How Many Watts Does a Window AC Use

How many watts does a window AC use?  A window AC uses about 500 to 1,500 watts of energy on average.  Air conditioners are an essential electronic appliance in many households, especially in the summer, as they maintain a comfortable temperature on hot days.  It is important to find how many watts a window AC uses so that you can know exactly how much it will add to your electricity bill and whether this will be affordable.

In this article, we will discuss finding your window AC unit wattage and estimating energy consumption and its cost.  So let us move on.

How Many Watts Does A Window AC Use
Photo Credit: Unsplash

Key Takeaways About Window AC Wattage

  • How many watts a window AC usedepends on various factors, including the size of the AC, the area to cover, and how hot the weather is.  A large window AC can use around  1,440 watts, a medium-sized window AC uses 900 watts, and a small AC unit uses about 500 watts.
  • Generally, an air conditioning unit runs for eight to nine hours daily during the hot summer days.  Eventually, different sizes of window ACs can use 500-15000 watts of power per hour.
  • We can see that windows AC can use moderate to high amounts of energy, and thus it is a bog overload on your electricity bill.  Converting to solar generators or solar panels can save you a lot of money in the long run. Jackery has a line of safe, reliable, and efficient solar generators that can run most of your household appliances for a good amount of time.

How Many Watts Does A Window Ac Use?

Definition Of BTU, Watts, Running Watts, Watt-Hours

  • A British thermal unit (BTU) is a unit to measure the heat content of energy sources.  In simpler terms, btu is the heat required to increase the temperature of one point of water by one degree Fahrenheit at its greatest density.
  • A Watt is a measuring unit for the rate of electricity consumption.  It can be calculated by;

Watts = Volts * amps

 A kilowatt is 1,000 watts.

  • The running watts of an appliance is the continuous watts that keep the electronic device running.  It is also known as rated watts.
  • Watt-hour (Wh)measures the energy consumed by a device over a certain time.

BTU To Watt

BTU to watt conversion is done through a formula.  BTU to Watts can be calculated by multiplying the BTU/hr by 0.29307107.

1 BTU is equal to 0.293 watts

Watt= BTU * 0.29307107


How many watts are in 24,000 BTU?

We know that 1 BTU is equal to 0.293W.

 Watt = BTU * 0.29307107

Watt = 24,000 * 0.29307107

Watts = 7,032 watts

That means that 24,000 BTU is equal to 7,032 watts.

How Many Watts Does A Window AC Use

How many watts a window AC uses depends on its thermostat, size, and duration of its working.  An average 5,000 BTU air conditioner at its full capacity consumes 500W of energy.  The following table shows the estimated power consumption of different sizes of window ACs.

Window AC BTU

Window AC Estimated Watts

Length of Time Powered (hours)

Estimated  power needed daily (Watt-hours)

































How Many Watts Does A Small Window AC Use

A small window AC uses 500 watts on average.  If you know the BTU rating of your AC, then you can easily calculate the wattage.  We have already discussed the BTU-to-watt conversion in the above section.

How To Calculate How Much Energy Your Window AC Uses

You can find the BTU rating of your air conditioner in your appliance's manual or on the sticker placed on the AC.  Usually, you will see the BTU measurement of your AC, and then you can convert it to watts and watt hours, the unit you use to calculate your electricity bill.  So let us see the conversion.

How many BTUs are there in 1 watt-hour?

1 BTU = 0.29307107018321-watt hours

1 BTU = 0.29307107018321 watt hours (1*0.29307107018321)

2 BTU = 0.5861421403 watt hours (2*0.29307107018321)

5 BTU = 1.47 watt hours (5*0.29307107018321)

What Size Generator Do I Need For Window AC

You can run a small to medium window AC unit with a 1000-watt generator.  A bigger generator of around 2000 watt power can run a large window AC unit.  Solar power generators are a new alternative to regular gas generators because they are environment-friendly, noise-free, and low-cost.  Though there is a high upfront cost, after that, there is no fuel cost as it draws energy from the sun, and also, the maintenance cost is very low.

How many watts does a window AC use from a generator?  A window AC is in the range of 5000 BTU to 14000 BTU.  The running watts required for a 5000 BTU air conditioner are around 450.  An 8000 BTU air conditioner may need about 715 watts, and 1250 watts are required for a 14000 BTU air conditioner.  You can estimate your window AC wattage in the above section and decide the best solar generator option.

Jackery Solar Generator 1000 Pro is the best option for an 8000 BTU window air conditioner.

Jackery Solar Generator 1500  can run a large window AC easily.

Jackery Solar Generator 2000 Pro is a more practical option because it can simultaneously support multiple appliances on a solar generator.

Best Solar Generator for Window AC

The Jackery solar generators are the best for window AC because they have a wide range of options with multiple energy capacities.  These generators have very fast charging and support long hours of working.  The best solar generators for window AC are discussed below.

Jackery Solar Generator 2000 Pro (Explorer 2000 Pro + SolarSaga 200W)


Jackery Solar Generator 2000 Pro


The Jackery solar generator 2000 Pro comes with 2,160 Wh capacity, 2,200W AC power, and 4,400W peak power.  You can run a large window AC on this generator and other appliances.  Its dual battery protection and four temperature core detectors keep your appliances safe and secure from fluctuations.

Jackery Solar Generator 1500 (Explorer 1500 + SolarSaga 100W)

Jackery Solar Generator 1500

The Jackery solar generator 1500 offers 1534Wh capacity with 1800 running wattage.  It can run a large to a medium window air conditioner.  It has very fast solar engineering supported by Solarpeak™ technology, with which it can charge up to 80% within 4 hours with 4 SolarSoga 100W solar panels.

Jackery Solar Generator 1000 Pro (Explorer 1000 Pro + SolarSaga 80W/200W)

Jackery Solar Generator 1000 Pro

The Jackery solar generator 1000 Pro fully charges in 1.8 hours.  It is compact and portable, so you can use it for indoor and outdoor power generation.  Its integrated battery system monitors and protects the battery life to safeguard your equipment from fluctuations.

How to calculate the working hours:

Working time = Capacity Wh * 0.85 / operating wattage of your TV

For example, a small window AC takes 500W.

A Solar Generator 1000 Pro working time will be 1002Wh * 0.85 / 500w = 1.7 hrs.

The following table summarizes how long a Jackery solar generator can support your windows AC.

Jackery Products

Portable Power Station Capacity (Watt-Hours)

Outputs Ports

AC Wattage

Supported Working Hours

Jackery Solar Generator 2000 Pro (Explorer 2000 Pro + SolarSaga 200W)

2160Wh (43.2V 50Ah)

  • AC Output,
  • USB-A Output,
  • USB-C Output,
  • Car Port



Jackery Solar Generator 1500 (Explorer 1500 + SolarSaga 100W)

1534Wh (25.2V, 60.9Ah)    

  • AC Output Port,
  • USB-A Output Port,
  • Quick Charge 3.0 Output,
  • USB-C Output,
  • Car Output



Jackery Solar Generator 1000 Pro (Explorer 1000 Pro + SolarSaga 100W)

1002Wh (43.2V 23.2Ah)

  • AC Output Port,
  • USB-A Output Port,
  • USB-C Output Port,
  • Car Port



The running hours we have listed above are the solar generator support hours when they are fully charged.  Installing solar panels with your solar generators ensures that you keep running your AC without additional fuel costs. 

FAQ About Window Ac Wattage

1.  Will a 2000-watt generator run an air conditioner?

A 2000 running watts generator provides enough power to run a medium to large window AC without any problem.  However, it is important to know that the running watts are lower than the starting watts.  We need high power for a few seconds when the AC starts, so we need to consider this wattage too.

2.  Can a 1000-watt generator run a window air conditioner?

A 1000 watts generator can easily support 500-600 wattage window ACs.  We are stating a smaller wattage because an AC needs 50% to 100% additional power to support inertia at start-up.

3.  Will a 2000-watt generator run a 5000 BTU AC?

A 5000 BTU air conditioner needs 1456 watts which a 2000-watt generator can easily support.

4.  How many watts does a window AC use?

A window AC unit uses between 500 to 1,500 watts of electricity.  A medium size window uses 900 watts of electricity.  Using this AC for 8 hours will consume about 200 kilowatt-hours of electricity each month.


Air conditioners are essential electronic appliances for people in hot summer areas.  It is important to estimate how many watts a window AC use because it helps you to estimate the electricity bill.  Also, if you want to save on electricity costs, then solar generators of adequate capacity help you save money with an environmentally friendly solution.

1 comment

  • Chris

    Will a jackery power a small window unit while its charging? Solar or plugged in to a 120. If solar how many panels are recommended to run the AC a full 8 hrs. We are full time van lifers living in Texas and looking for solutions.

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