Moving to sunny Texas from frigid Minnesota brought dreams of outdoor living, at least for more than four months out of the year. So I put a home office in the garage. We have a mosquito screen and a home theater, and my spouse and I sit out there even when the temperature dips into the 40s. How? Hello, space heater.

Space heaters direct warmth right at the user, making them a viable option to boost a chilly room or substandard heating system. But as Christmas 2022’s “bomb cyclone” proved, a space heater can only do so much. We moved inside.

Do you have a space heater? Do you know how much it costs to run? Read on to find out your space heater’s energy usage.

How Many Watts Does a Space Heater Use?

Electric space heaters for home use are usually rated for 1,500 watts at max power. That’s according to Ace Hardware, in partnership with Lasko, maker of home comfort products. (Putting your heater on a low setting will use less energy.)

How Much Electricity Does a Space Heater Use?

A 1,500-watt electric space heater draws 12.5 amps of electricity at 120 volts. (Watts = amps x voltage.) But what does that mean for your electric bill?

The utility doesn’t charge you for electricity in amps. It charges you for power consumed, and that’s measured in kilowatt-hours (kWh).

To figure out space heater energy usage in kilowatt-hours, and therefore how much it costs to run it, take the space heater rating in watts and multiply it by how many hours per day you use it. Then divide that number by 1,000 to convert to kWh.

Let’s say you have a home office in your garage like I do, and you use your 1,500-watt space heater eight hours per day. So 1,500 watts x 8 hours per day / 1000 = 12 kWh. As of November 2022, the average cost of electricity in the U.S. was $0.163 per kilowatt-hour, according to the U.S. Bureau of Labor Statistics. So 12kWh x $0.163 = $1.96 per day.

Bottom line: Your 1,500-watt space heater running eight hours per day will cost you about two dollars per day to operate, depending on your electricity rate.

Fhm How Much Electricity Does A Space Heater Use?Family Handyman

Do Space Heaters Use a Lot of Electricity?

It depends on how you look at it.

Heat producers like dryers, resistive and infrared space heaters and furnaces generally use more energy than electronic devices like computers. Because we know how to calculate the cost of your space heater energy usage, let’s compare those numbers to other appliances and devices in your home.

Television

Check the back of your TV to see how many watts it typically uses. Mine is 73 watts, about average for its size. You guessed it! A 73-watt television consumes much less power than a 1,500-watt space heater.

Running four hours a day, a 73-watt TV costs about a nickel per day to operate or a little more than $17 per year. And that doesn’t include vampire energy. In comparison, a 1,500-watt space heater running four hours a day costs nearly $1 per day, or about $88 for three months of daily winter usage.

Laptop computer

Laptops draw power through their charger and use the battery when not plugged in. A laptop’s energy use varies depending on what it’s doing. Checking email will use significantly less energy than running a game.

A 96-watt laptop charging two hours a day costs about three cents daily, or $11.42 per year.

Vacuum cleaner

According to M Healthy, a vacuum cleaner uses 1,000 to 1,440 watts, although models vary (mine is only 840W). To find your specific energy usage, look at the label on your vacuum. Multiply the amps times the voltage to get the power consumed (in watts), then use the formula.

A 1,000-watt vacuum cleaner used one hour per week consumes one kWh of energy. At the average rate of $0.163 per kWh, the vacuum cleaner costs about $8.50 per year to run.

Clothes dryer

The average family does 300 loads of laundry per year. That’s about $245 per year for a 5,000-watt clothes dryer, making it one of the biggest energy users in your home. A 1,500-watt space heater running for the same 300 hours would cost $73.35 at the average electricity rate cited above.

FAQs

How can I reduce the energy consumption of my space heater?

You can use two basic strategies:

  • Run the heater intermittently. If your heater has a timer, set it to automatically switch off the heater after a predetermined period, then wait until you really need heat before turning the heater back on. If your device has no timer, you can do this manually.
  • Lower the thermostat, if your heater has one. Many space heaters have energy-saving (ECO) settings which allow them to run at lower wattage. Using the lowest setting can cut electricity usage almost in half.

Besides these strategies, you can also save on energy costs overall (not just the cost of using your space heater) by adding more insulation to your house.

How long can I let a space heater run continuously?

It takes about four to six hours for most models. Continuous operation risks overheating and fire, especially if you’re sleeping or not in the same room as the heater. If your heater has been running for several hours, you should turn it off if you notice any of the following:

  • strange odors;
  • unusual sounds;
  • fluctuations in heat output;
  • frequently tripping circuit breakers.

How to Choose the Best Space Heater

Whether you’re heating a room, garage, or greenhouse, learn how to choose the right space heater while keeping safety and efficiency in mind.

Sources

Author
Ally Childress
Ally Childress writes practical, informed stories and how-to guides for Family Handyman and Reader’s Digest. An experienced electrician, Ally's beat naturally includes electrical and construction topics. She also tackles cleaning, gardening, technology, bugs and anything else you can throw at her. She has a knack for finding just the right subjec...
Read More
Ally Childress