Neil Joseph was sitting at his desk in the Tesla Motors's Silicon Valley office a little over a year ago, when something started to bother him. The wide-open office was flooded with sunlight, yet the overhead lights were running at full blast. “Why aren’t these lights adjusting themselves, the way our phones and TVs do?” he thought.
After searching high and low for a bulb with that kind of smarts, Joseph came up empty. Connected LEDs like the Philips Hue rely on a user to schedule their on and off periods, and automated systems only exist on the commercial scale and cost tens of thousands of dollars.
At the TechCrunch Disrupt conference in San Francisco, Joseph unveiled Alba, the first bulb from Stack, the company he left Tesla to found last October. Alba, he says, is the first “responsive” light; it uses embedded sensors to adjust itself based on current lighting conditions and whether or not people are in the room.
The key difference between Alba and other smart bulbs is how easy it is to set up and use. Users screw the LEDs into their light sockets (for now the bulb fits into standard recessed lights, but other styles, including the ubiquitous Edison-style are coming) and plug the Stack hub, a small box continaining a wireless radio that connects on the popular ZigBee home-automation standard, into their wireless router. From there, the bulbs and hub use their collective smarts to start automating themselves.
Each LED contains a circuit board with a microprocessor, wireless radio, motion sensor and ambient light sensor. The motion sensor will make sure the lights are on when someone is in the room, while the ambient light sensor dims or brightens the bulb based on the current lighting conditions in the space.
The Alba also knows the time of day and adjusts the temperature of the light to sync with the body’s natural circadian rhythm. In the morning, the light will take on a blueish hue, which helps your body wake up; in the evening, it will be warmer—red or yellow—to soothe and relax you. The scheme is based on years of research at Thomas Jefferson University and various lighting companies.
Joseph believes Stack’s presets will work for 98 percent of users 98 percent of the time. And, because the bulbs won’t burn when they’re not needed, Joseph estimates that his system will cut lighting costs by up to 80 percent compared to other LEDs.
If the presets aren’t a perfect match, the Stack’s artificial intelligence will learn an individual’s patterns and adjust the bulb's schedules accordingly over time. “Let’s say you set up the system and have it for a couple weeks,” Joseph explains, “but you continue to use the light switch to turn it on and off; it will learn ‘this is when these sets of lights are usually off or on,’ and it would keep that pattern.”
But homeowners can always use the Stack app to override the automation—even enhance it. Through the app, they can set up groupings of lights for specific rooms, create schedules and select pre-set lighting themes. For example, an early riser could set his wake-up time for 6 a.m. and bedtime for 9 p.m., and the color temperature schedule will adjust itself accordingly. Users can also override the bulb’s prescribed lighting schemes. Say, for instance, it’s nighttime so the bulbs want to be bright, but the kids want to watch a movie in near darkness; Mom or Dad can select a movie-viewing theme or dim the lights manually.
Taken on their own, the Alba’s features aren’t entirely new in the lighting world. Savvy homeowners have been able to set lighting schedules and adjust light temperatures since the Hue and similar bulbs, including a set from Greenwave Systems and the Kickstarter-backed LIFX. Intrepid users can also hack the the Hue to work somewhat autonomously. At the same time, the Lighting Science Group has perfected its "Good Night" and "Awake and Alert" bulbs in collaboration with NASA.
But, Joseph explains, baking all those ingredients into one self-adjusting bulb was something of a challenge. “We engineered [all the electronics] on our own,” he says. “Making the sensors work when they’re right next to the light source itself proved to be especially challenging. You’re trying to measure ambient light 10 or 15 feet away, but at the same time you’re right next to a really bright light source.” Joseph likens the final solution to a pair of noise-canceling headphones; the bulb’s processor knows how much light it’s making on its own and cancels that brightness out of the sensor’s readings.
Thanks to their embedded sensors, Joseph hopes that Stack bulbs could one day serve as the central nervous system in a connected home. “Lightbulbs are the most common electric device in a building,” Joseph says. “With each bulb having a sensor in it, it’s able to understand what’s going on in a certain place.” For example, if the family is clustered in the kitchen, not only could the bulbs be able to tell other lights in the house to turn off, but they could also alert the thermostat to adjust the temperature in that “zone” accordingly.
Stack will launch the Alba in the first quarter of 2015. A starter kit of two bulbs and a wireless hub will run $150, and additional bulbs will cost $60 each.