uses a multiservice smart lamp pole designed to house small cells, Wi-Fi hotspots and other network gear, in which the space can be rented to MNOs

Municipalities and Utilities will use a combination of solutions to address different communications and lighting needs. For example the utility company Georgia Power which has installed 500,000 LED fixtures over the last four years uses a mix of star- and mesh-topology wireless networks supporting different standards.

Li-Fi and Smart Lighting Alliance

Another spin on this market is a new technological advance called Li-Fi. This is using the visible light spectrum to transmit data in short range just like Wi-Fi does. It is achieved by turning an LED on and off extremely rapidly (much faster than a human eye can detect). Researchers have accomplished data rates from 70 Mbps for light reflected off a wall up to a blazing 10 Gbps (demonstrated in 2014 by Sisoft) with direct line of sight. Since light can’t go through walls like radio waves, Li-Fi has some limitations, but it offers huge potential as a complimentary technology to Wi-Fi and cellular and could potentially alleviate the competition for Wi-Fi since it is using completely different spectrum. Researchers say they can transmit data even with very low levels of light emissions, dismissing the obvious misconception that the lights need to be blazing for this to work.

Outdoors this could be a compelling solution for Cites, which could enable them to autonomously offer city-wide Internet access through the lighting infrastructure, while remaining immune to interference from public Wi-Fi hotspots and LTE-U and its variants. Li-Fi does not suffer the constrained spectrum of Wi-Fi which is already becoming congested even in the 5GHz band, because the visible light spectrum is 10,000 times larger than the entire RF spectrum, of which Wi-Fi occupies only a tiny fraction.

The Smart Lighting alliance is on a mission to make this happen, and has committed to developing the necessary components to Li-Fi enable Smartphones, Tablets and other mobile devices. If Li-Fi takes off in Smart Cities and the highways, it seems likely this would apply to the Connected Car market as well.

Where does embedUR come into this?

As experts in embedded software engineering and Wi-Fi and IoT enablement, we are helping clients to design their solutions for easy future integration of related sensors and wireless technologies. So much in the IoT is new territory, it is uncertain what new application is around the corner. So device vendors and service providers must be cautious to keep their solutions as open and flexible as possible. We’re helping them do that.