(iStock photo)

As Americans experience the start of winter -- in some cases, an extreme winter -- it's time to get out the sidewalk salt and clean the furnace. And, usually, to turn up the heat.

However, too few of us realize just how much energy and money we're wasting by using that terrifying and confusing device on the wall -- the thermostat -- in a just plain incorrect or flawed way.

Residential thermostats account for a staggering nine percent of all U.S. energy use. No wonder that according to the Department of Energy, leaving your thermostat set too high can lead to a much higher power bill -- and conversely, setting it back when you're away or asleep can lead to major savings. "You can save 5 percent to 15 percent a year on your heating bill -- a savings of as much as 1 percent for each degree if the setback period is eight hours long," reports the agency. 

Given figures like these, energy gurus have long offered some seemingly simple advice: Get yourself a programmable thermostat, which lets you enter multiple timed heat settings, and so ought to make lowering your thermostat at the right time a cinch. It sounds like an energy saving dream -- right?

Wrong. Much research suggests that many people just don't understand how to use their thermostats -- programmable or otherwise. Indeed, it has been estimated that only about 30 percent of homes actually have thermostats that can be programmed, despite the fact that this technology has been around for more than three decades. "Residential energy use (and savings) still depends largely on the settings of manual thermostats by the owners," notes a recent study.

And even among the programmable thermostat owners, there's reason to think that many or even most people aren't using them correctly. A 2003 study conducted by thermostat-maker Carrier found that just 47 percent of programmable thermostats were actually in the "program" mode -- in which, you know, they can actually be programmed.

Fifty three percent were in "hold" mode, which "functionally transforms the programmable thermostat into a manual thermostat." The situation is so bad that in 2009, the EPA's EnergyStar program suspended its program for programmable thermostats, noting that "while EPA recognizes the potential for programmable thermostats to save significant amounts of energy, there continue to be questions concerning the net energy savings and environmental benefits" that consumers were achieving with them.

So why can't we do better in a realm that promises vast energy savings if we get it right? The question is particularly pointed now as new smart thermostat technologies are abounding and utility companies seek to communicate with these advanced devices  to regulate energy use at times of peak demand.

The three problems with thermostats

There are three key overlapping problems here -- some of which involve thermostats and some of which involve humans.

1) There are problems with some thermostats themselves. One ergonomic study found that for the toughest-to-use programmable thermostat sampled, more than half of people could not figure out how to even put it in "heat" mode. Actually programming these devices was, obviously, a much higher bar -- and here, thermostat jargon posed a large problem. "In general, subjects were confused regarding the terms/functions temporary override, timed hold, permanent hold, permanent override, away and vacation," noted the study.

"I’ve been studying thermostats for 10 years, or more, and there are still thermostats that floor me," says Therese Peffer, one of the study authors and a researcher at the California Institute for Energy and Environment at the University of California Berkeley. "It still takes me time to figure out 'What the heck does that mean?'"

2) We didn't choose them. Many people don't go out and choose their thermostats because they actually like the product -- it's grandfathered into their lives when they move into an apartment, condo, or home where one already exists. They don't really know how to use it or program it, or even that they can. The manual may have been lost years ago. Thermostats may also be located in odd or incorrect places in the home -- in a dark hallway where you can't see the buttons or the temperature very well, or close to a window, where they're reading a cooler temperature than what actually exists throughout the home.

3) We're the problem, too. There are also numerous myths and misconceptions about how thermostats work and don't work, which may dissuade energy friendly operation. Take, for instance, the idea that if you set the thermostat to a lower temperature at night or when you're out, it takes more energy to warm the home back up again. Here's DOE's debunking of this falsehood:

In fact, as soon as your house drops below its normal temperature, it will lose energy to the surrounding environment more slowly. The lower the interior temperature, the slower the heat loss. So the longer your house remains at the lower temperature, the more energy you save, because your house has lost less energy than it would have at the higher temperature. 

So if you've ever been afraid to mess with your thermostat, or completely mystified by a bizarre thermostat in a hotel room, suffice it to say that you are definitely not alone.

The future may be better

So, what's being done to make the world's thermostats better? There's a clear trend toward linking up thermostats with smartphones and the Internet, and including features that move them beyond the realm of merely "programmable" into something "smart" and able to automatically adjust to or even learn from its user.

Thermostat maker Honeywell, for instance -- which built the famous thermostat known as "The Round" (we've all seen one) in the 1950s -- now offers Lyric, a smart thermostat that you can operate remotely from your phone. Lyric uses a technology called "geofencing" that "automatically sets back the thermostat when the home is empty and makes it comfortable when someone is home," says Brad Paine, general manager of the Lyric Platform at Honeywell Connected Home. You enable the feature in the Lyric app on your smartphone, and the thermostat then knows (from the smartphone's location) how close you are to home, and can switch your home temperature to a preferred setting when you are in close proximity. (Watch a video of how it works here.)

For thermostat researcher Peffer, remote programmability represents a pretty important breakthrough. "If people are going to go spend two weeks on a vacation and it’s in the dead of winter, they don’t want to come back to a house that’s 48 degrees," she says. "But if you can turn on your system when you’re at the airport on your phone, I think that’s a huge difference."

Nest Labs, maker of the  Nest thermostat, was bought by Google. (Photo illustration by George Frey/Getty Images)

And then there's Nest, another smart thermostat whose maker, Nest Labs, is now owned by Google. Nest actually "learns" your behavioral patterns -- and self-programs to save you energy.

“Most people don’t actually program their thermostat,” says Nest spokeswoman Zoz Cuccias, “so it puts more ask on the user.” So Nest in effect self-programs after learning your habits during the first week of use. Nest can also be controlled remotely, and it shows an encouraging little green leaf on the display when energy savings occur.

Granted, these tend to be the products bought by the wired and energy conscious. They're spreading, but there's some thermostat inertia in the population overall -- old thermostats that are inherited by new homebuyers may not be changed until they actually break down.

The EPA says it wants to get back in on the action, too. "EPA is working with industry to gather information about how smart thermostats can most effectively be used," said Jennifer Colaizzi, a press officer with the agency, who said an automatic thermostat can save $180 a year. "The first step is to establish a way to evaluate energy savings with data from the field."

For a lot of us, though, in order to save energy we may need to seize control of our climatic and energy fates. This winter, maybe a smart thermostat first requires a smart human.