The Department of Energy and utilities such as PG&E and Consolidated Edison recommended turning the thermostat to 68 degrees Fahrenheit during the winter. So I programmed the Nest for 68 during the day.
When the $370 bill arrived a month later, I realized the rule of thumb was terrible for my two-bedroom house, which was built in the 1960s with insulation as an afterthought. Once the house reached 68 degrees, it couldn’t hold that temperature for long, so the oven turned on again about 20 minutes later.
This all means that saving energy with technology requires some independent thinking. While it might make sense to leave the thermostat at 68 all day for small apartments in well-insulated buildings, this is general advice that many homes probably won’t benefit from, says Ben Brown, Google’s product manager for the Nest thermostat.
Instead, ask yourself some questions. What is the size of your home? What do you know about the insulation? How long does it take to warm up a few degrees? And most importantly, what temperature would you and your family feel comfortable at?
In November I decided to try and make the Nest work better in my house this winter. After tinkering with Nest’s settings and studying my energy costs every day for a month, I came to the conclusion that this was the best schedule for my home:
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6:30 a.m.: Raise the temperature to 66, for when it’s time to get out of bed.
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8 hours: Set the temperature to 60 so that the temperature drops steadily during the day. This made the house a bit cold, but bearable to wear a sweater.
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8pm: Raise the temp to 66, for when it gets cold at night (and after peak PG&E).
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23:00: Set the temperature to 57, before going to sleep.
During this experiment, the Nest thermostat also gave me a warning that my oven was turning on and off every few minutes, meaning something was wrong. I hired an HVAC professional who diagnosed and fixed the problem: The gas pressure was too high, causing the oven to overheat and shut down automatically.
This solution, combined with the programmed heating schedule, resulted in a significant reduction in my bills.
2. “Vampire energy” is an exaggerated problem.
In December, after finishing my experiment with gas, I turned my attention to electricity. The results were less remarkable.
