Can a Smart Thermostat Really Save You Money?

Nest's Learning Thermostat

The idea of a smart thermostat sounds great. After all, what's not to love about a sleek-looking device that controls your home's heating and cooling systems automatically, promising to save you money and help the environment in the meantime?

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But whether these devices live up to that billing and to their steep price tags is up for debate. We did some digging to find out whether smart thermostats are worth your time and money.

What makes a thermostat "smart"?

Let's start at the beginning: What, exactly, is a smart thermostat and how does it differ from your run-of-the-mill temperature control devices? If you have a regular old thermostat – think round, with a dial, and probably splattered with paint from the last 3 times the room was renovated – you know you have to adjust the temperature manually any time you'd like a change. A programmable thermostat is a step up from there, allowing you to set temperatures that will be adjusted automatically throughout the day, based on the times you determine.

A programmable thermostat sounds pretty darn smart. And it is, if you take the time and effort to program it and update it regularly. Even so, that's just the tip of the iceberg when it comes to what smart thermostats can do. Today's models can be controlled remotely, through your smartphone or a web browser, and can adjust the temperature automatically when they detect that no one is in the house. They also can automatically adjust to ambient conditions such as humidity, and can show you how energy efficient – or inefficient – you are.

Ecobee3
The Ecobee3
credit: Ecobee

Smart thermostats may not be household names – yet – but you may have heard of a few of them. The Nest Learning Thermostat is arguably the best-known of the bunch, and its well-regarded, too. It requires very little input from the user, as it learns your schedules and movements throughout your house and adjusts the temperature accordingly. Similar is the Ecobee3, which includes a remote sensor that monitors temperature and movement in another area of the house, and Honeywell's Lyric Thermostat, which features a geofencing feature that will raise or lower the temperature of your house to your liking when you enter or exit a certain area.

Money matters

These devices sound cool, but they come with hefty price tags. The Nest and the Ecobee3 sell for about $250, while the Lyric (which is not as well-reviewed as its two rivals) can be found for under $200. They rarely go on sale – trust me, I've been waiting. So, at that price, they had better save you some serious cash off your heating and cooling bills, right?

Honeywell Lyric
Honeywell's Lyric Smart Thermostat
credit: Honeywell

Well, maybe. Nest performed its own study and found that users of its device save about 10-12 percent of their heat usage and 15 percent of their cooling usage. With those numbers, you could save the equivalent of the cost of the smart thermostat in about two years -- so not immediately, but faster than, say, a solar roof would pay for itself. If you have a programmable thermostat that you take the time to program (not a difficult or time-consuming task), you're likely to get very similar results – and Nest does acknowledge that the savings depends on how you already use your existing, non-smart thermostat.

That's not to say a smart thermostat isn't worth the investment. If you're the kind of person who can't or won't program your programmable thermostat, its savings potential is limited, and a smart thermostat may save you more money.

Likewise, if you lead a somewhat hectic or unpredictable life, a smart thermostat can adjust to your changing schedule, while a standard programmable thermostat is restricted by its own internal clock. And if you're likely to use the remote adjustment features, a smart thermostat could be a worthy investment.

Before investing in one of these devices, do your homework. Check out the product reviews, and visit the manufacturer's websites to confirm that your smart thermostat of choice will in fact work with your home's HVAC system.

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