The fan by itself doesn't use much energy. It's the cooling part of the AC system that uses most of the power.
Dirty filters, duct leaks, failing parts (motors, capacitors, etc.), low refrigerant, lack of maintenance, old system, and a bad install are all reasons your air conditioner itself will cause high electric bills.
Turning the air conditioner off when you're not home saves energy. That's because it runs most efficiently at full speed, and running it all day—even at a less powerful setting—requires more energy overall. But using an air conditioner to cool your home contributes to global warming.
A typical AC fan motor uses about 500 watts when it's running. Therefore, if you run the fan continuously for a 30-day month (720 hours), you would use 360,000 watt hours (720 x 500) or 360 kilowatt hours (kWh). Therefore, the fan uses about 360 kWh per month in the ON mode.
Keeping your fan on AUTO is the most energy-efficient option. The fan only runs when the system is on and not continuously. There is better dehumidification in your home during the summer months. When your fan is set to AUTO, moisture from cold cooling coils can drip and be drained outside.
Every degree above 78 saves about 2 percent on your bill, while every degree below costs an extra 6 percent. Fans are cheaper to run than air conditioners, and can be used in place of air conditioners or along with them to save money. If you have a ceiling fan, run it at the same time as the AC.
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. And don't drop it down to a super-low temperature after being gone all day.
If you left the unit on during the day, it would turn on and off throughout the day. If you live in a colder climate where your HVAC does not have to work as hard to maintain a comfortable temperature, turning your air conditioner off during the day could help you save money.
The harder the air conditioner works, the more energy and electricity it uses. If your unit needs repair, then it may also cause your unit to work overly hard. For example, having a leak that causes Freon to pour out will contribute to a higher electric bill.
No, it is in fact not bad to keep turning your AC unit on and off. It might seem like a waste of energy to keep tampering with the AC settings throughout the day, but it can actually save you money on your energy bill. Air conditioners work best at cooling and dehumidifying when they run at full speed.
Turning Your Air Conditioner On & Off vs.
Since air conditioners use more energy when they cycle all day, it is cheaper to let your system operate at full capacity when you're home instead of running it at a lower capacity all day. The more energy you use, the more money you'll pay in monthly utility bills.
In fact, windows and doors can account for 20% or more of your total heat or cool air loss. That basically means upgrading your windows and sealing your doors could make your AC system 20% more efficient. That's quite an important amount.
Especially compared to a central AC unit, window units don't use very much electricity. A window AC requires on average 500 to 1,440 watts to run, while a central unit uses upwards of 3,500 watts. If you only need to cool a small space, window ACs are much more cost effective than central AC units.
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.
Studies have shown that, on average, shutting off your air conditioner at night will reduce your total cooling costs by somewhere around 30% compared to leaving it turned on 24 hours a day.
Benefits of keeping a relatively constant temperature
Alongside substantially lowering your energy costs and extending the lifespan of your AC unit, there can be additional benefits to your home such as keeping your hardwood floors and wooden furniture in better condition.
Fans work by creating a wind-chill effect on your skin so you feel cooler. Raising the temperature and using a fan can help you use less energy running your air conditioner; you may even be able to avoid using your air conditioner altogether.
"It's more energy efficient to keep the unit on but turn the temperature setting up," she advises. Turning off the AC unit during the day is not necessarily a bad thing — it is a myth that the AC unit has to work extra-hard to cool off a hot house.
While running your air conditioner will cool your home, it consumes a lot of energy, leading to higher electricity bills. Yet not using the air conditioner isn't practical.
Fans don't cool down the room as much as an AC does, but they're definitely cheaper to run and can help save you money in the long run.
A 220-volt supply can transmit the power more cheaply because a smaller current is needed, and so you can use thinner cables and/or lose less energy through heat generated in the cables.