You turn on the lights, watch TV, and run the air conditioning without giving much thought to how much electricity you are using. But a high energy bill, a power outage, or the purchase of a backup battery might make you reconsider your home’s energy needs.

The average US home consumes nearly 11,000 kilowatt-hours (kWh) of electricity a year, 13 times more than in 1950. On average, Americans spend between $900 and $2,000 per year on electricity and prices are expected to increase by 2.8% in 2021.

The type of lightbulbs used, the amount of water being heated and cooled, and the number of appliances used all contribute to how much energy your home will use during a given day. Additionally, how much electricity your house uses will vary depending on the time of year, especially if you live in a warmer or colder climate.

How can you calculate your home energy needs? You can start by viewing your last few energy bills. Then, with a little bit of math, work backwards to figure out which aspects of your lifestyle require the most electricity.

What uses the most electricity in a home?

Energy consumption varies between households. The figures below are estimates based on the U.S. Energy Information Administration’s Annual Energy Outlook (AEO) estimates for 2020, other trusted sources, and calculations based on the average US electricity rate. What you use and spend depends on many variables including appliance efficiency, running time, outside temperature, and your local energy rates.

Cooling and heating

Space cooling and space and water heating take the largest share of residential energy use, totalling 42% of energy use in a typical US home. Space cooling appliances such as air conditioning (AC) units make up about 16% of energy consumption; space heating systems account for more than 14%, and water heating makes up nearly 12%.

Compared to other appliances in the home, cooling and heating systems are inefficient. A central AC unit will use between 1,000 W and 4,000 W and space heaters between 2,000 W and 5,000 W. A 3,500 W HVAC air conditioner uses 850-1,950 kWh a month on average, which could equate to more than $250 a year.

As for the cost of home temperature control, estimates that heating makes up 42% of your bill in cooler months. Houses in the South, where weather is more extreme, generally have a higher need for cooling and heating and therefore consume more electricity.

Fridges and freezers

Refrigerators and freezers make up around 7.1% of energy consumption in US homes. This makes them the most significant sources of energy consumption after space and water heating units, even though they are more efficient than 50 years ago. Your typical refrigeration appliance will use anything from 50 W to 400 W, with freezers consuming the least and fridge-freezers consuming the most.

Your typical refrigerator costs around $80 per year to run on average, and a freezer costs around $70. You can expect to pay less for your second refrigerator than your main one because second refrigerators typically account for 18% of the total average refrigeration consumption.

Additional Appliances

This category is responsible for 41.3% of energy use in US homes. It includes clothes washers and dryers, dishwashers, stoves, computers, and miscellaneous appliances. Tumble driers can burn around 2500 W, dishwashers consume around 1500 W, and clothes washers use about 500 W.

Lighting: A Tale of Two Lightbulbs

Lighting and digital entertainment equipment respectively account for 4.1% of average annual home energy use. Older bulbs use more energy than their modern equivalents. For example, continuously running a 100 W incandescent light bulb consumes nearly 900 kWh per year and costs around $120. A LED bulb that emits the same light only uses 140 kWh and costs under $20. If you light every room of a five room house with a LED bulb continuously for a year, you’d use 700 kWh of energy and pay around $100.

Digital Entertainment

Digital entertainment equipment includes televisions, video games consoles and cable boxes. TVs typically consume anything from 20 W to 300 W of energy. Watching shows on a 300 W TV for four hours a day would consume around 438 kWh per year and cost you around $60. Gaming consoles can use between 40 and 289 kWh per year and add nearly $40 to your yearly bill, depending on the device and usage. Many electronic devices also consume energy on standby.

How to complete a simple energy audit

You can get a better idea of how much energy your specific appliances use in a few steps.

How much energy an appliance uses per day

For this step, you need to convert watts to kilowatt-hours per day. Locate the appliance’s wattage, usually found on the appliance or in its manual. Multiply the wattage by the number of hours used per day, and divide the total by 1000.

(wattage x hours used per day) / 1000 = kWh per day

How much your appliance costs to run per day

Convert kilowatt-hours to dollars by multiplying the kWh per day by your local electricity rate to get the day rate.

(kWh x electricity rate) = cost per day

To work out your annual usage or rate, multiply one of the above numbers by the number of days you use the appliance in a year.

A simple energy audit can be the first step towards greater efficiency and savings. It can be part of the decision-making process before weather-proofing your home, installing solar panels, buying energy efficient appliances or lightbulbs, and automating your thermostat. In addition to saving money and preparing for an outage, becoming aware of your energy use can also help you reduce your carbon emissions and become aware of the impact today’s choices have on future generations.


Photo by Alexander Dummer on Unsplash