Will setting my AC to 78 actually save me money? What to know in California heat
As parts of California brace for triple-digit temperatures and forecasts call for a hotter-than-usual summer, many residents are preparing for higher air-conditioning use — and potentially higher energy bills.
A heat wave is sending temperatures soaring into the triple digits across parts of Northern California and the Central Valley, with highs reaching as much as 102 degrees in Sacramento.
“The summer months often bring an unwelcome surprise of high bills for many PG&E customers, particularly in the Central Valley where outside temperatures are well over 100 degrees,” Pacific Gas and Electric Co. said.
What temperature should you set your thermostat to in order to save money?
Here’s what California energy experts recommend:
What’s the best thermostat setting to save energy?
According to PG&E, setting your thermostat to 78 degrees during hot weather can help reduce cooling costs while keeping your home comfortable.
“Every degree above 78 represents approximately 2% savings on cooling costs,” the company said.
When temperatures climb above 100 degrees, PG&E said, air conditioners are “working very hard to achieve” cooler indoor temperatures, which can drive up electricity use.
“Consider using a programmable or smart thermostat, which lets you cool (or heat) your home when energy demand is lower and costs are typically reduced,” the utility company wrote in a statement to The Sacramento Bee.
Smart thermostats can save the average California customer $50 to $78 a year, according to PG&E.
The Sacramento Municipal Utility District also recommends setting thermostats to 78 degrees as the ideal indoor temperature during summer.
“You’ll save around 5% to 10% on cooling costs for every two degrees you raise the temperature,” SMUD said.
According to the U.S. Department of Energy, homeowners can save up to 10% a year on cooling costs by adjusting their thermostat 7 to 10 degrees from its normal setting for about eight hours a day.
What are the best ways to lower summer utility bills?
In addition to adjusting the thermostat, energy experts recommend reducing electricity use during peak-demand hours, when rates are often highest.
“Electricity use is highest in the late afternoon and evening,” PG&E said.
Both PG&E and SMUD said customers should limit energy use between 5 p.m. and 8 p.m. through Sept. 30, when summer rates are in effect.
Blocking direct sunlight into your home can also help reduce cooling costs.
Closing blinds, shades and curtains during the hottest part of the day can keep indoor temperatures lower and reduce the strain on your air conditioner, according to SMUD.
“Sunlight passing through windows heats your home and makes your air conditioner work harder,” PG&E said.
How can I keep my home cool while saving on costs?
According to the U.S. Department of Energy, other energy-saving tips include:
- Keeping air vents clear, so your system can work efficiently.
- Using fans to cool your home.
- Unplug devices when not in use.
- Cleaning HVAC filters every month during peak cooling or heating seasons.
- Sealing air leaks by replacing old caulking and adding weatherstripping around windows and doors.
- Checking insulation and replace any that’s damaged to help keep cool air inside.
- Do energy-intensive chores, such as washing dishes and laundry, until off-peak hours.
- Inspecting your equipment often to make sure everything’s working properly.
Avoid these common electricity-wasting mistakes
“During hot weather, there are a few common energy myths that can increase energy use and costs,” PG&E said.
According to PG&E, these include:
- Lowering the thermostat to 60 degrees cools your home faster.
- Keeping fans running in empty rooms.
- Devices that are plugged in but turned off don’t use energy.
- Saving energy requires expensive home upgrades.
This story was originally published June 11, 2026 at 9:00 AM with the headline "Will setting my AC to 78 actually save me money? What to know in California heat."
