How Much Electricity Does a Portable AC Use (Running Costs)

Portable air conditioners are incredibly useful in that you can move them just about anywhere you want and in any type of home. However, many people wonder, “do portable air conditioners use a lot of electricity?”

That answer is a bit relative, so we’re going to take you through exactly how much you can expect one to use and decide if it’s the right choice for you and your household.

How Much Electricity Does a Portable AC Use?

We mentioned this briefly just a moment ago, but let’s cover how much electricity does a portable air conditioner use in BTUs. BTUs stand for “British Thermal Units,” which is the amount of heat needed to raise the temperature of one pound of water by one degree Fahrenheit at the temperature that water has its greatest density.

On top of BTUs, you’ll also want to know how much electricity does a portable air conditioner use.

Portable AC Unit (BTU)Estimated Electricity Use (kWh)Cost Per Year (approx.)
5000 BTU1.4 kWh$174
8000 BTU2.3 kWh$322
10000 BTU2.9 kWh$704
12000 BTU3.5 kWh$779.52
15000 BTU4.4 kWh$1210

Related Article How Many BTU are in a Ton?

Factors Affecting Air Conditioners Electricity Usage?

There are many variables to consider when we look into how much electricity a specific AC model will use.

  • The AC’s Capacity
    This factor is what will affect energy usage of a portable AC over any other, so make sure you’re choosing the capacity according to the space you’d like to cool. You’ll want around 20 BTUs per square foot of the space in question, also taking into consideration your area’s climate. You don’t want to purchase a model with a higher capacity (thus, using more energy) than you need.
  • The AC’s Efficiency Rating
    It’s not enough to just go off the AC’s capacity; you must also consider the efficiency rating. Look into their SEER (Seasonal Energy Efficiency Ratio) rating, which is the ratio of cooling power per season divided by the number of watts used per hour for a portable AC. As you can imagine, the higher this rating is, the more efficient it will be. You never want to go below a 14 SEER rating, though try to get it towards 25 if you can.
  • The Climate
    Where do you live? Suppose you live in a desert climate like Las Vegas, a particularly humid environment like Miami, etc. In that case, you definitely need to up the power from what you may have purchased if you lived in Oregon, for example. Your AC will have to work harder to cool your home if it’s in a hotter environment.
  • The Maintenance Routine
    How often is your AC unit maintained? We recommend getting it serviced at least every 6 months to keep it running optimally. Just remember that aside from this, you should be regularly cleaning the portable AC or at least clean/change out your filters.
  • The Temperature Settings
    How cold do you like your home to be? Chances are that you want it somewhere around 75 degrees, which is what most manufacturers recommend anyway. If you tend to push it even lower than that – even for a part of the day – it will use more energy.
  • The Insulation
    It’s important to not only consider the climate of where you live but how well-insulated your home is. If it’s poorly insulated, cold air will escape easier, which will mean you have to run your AC harder to cool the space to your liking.

After reading this, you may also be wondering, “Can you run a portable air conditioner continuously?” While you technically can, you likely aren’t going to want to, as it will really run up your power bill.

Factors Affecting AC Electricity Usage

Calculating the Cost to Run a Portable Air Conditioner

When it comes to portable ACs, you’ll find they come in 5,000 BTUs to 15,000 BTUs. We have to look at two things:

  1. .Max power of the AC unit (in watts)
  2. .Price of electricity where you live (in cost per kWh)

One kW is equal to 1000W. The formula to calculate a per-hour cost for running your AC is the following:

Cost x per hour = Power of AC in Watts x Electricity Cost per kWh/1,000

  • Cost to Run 5000 BTU Portable AC – Per Hour: $0.06, Per Day: 0.48, Per Month: $13.44
  • Cost to Run 8000 BTU Portable AC – Per Hour: $0.09, Per Day: 0.72, Per Month: $20.16
  • Cost to Run 10000 BTU Portable AC – Per Hour: $0.11, Per Day: 0.88, Per Month: $24.64
  • Cost to Run 12000 BTU Portable AC – Per Hour: $0.13, Per Day: $1.04, Per Month: $29.12
  • Cost to Run 15000 BTU Portable AC – Per Hour: $0.17, Per Day: $1.36, Per Month: $38.08

*For our calculations, we estimated the cost of electricity in our area as 0.11kWh

Ways to Lower Electricity Bills When Using a Portable AC

While it is important to know around how much you’ll be spending to use your portable AC, these prices aren’t necessarily set.

You can use various methods to lower your electricity bills while running your air conditioner.

1. Buy energy efficient cooling options

Smaller and more energy-efficient AC models come with features that ensure your portable air conditioner is running at the most productive levels possible. Some come with things like timers that will also turn off the machine when the ideal temperature has been reached.

2. The right size for the room

We mentioned this earlier, but make sure your AC unit is rated to suit the size of the room or space in question. This means that it’s powerful enough to cool the room without working too hard, but not too powerful that you’re wasting money.

3. Cool one room at a time

Chances are, you’re probably not going to need to be cooling your entire home at one time. Even if it’s not just you there, you can significantly reduce your electricity costs by just cooling one room at a time.

4. Cooling and heating system

Some portable air conditioners can also function as a heater when the weather starts getting colder! This can help make the investment even more worth it, as it’s essentially a 2-in-1 machine.

5. Keep cool air indoors

While having good insulation in your home is important, it’s not the only factor that will keep your cool air indoors. Make sure doors and windows are closed while running your AC and that you have any air leaks covered with weather stripping or caulk. If you happen to have a fireplace, also check to make sure the damper is closed.

6. Create shade

An air conditioner sitting in direct sunlight will require more energy to cool your space, thus working harder. Place it in a shaded area or create shade with drapes/blinds for it to keep your area cool without making your power bill skyrocket.

7. Take advantage of fans

Fans are often underrated, especially when all we need is our space to be cooled down just a few degrees. Instead of turning on your AC in these cases, turn to a fan as a low-cost alternative.

8. Regular maintenance

We simply can’t reiterate this enough: make sure you’re regularly performing maintenance on your portable air conditioner! Get it serviced by an HVAC professional at least twice a year, as well as periodically changing out or cleaning the filters. Dirty filters cause the AC unit to work harder unnecessarily, which will also raise your electricity bill.

People Also Ask (FAQ)

Can you run a portable AC all day?

You definitely can; there’s no limit to how long you can keep it running. However, it’s likely not necessary and is just going to cause your electricity bill to be more expensive.

Are portable air conditioners cheap or expensive to run?

Nope! Actually, that’s another one of the most appealing features of having a portable air conditioner! On average, it uses around 1/8 of the electricity a central air unit does.

How many hours a day should portable AC run in summer?

Try to hit around 15-20 minutes at a time. On particularly hot days, you may want it running just about all day long. It depends on the temperature and your own preferences.

Can you use a portable air conditioner in a room without a window?

Yes, definitely, just simply invest in a windowless air conditioner! Or simply vent it out through the door/balcony, which is more convenient for many.

Use Portable AC Without Window


Now that you know just about everything you need to know about portable air conditioner electricity cost and operations, do you feel confident about purchasing one? Trust us when we say you won’t regret it! Be prepared to feel cool and dry all summer long without feeling the scorch of high electricity bills!

Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.