Introduction and Context
Perhaps hard to imagine today, but prior to 2011 few of us considered the thermostat beyond its most basic function: to maintain a steady, fixed temperature in our homes. Certain of us might have adjusted the temperature setting by hand prior to leaving for work or after returning home in order to save energy. But too often, we would forget to make that adjustment. Consequently, we failed to realize the potential of thermostats for energy savings.
Alternatively, we may have purchased a more advanced “digital” thermostat to program in sync with work schedules. But of course our lives don’t always conform to the same schedule. Therefore, energy savings remain limited, even with careful and complicated programming. For example, our patterns shift between weekdays, Saturdays, and Sundays. And some of us work weekends, nights, or odd shifts. Further, outside factors like Daylight Savings and power losses can wipe out our best efforts to achieve the “perfect” program. Certainly, more complex devices exist to overcome these problems. But often we revert either to manual overrides or to giving up on programming altogether. Particularly after that last long weekend, vacation, time change, or power loss!
Enter Nest Laboratories in the fall of 2011. Designed by former Apple engineers, the novel thermostat provided the look needed to alter our view of the hardware on our walls. However, beyond aesthetics, the thermostat was “smart” and could program itself based upon learning from our manual adjustments. Further, through motion sensing, it could also figure out when folks were home – and when they weren’t. Better yet, it connected to Wi-Fi, maintained network time, and gave us remote control. Even while on vacation!
Today, we increasingly view such smart thermostats as the emerging standard.
The greater connectivity and learning capabilities of smart thermostats allows for significant energy savings. Even without the full features of a smart thermostat, the US Department of Energy estimates we can save about 10% with manual setbacks or programmed temperature control. However, smart thermostats can save an additional 10% to 12% based upon research conducted by Nest.
Emporia Savings Calculations
In calculating savings, Emporia considers that 1) some users have yet to adopt smart thermostats, but can implement manual or programmed setbacks; 2) some users have installed smart thermostats; and 3) users engage at different levels that reasonably correlate to app use. Therefore, Emporia uses a range of 4% – 10% savings for users who report using manual or programmed setbacks.
For users with smart thermostats, an additional 5% – 12% energy savings is added, resulting in a net savings range of 9% to 22%. Note that the lower end of these ranges falls below that suggested in the Nest white paper (8% – 10% and 10% – 12%, respectively) and the higher end pushes marginally beyond Nest’s more favorable study savings of 20%. Doing so allows Emporia better to scale savings based upon engagement with the app. To wit, daily users receive credit for a full 22% savings. In contrast, a user who rarely opens the app receives only 9% savings. As motivation, Emporia has established a challenge goal to attain 50% energy savings using a suite of strategies.
As a further note, Emporia currently bases its savings only on electricity use. In the future, Emporia will consider other fuel sources including natural gas and heating oil.