Set the thermostat as high as comfortably possible during hot weather. The less difference between the indoor and outdoor temperatures, the lower your cooling bill will be. Keep your house warmer when you aren't home during the day, but cooler when you come home at night.
The short answer is yes, it's more cost-effective to keep your air conditioner on all day. However, don't take this as a green light to crank it up to the max 24/7! There's a smart way to go about it, which we'll delve into in a moment. So, why is it cheaper to leave your AC on?
According to the Department of Energy1, 78° Fahrenheit is the sweet spot for air conditioners to balance energy savings and comfort when people are at home and need cooling. But in reality, this is a question that doesn't have a “one size fits all” answer.
Since 72 degrees is generally agreed upon to be an ideal indoor temperature, most people would probably still feel comfortable setting their AC units slightly higher than this, perhaps at around 75.
For many of us, 70 degrees is the ideal indoor temperature, but when it is close to 100 degrees outside, your AC unit will be working quite hard to meet these expectations. Consider setting your thermostat at 75 degrees to 80 degrees in your home if the outside temperature is approaching triple digits.
The average cost per kWh in the US is currently $0.11, according to the Energy Information Administration (EIA). This means an AC unit could cost you from $5.17 to $5.94 per day to run. Or about $155-$178 per month you're running it.
Although many people believe that it is more costly to turn your AC on and off vs. leaving it on, this is entirely false. People often base this belief on the idea that powering on your system requires a burst of energy, so leaving it running would minimize energy usage by reducing these bursts.
Increase the thermostat
If you are just as comfortable with your thermostat one or two degrees higher than you currently have it set, go ahead and turn it up. Even a one degree difference will have an impact on your energy bill. Many recommend 78 degrees as a good temperature for air conditioners to run efficiently.
Your air conditioning system is one of the biggest culprits behind skyrocketing electric bills. When your air filter is dirty, refrigerant levels are low, your thermostat is faulty or you lack proper maintenance, your A/C system can end up using a lot more energy than it should.
Keep your programmable thermostat set as high as is comfortable (the DOE recommends 78 degrees Fahrenheit), and when you're away from home, set the temperature even higher. You can trim 10 percent off your energy bill by setting your thermostat by 7 to 10 degrees higher for eight hours a day, the DOE estimates.
Keeping the temperature between 75 and 78 degrees will reduce the risk of overworking your heating, ventilation and air conditioning system, he said, and keep your electrical costs down.
On an average summer day, a general guideline is that your AC should operate between 12 and 16 hours. However, several factors can influence this, including the outdoor temperature, desired indoor temperature, the size and type of your unit, and your home's energy efficiency.
Eco or energy-saving mode
This is the ideal mode for users looking to save up on energy bills by toning down the performance of the AC and its compressor. Eco-mode uses less electricity by automatically adjusting the fan speed and temperature, while still maintaining a comfortable level of cooling.
As it turns out, the most efficient way to keep your home cool and the bills low is to leave the AC running—ideally, with the temperature turned up toward the upper 70s.
How much does air-conditioning cost to use? On average, an air conditioner costs between $0.06 and $0.88 per hour to use. Let's see how much air-conditioning costs every month (assuming it runs for 8 hours per day). The cheapest option is $14.40 per month and $211.20 per month on the high end.
You can also reduce your energy costs significantly by raising the temperature while you are at work, away from home, or asleep. For the greatest savings, consider setting your thermostat to: About 78 degrees while you are at home. About 82 degrees while you are sleeping.
The California Energy Commission recommends that homeowners set their thermostat to 78 degrees when they're home and 85 degrees when they're away from home during the summer.
It's true that air conditioners do have limits when the outside temperature is extreme. This means that your air conditioner may be able to keep your home at 77 or 78 degrees when it is 104 degrees outside.
In general, 80 degrees is too hot for a house if people are inside. However, if people aren't home during the day or for vacation during the summer, an indoor temperature of 80 degrees can save energy until you return and lower the temperature.