At Home with Lisa: Fans VS Air Conditioners

A friend of mine asked me a question the other day. “How much energy does air conditioning use as compared to a fan?” she asked.

We all know that fans use less energy—they don’t cool the temperature of the room, they just cool the people by helping to evaporate sweat. But I didn’t realize how much less until I started researching the topic. I looked through Avista’s Energy Guide and found that a portable fan uses about 7.3 kilowatt hours a month, or $0.73 a month. A room air conditioner can use about 225 kilowatt hours a month, or $22.50, if you run it for five hours a day. That’s a huge difference.

I also found that if you use a fan and an air conditioner at the same time, you can turn the thermostat down on the air conditioner a few degrees and be just as cool, making the air conditioner a little more efficient.

Lisa, an Avista customer, bought her 1910 house because she loved the old-world character, some of which doesn’t make her house very energy efficient. Lisa is sharing her experience on taking some simple do-it-yourself improvements to inspire others to do the same. You’ll find her stories right here every Tuesday morning.

Find more tips for keeping cool this summer.

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  1. At Home with Lisa
  2. Energy Saving