The World’s Best Thermostat Just Got Better
The genius of Nest’s smart heating and cooling system.
A year ago, I installed the Nest thermostat in my house and used it for a few weeks. I thought it was a breakthrough. The Nest, which was built by a start-up co-founded by Tony Fadell, the guy who designed the iPod, is not just the most beautiful thermostat in the world. A minimalist orb that resembles HAL, the Nest may well be one of the most beautiful objects you install in your home—it looks like something from the future, if the future were ruled by people with impeccable taste in Scandinavian furniture.
And the Nest didn’t stop at good looks. It was the world’s first “learning thermostat.” An ordinary thermostat asks you to program it to turn on and off at certain times and temperatures. Most people never do that; instead, they just set it at a constant temperature every season. Because a thermostat has always been a stupid device—it has no idea when you’re home or away, and no way of determining whether that temperature you set is really something you should aim for, considering the size of your home and your previous preferences—it obeys your edict until you remember to change it. Chances are you won’t remember, and you’ll end up wasting a lot of energy.
The Nest solves this problem through a battery of sensors and algorithms: It can figure out when you’re home and when you’re not, and based on your adjustments, it can build a model of temperatures that feel comfortable to you. It uses all this information to create a temperature schedule that’s personalized to your lifestyle, one that keeps you comfortable while saving energy. Considering that thermostats control half of a typical home’s energy bill, the Nest promised to be more than a great product—if thermostats like it took off, it could significantly cut down on our nation’s energy use.
But that was a year ago. Today Nest is announcing a new version of its thermostat. This upgraded version is slimmer than the old one, and the design of its front panel has been subtly streamlined. The new Nest—which sells for $249, the same price as the old one—also has two more internal connection slots that makes it compatible with more kinds of home heating and cooling systems; the company estimated that the first version worked with 75 percent of homes with low-voltage temperature systems, and the new version works with 95 percent of such homes. (Nest says its "best estimate" is that low-voltage systems account for more than 90 percent of American homes.)*
But the most noteworthy thing about the new Nest is that its improvements will benefit owners of the old Nest. This latest rollout includes a bunch of new algorithms that improve the efficiency and comfort it delivers, especially for homes with certain esoteric types of heating and cooling systems. But everyone who has the old Nest will get the same improvements. That’s because the Nest is connected to the Internet, and most of its functionality is enabled by its software. All the old Nests will get the new software, rendering them every bit as capable as the latest model. “There are a lot of homes in the U.S.,” says Matt Rogers, co-founder of Nest. “We don’t need people who have the first Nest to upgrade to the second one.”
We’ve seen this dynamic at play in the consumer electronics industry for many years—old phones and computers and video game systems keep getting new functionality through software updates. In a piece in 2008, I called this the “death of planned obsolescence,” and I hoped that this phenomenon would improve the longevity of our devices. What we’ve actually seen since then isn’t as hopeful. Because many of our latest gadgets are mobile devices whose inner hardware keeps getting outdated, their lifespans are limited: The first-generation iPad won’t run Apple’s latest version of iOS, for example, because it doesn’t have enough RAM.
But the Nest’s improvement suggests that the story will be very different for home devices. As thermostats, refrigerators, washing machines, dishwashers, sprinkler systems, and just about every other old-school system in your house gets hooked up to the Internet, you’ll notice something odd begin to happen: Rather than getting older and less capable every year, all those devices will keep getting better.
There are some technical explanations for this. “One of the reasons that Apple doesn’t do releases on old devices is that they’re bound by the CPU, the horsepower, or memory, or the battery—but we’re not constrained by that,” Rogers says. (Like many others at Nest, Rogers used to work at Apple.) The Nest has its own onboard processor, but if it ever gets outdated or overwhelmed, it can offload processing tasks to the cloud. The only real critical hardware inside a thermostat is “just a switch,” Rogers notes, and “we’re applying intelligence to how we use that switch.”
For instance, look at Auto Away, Nest’s system for turning off your heating or cooling when it notices you’re gone. In the old version, the algorithm was very rigid. “We’d always wait two hours without seeing people in the house and then turn it down, and if they came home we’d turn it back up,” Rogers says. After studying user data, though, Nest found some important nuances. “We found that morning patterns are very regular—when people leave in the morning, they’re gone,” Rogers says. So now, the Nest turns off your heating or cooling much sooner in the morning than it would at any other time of the day. Rogers points out that the morning is the coldest time of the day, and electricity is also expensive then, so turning on Auto Away sooner can make a big difference—now the Nest won’t waste energy heating your home when nobody’s there.
After talking to folks at Nest, I got the sense that this is just the tip of what’s possible. The more people use Nest, the more data Nests produce, and the better all Nests become—and on and on. “Eventually there may come a point where we say, ‘Wow, we’ve really solved all of the issues, we’ve saved as much energy as we possibly can,’ ” Rogers says. “But we’re not near that point yet.”
*Correction, Oct. 3, 2012: This article originally stated that the new Nest thermostat has one more internal connection slot than the old version. It has two new slots. In addition, the piece said the new Nest works in 95 percent of all homes. It works in 95 percent of homes with low-voltage temperature systems. (Return.)
Farhad Manjoo is Slate's technology columnist and the author of True Enough: Learning To Live in a Post-Fact Society. You can email him at firstname.lastname@example.org and follow him on Twitter.