Does the Nest save more than a programmable thermostat
I am rehashing this previous reader question because of a follow-up question brought to me on twitter. We have owned our Nest Thermostat for over a year now so I was able to go through our old bills and tell you exactly how much money the Nest thermostat has saved us.
- We had a programmable thermostat before purchasing The Nest so any additional savings is not due to switching to a programmable thermostat (it is due to switching to a learning one).
There is also the unfortunate fact that most people do not know how to use a programmable thermostat. Despite the fact that a programmable thermostat saves so much money, only about 30% of American households install a programmable thermostat. Of that 30%, only 47% of those are in the “program” mode (you can use a programmable thermostat like a regular one if you keep it out of the program mode).
This programmable thermostat study from 2010 goes through the problems with a programmable thermostat. A learning thermostat solves those problems. If you would rather use a programmable thermostat then this excellent post at House Logic: Programmable Thermostat goes through how you should program it to save you the most money.
About a Programmable Thermostat
A programmable thermostat will save you a lot of money on heating and cooling your home. When we moved into this home we wanted to install a better programmable thermostat and we decided to install Nest Thermostat. Our old programmable thermostat was a typical M-F/SS programmable thermostat (you can set a different schedule for those two options). Those do not work well for us because my husband works through the weekend and has two weekdays off. That means our schedule is not the same throughout the week.
The Nest is a learning thermostat. The Nest also has a few more features than a programmable thermostat does. If a programmable thermostat is programmed correctly then you will save approximately 20% of your heating and cooling costs (which generally make up about half of your bill). For the average American family in 2012, that means it will save about $175 each year. The Nest can (and will) save you even more money.
How does The Nest save More than a Programmable Thermostat
The short answer is YES, the Nest will save more money than a “regular” programmable thermostat and here is why:
- The Nest is a learning thermostat. That means it goes one step further than a typical programmable thermostat, which requires the user to set their own program. Recent research has shown that people with programmable thermostats often do not program them right or even at all. A learning thermostat does the work for you. It learns your schedule and the temperature you like and programs itself.
- The Nest uses Auto-Away to determine if you are home. When you leave your house it will automatically go to a “not home” setting. This will save you more if you have an irregular schedule because a simple program doesn't do anything in that case.
- The Nest has filter reminders so you know when to change your filter (this can save another 5% off your bill). Of course, you can change your filter with a programmable thermostat, you just have to remember when to do it.
- The Nest uses Airwave (one of my favorite features) to keep air circulating through your pipes, after your air conditioner has turned off, while the pipes are still cool. Each time our air circulates Airwave gives us an additional 5-6 minutes of cool air. This is my favorite feature simply because we have to use our Air Conditioner so much (we live in Arizona). It saves us quite a bit of air conditioner time.
- The Nest awards a Leaf when you save energy. While this doesn't save directly it does make it a competition of sorts to see how many you can get each month, challenging you to save even more money. If you sign up for email updates then you will get an email each month telling you how many leaves you earned, the average for your area, and the average for the country.
- The Nest is capable of learning a completely different schedule each day. Some programmable thermostats can do this too, but they tend to be the more expensive ones. Many of them allow you to set a schedule for the week and the weekend like our old programmable thermostat. This doesn't work for everybody (my son's weekend is Sat/Sun and my hubby's weekend is Tues/Wed).
- The Nest shows you how long it will take to get to your set temperature. Many people set a colder temperature thinking that will cool their home faster. The Nest shows you that is not the case so you don't end up paying for air you do not need.
- In some areas The Nest offers Rush Hour Rewards and Seasonal Savings. It communicates with your energy company and cools or heats your home during times that are cheaper for you.
There are a few other things I like about The Nest (the end of the month emails that analyze the energy we use and compares it to our neighbors, the fact that I can run my thermostat using my iPod so if I want it to turn on or off before we get home I can do that, and the graph that shows exactly when the air conditioner or heat kicks on).
How Much the Nest Saved us (vs. a Programmable Thermostat)
The Nest saves us more money than a regular programmable thermostat because of Airwave, the leaf, auto-away, and allowing for different schedules each day. If you have the same schedule every Monday-Friday and Saturday/Sunday, are very good about changing filters, and you program the best possible temperatures (and do not leave your house other than at the times that are programed) then The Nest will still save more due to Airwave and possibly due to earning a Leaf. If your schedule varies from day to day and week to week then The Nest will save you a lot more than a regular programmable thermostat.
We decided to install Nest Thermostat only 7 months after we moved in so I do not have a whole year of numbers to compare. The Nest will save on your heating and cooling costs so I used my electric numbers for the air conditioned months (our air conditioner is electric) and gas numbers for the heated months (our heat is gas).
Electric Nest Savings vs. a Programmable Thermostat
I had 3 months of electric bills before we switched to The Nest. We did make a few other changes that could have affected our bill. We put Gila Heat Control Window Film on all of our windows, we switched one bathroom and the kitchen to LED light bulbs, and we got rid of our dryer. All of these things could have also made (and probably did make) a significant difference on our electric bill.
We generally have the air conditioner running in May, June, July, August, September, October, and November. I only have stats for September, October, and November because we moved here at the end of August and we installed the Nest the following March.
- September. The year before we installed the Nest we used 1170 kwh's and the year after we used 917 (a 22% decrease). For us, that translates into $31.79 in savings.
- October. The year before we installed the Nest we used 1051 kwh's and the year after we used 661 (a 37% decrease). For us, that translates into $47.46 in savings.
- November. The year before we installed the Nest we used 655 kwh's and the year after we used 298 (a 55% decrease). For us, that translates into $43.45 in savings.
September was our lowest percentage savings, probably because we actually moved in a week or two after we turned everything on (so there were days with very little, if any, usage). We saw the most savings on the month of November, which could be attributed to the fact that the Nest seems to save us more on the “fringe” months because (in Arizona) airwave does not turn on near as often in July, August, and September as May, June, October, and November.
Our electric for the other 4 bills after the changes was 3264 kwh's. Using an average savings of 34.8% energy savings, we saved approximately 1136 kwh's ($138.25). Since I don't have electric bills for those four months prior to the changes, I have to use that approximation.
According to our bill, average temperatures were within a degree or two (either direction) from year to year.
Overall, we saved $260.95 on electric the first year. Remember, that is from the Nest, some new LED lights, the Gila window film, and getting rid of the dryer and electric water heater. Looking at the differences between our winter months, I think the Nest caused the majority of that savings (we saved 10-20% year to year on the winter electric usage) so the Nest probably accounts for half of the electric savings.
Gas Nest Savings vs. a Programmable Thermostat
I had 4 month of gas bills (while the heat was on) before we switched to the Nest. We made one other change that could have affected our bill (this time for the “worse”). We switched our water heater from electric to gas.
We generally have the heat running December, January, February, and March and I have a previous year bill for each of those (there will be no estimations for gas savings – all actual numbers).
- December. The year before we installed the Nest we used 8 therms of gas. The year after, we used 2 therms. For us, that translates into $6.03 in savings.
- January. The year before we installed the Nest we used 25 therms of gas. The year after, we used 13 therms. For us, that translates into $12.06 in savings.
- February. The year before we installed the Nest we used 17 therms of gas. The year after, we used 9 therms. For us, that translates into $8.04 in savings.
- March. The year before we installed the Nest we used 7 therms of gas. The year after, we used 4 therms. For us, that translates into $3.02 in savings.
According to our bill, the average monthly temperatures were comparable to the year before.
Overall, we saved $29.15 on gas the first year. Remember, we also switched our water heater from electric to gas, which would have made our gas usage higher.
A Learning or a Programmable Thermostat?
Both a learning and a programmable thermostat will save you money. The biggest difference is you do not have to think about it with a learning thermostat (compared to a programmable thermostat). If you follow the recommendations for your programmable thermostat you will still save a lot of money. We are pretty good about programming and we still were able to save money. I think that is mainly due to airwave, auto away, and not having to think about it.
Overall, the Nest is saving us approximately $160/year compared to our previous programmable thermostat. The other $130 in summer savings (and the 10-20% decrease on our winter electric bill) is due to our other upgrades. The thermostat costs $249 and I believe it is well worth the cost. If you have higher electric and gas bills you will probably save more. If you have lower electric and gas bills (or a lower electric and gas rate) then it will save you less. Even if you save half of that amount, the Nest will pay for itself by the fourth year of use.
Does anybody really want to spend their hard earned money on utility bills if they don't have to?
Where you can find the Nest (or a regular programmable thermostat)
You can purchase The Nest from Lowes, Amazon, or the Apple store. It is usually $249 although Amazon sometimes has the first generation available for less. There is a difference in the look of the first generation (it is thicker), but the software is the same and always will be. Once you install the Nest, it updates itself and it stores in the cloud so you will never need to upgrade.
There are a few other learning thermostat options since I first wrote this post. All of these are also great options.
- Honeywell Wi-Fi Smart Thermostat. This one retails for $249 as well, but you can find it on sale more often than the Nest.
- EcoBee. This one has a remote sensor. It also retails for $249.
- Honeywell Lyric Thermostat. This one judges when you are home based on your smartphone (if your smartphone is at home then so are you) rather than activity in the home. It retails for $279, but can sometimes be found on sale.