We're into the first real hot stretch of the year, 94 tomorrow and low-to-mid 90s most of the week, which means your AC is about to start running like a mad man. It also means the bill that shows up next month is going to look different than the one you got in May. Idaho Power charges more for electricity in the summer than the rest of the year, rates went up again this year, and your system is simply running more hours. Put those together and a lot of folks get a July bill that makes them look twice.
So this week, we are just going to talk about what we tell our own neighbors about staying comfortable without dreading the bills that come in. Hopefully we can help save you a few bucks this summer so you have more ice-cream money for LoveJoy's or Reed's Dairy.
What should I set my thermostat to in the summer?
Around 78 degrees when you're home is the usual sweet spot when it comes to affordability and comfort. Every degree you drop below that adds a few percent to your cooling costs, and it adds up fast over a long valley summer. I personally like it cold, so I don't mind paying extra for the AC bill when it comes through because I want it to be 70 degrees at the warmest! It's a trade off I'm willing to make.
If 78 sounds warm, give it a few days. Most people acclimate quickly, especially with a fan running. And when you're not home, let it climb higher rather than holding it cold for an empty house.
Does cranking it way down cool the house faster?
Absolutely not. This one quietly costs people money. Your AC cools at one speed whether you set it to 75 or 60. Dropping the thermostat to 65 doesn't get the house to 75 any quicker, it just means the system keeps running long after you're comfortable, and half the time it overshoots and you end up shivering.
On especially hot days, it's common that AC systems will never fully satisfy. If you try to set your thermostat to 62 degrees, it probably will never get there and just keep running. Set it where you actually want it and leave it there.
Should I turn the AC off completely when I leave for the day?
Better to let it drift up than shut it off. Setting it to around 82 to 85 while you're gone, then back down before you're home, saves real money. Turning it fully off in 95-degree heat tends to backfire. The house bakes all day, and the system then has to run flat out to claw all that heat back out, which can cost you more than you saved.
A programmable or smart thermostat handles this for you automatically, and it's one of the few upgrades that genuinely pays for itself over a summer or two.
When is electricity most expensive around here?
Summer is when electricity is the most expensive, with Idaho Power's rates running higher from June through September. And if you're on their optional Time-of-Use plan, the evening on-peak window (currently 7 to 11 p.m. on weekdays) can cost several times what the same energy costs off-peak. The move there is to pre-cool your house earlier in the day and ease off during that evening window. It's worth checking which plan you're actually on at idahopower.com before you change your habits.
Two more notes: Idaho Power's residential pricing is tiered, so the more you use, the higher the rate climbs on those extra kilowatt-hours, another reason small savings stack up. And their A/C Cool Credit program pays you a bill credit for letting them briefly cycle your AC during peak demand on the hottest days. If you don't mind a short cutback when the grid's strained, it's close to free money.
What else actually lowers the bill?
The thermostat gets all the attention, but these do real work:
- Close the blinds on the sunny side of the house during the day. It's generally going to get hotter on the west side of your home. Our high-desert sun is no joke, and a bank of west-facing windows in the afternoon can heat a room faster than your AC can cool it. This one's free and it's bigger than people think.
- Run your ceiling fans, but only in rooms you're in. Fans cool people, not rooms, so a fan running in an empty room is just spinning your money. You can get away with a slightly higher thermostat in this case.
- Change your filter monthly in summer. A clogged filter chokes airflow and makes the whole system work harder for less cooling.
- Set the fan switch to "Auto," not "On." On "On," the blower runs nonstop even when the system isn't actively cooling. These systems know when to turn on and off. Let them do what they're made to do.
- Keep the outdoor unit clear, and hose the cottonwood off it. A unit that can't breathe runs longer to do the same job.
The short version
Set it to 78 when you're home, let it drift up when you're out, close the blinds against the afternoon sun, change your filter, and if you're on Time-of-Use, go easy during the evening peak. None of it costs much, and together it can take a real bite out of the summer bills.
If you've done all that and your bill still jumps hard, that can be a sign your system is working harder than it should, but that's a conversation for another day.
Stay cool out there.
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