Your mileage may vary

Surveys say: It takes two years to recoup the cost of a Nest

If you’re thinking about paying $250 for the Nest thermostat, know that the resplendent regulator saves customers average of $131-$145 a year, according to a series of studies done by Nest and two other organizations. The studies were performed by Nest in 41 states with 1,500 users, by the Energy Trust of Oregon and by Vectren, a utility company based in Indiana covering 600 homes.

Each study was a bit different, but in general they found that customers saved 10 percent to 12 percent on their heating bills and 15 percent on their cooling bills. Previously Nest has gone with the standard guesstimate published by many thermostat providers and the EPA, which was that a properly programmed thermostat could save a consumer 20 percent on their energy bills.

As someone who works from home and thus doesn’t get to take advantage of the away setting, I can certainly say that installing a Nest (nor an Ecobee) has not let to huge savings, so I have long been suspicious of that 20 percent number. I also tend to keep my home “near boiling” in the summer according to the HVAC folks I speak to, which also means that my savings don’t come in anywhere near the higher range.

But it’s precisely those variables that make it hard to know how much you can expect to save from installing a pricey connected thermostat. In the case of Nest, the value comes from the learning algorithms and proximity sensors that figure out what temperature you like your home at and your schedule, which then start crafting the appropriate schedule that saves energy and keeps you comfortable.

So if you leave your home on a regular basis and your thermostat can take advantage of that to learn and adapt a schedule that cuts the heating or cooling during the day and at night, you may find yourself on the higher end of those savings — or even surpassing them. Or if you’re like me, you might find yourself not even hitting the low end of that average.

However, what’s nice is that as these connected thermostats become integrated with other devices in the home, it becomes about not just saving money on HVAC, but also about convenience from tying the messages from your thermostat to your other appliances. For example, because my Nest knows I’m away, it also can tell my lights. And if I’m away for multiple days, it tells my lights to randomly start going on and off to mimic me being home as a security feature.

If I had a connected appliance, it might also tell it when my utility was charging higher rates for energy, thus stopping me from doing laundry when it costs more. For many, those savings are a bit further in the future, but the nice thing about a connected device is that further savings may be just a software update away.

4 Responses to “Surveys say: It takes two years to recoup the cost of a Nest”

  1. Josh Schellenberg

    While the evidence is somewhat encouraging, the three studies cited in the white paper were not sufficient to conclusively prove that Nest thermostats save energy, based on the information that is available. The key shortcomings
    are:

    The three studies cited were not based on a randomized experiment

    The Energy Trust of Oregon study only included customers with heat pumps, and the regression specification used featured an alphabet soup of variables that seemingly were not subjected to sensitivity testing (the results of only one specification were shown)

    The study conducted independently by Nest included a highly self-selected group of customers that use Nest’s MyEnergy platform, and the methodological details and model validation were not provided

    The third-party evaluation for Vectren is summarized briefly in the white paper and is not available online (if you know where I can find this study, please let me know)

  2. Jas Paul Singh

    I like the convineance of controlling from my phone. The ease of programming day to day and in my case the extra sensors with ecobee3. I agree 20% number is likely not correct but a lot of people with $30 old fashioned thermostat likely don’t
    reduce even 2 degrees during sleep hours.

    I tried Nest but it went bad in a month and I found Ecobee3

  3. Does it take into account that a $30 programmable thermostat might be in place? Sometimes I question if it is worth it to spend $250 when a lot of people use the nest simply as a 7 days programmable thermostat