How Many Watts Does It Take To Run A House? (2024)

The Size of Your House

If you have a larger house, it will require more electricity than a smaller one. You’ll have more rooms to which you have to run electricity for lighting and small appliances. The greatest costs, however, will come from the extra heating and cooling. The larger the space, the more you’ll have to spend to keep it at a comfortable temperature.

How Many People Live in Your House

The more people who live in your household, the greater the electricity costs will be. More people means an increased use of appliances, lighting and temperature regulation mechanisms. All of this will lead to your household using more wattage.

The Number and Type of Electrical Appliances

If you have more appliances in your home, you’ll use more electricity, particularly if those appliances are ones that require a lot of power to run. The climate you live in can affect what kinds of appliances you’ll need—if you live in a warmer part of the country, you’ll likely need to use central cooling more frequently than those who live in temperate areas. If it gets very cold where you live, central heating will prove costly, as it requires more wattage than space heaters.

How Often You Use Electrical Appliances

If you find yourself using electrical appliances frequently, the number of watts you use in your house will be greater. In order to keep wattage low, keep appliance use to a minimum. Coordinating electrical appliance use with other people who live in your household, such as combining loads of laundry or only running the dishwasher when it’s full, can cut down on wattage use.

Mathematical Formula to Determine How Many Watts Your House Need

To determine the number of watts your house is using, you’ll need to know two things: the number of watts it takes to power your appliances, called running watts, and the number of watts it takes to start your appliances, called starting watts.

To determine how many watts your generator requires to run all your home appliances, you’ll need to add up the watts they use to run continuously. Then, you’ll add the highest number of starting watts your appliances use. For example, consider that you have the following:

• An air conditioner that requires 1,100 running watts and 1,700 starting watts
• A refrigerator that requires 800 running watts and 2,400 starting watts
• A television that requires 500 running watts and 0 starting watts
• A tea kettle that requires 600 running watts and 0 starting watts

You’ll add your running watts to get 1,100 + 800 + 500 + 600 = 3,000. You’ll then add the highest starting wattage of all your appliances to that total. In this case, the highest starting wattage is 2,400 from the refrigerator. So you’ll need a generator with at least 5,400 starting watts and 3,000 running watts.

According to data from 2020, the average amount of electricity an American home uses is ​​10,715 kilowatt-hours (kWh). If you divide this number by 12 (months in a year), the average residential utilities customer uses 893 kWh per month.

If you divide 10,715 kWh by 365 (days in a year), you’ll get the average number of kilowatt-hours used per day, which is 29.36 kWh. If you multiply that by 1,000, you can find the energy consumption in watts that occur in 24 hours, or 29,360 watts. If you then divide that by 24, you’ll find that the average household requires 1,223 watts of power.

Again, this is only an average. You will need to determine your household’s personal electricity usage to decide what size generator is right for you.

Kitchen Energy Use

Here are a few appliances you typically see in kitchens along with how many watts they use on average:

• Dishwasher: 1200 to 1500 watts
• Microwave: 966 to 1723 watts
• Oven: 2150 watts
• Coffee Maker: 800 to 1400 watts
• Refrigerator: 150 to 400 watts

The kitchen has a large number of appliances, and a good portion of your wattage use is likely to come from this part of the house.

Living Room Energy Use

Living rooms will likely require the fewest watts, as they have the fewest number of appliances. Plus, the appliances in a living room also don’t take that much energy to run. Here is an estimate of how many watts it’ll take to run your living room:

• Laptop: 50 to 100 watts
• Flat screen TV: 60 to 115 watts, depending on the model, size and age

Laundry Room Energy Use

The laundry room will probably be the part of your house with the second highest number of watts used, due to the large amounts of energy required to power the washer and dryer:

• Washing Machine: 500 watts
• Dryer: 1,000 to 4,000 watts

Central Heating and Cooling Systems

Although not confined to any particular room, your heating and cooling systems will likely take up the most energy:

• Central Heating Furnace: 340 watts
• Portable Electric Fan Heater: 2,000 to 3,000 watts
• Central Air Conditioner: 1,000 to 4,000 watts
• Window AC Unit: 900 to 1,440 watts

Although it’s fairly simple to calculate the number of watts your appliances use, it may be useful to have someone come out for a home energy audit. This type of audit will not only calculate the number of watts your house uses, but can also help make your home more energy efficient.

The auditor will check your windows and walls to determine if there’s anywhere temperature regulated air from inside the house could be leaking out. It could help cut down on your heating and cooling costs.