With summer approaching and energy bills skyrocketing, many Americans face some difficult decisions as to how to use their thermostat and air conditioners. Now the U.S. Department of Energy has stepped in with some guidance that may sound a touch counterintuitive for those trying to beat the heat while keeping their costs as low as possible.
The official guidance to stay cool but to minimize costs is to set your home’s temperature to a higher figure when nobody is home, and then to keep it as high as comfortably possible when occupied.
What does that look like in practice? Well, according to the government affiliated Energy Star program (opens in new tab), you should keep your home at 78 degrees while at home, 82 degrees when asleep and 85 degrees when away.
That sounds odd: surely setting your thermostat to a lower temperature will cool your home faster? Unfortunately, that’s not the case: an air conditioner can only really make your home 15 to 20 degrees cooler than the temperature outside, and if you drop it lower than that, you’re just burning money with massively diminishing returns.
On top of that, a higher temperature inside the house slows the heat coming into your home, which means you have to spend less money and energy managing it.
In other words, on a 100-degree day, your instincts may be to set the thermostat to 65 degrees, but you won’t really notice a difference from leaving it at 78 — until you check your bills, which will be significantly higher.
“The smaller the difference between the indoor and outdoor temperatures, the lower your overall cooling bill will be,” the Department of Energy explains (opens in new tab).
By turning your thermostat up 7 to 10 degrees for eight hours a day, the site adds, “you can save as much as 10% a year on heating and cooling”. Though it does add that the percentage saved is “greater for buildings in milder climates than for those in more severe climates.”
This guidance has been a longstanding part of the government’s advice, and its counterintuitive nature has always led to a lot of bemusement from homeowners (opens in new tab). But with energy prices soaring, your wallet will thank you if you defer to the experts on this one.