The energy we use is usually measured in kilowatt-hours (kWh); 1 kWh is equal to 1,000 watts working for one hour.
In 2022, the United States consumed 4 trillion kilowatt-hours (kWh) of electricity. And of that 4 trillion kWh, 1.42 trillion were used in households. That's almost 40 percent of U.S. electricity going to power homes, which is more than either the commercial or the industrial sector uses.
Why the huge glut of energy consumption in the residential sector? Simple: Home appliances draw extreme amounts of energy. An appliance rated at 1,000 watts, left on for one hour, will use 1 kWh of electricity. So, what uses the most electricity in a home?
Accounting for 4.4 percent of residential energy usage, lighting is the fifth biggest source of home energy consumption. The good news? New LED light bulbs use significantly less energy than incandescent bulbs and even CFL bulbs.
Swapping incandescent bulbs for more energy-efficient LED bulbs is one way to save money on energy bills and reduce your home's energy consumption. Instead of leaving your outdoor security lights on all night, use motion-detecting lights.
Putting light bulbs on a timer can also ensure you don't accidentally leave lights on when you don't need them.
4. Refrigerators and Freezers
Refrigerators use the most energy of any kitchen appliance. How much energy your fridge uses, however, depends on your particular model. In 2023, Energy Star-certified refrigerators ranged in consumption from 88 kWh/year for a mini fridge to 807 kWh/year for a 31-cubic-foot (0.88 cubic-meter) smart fridge.
That's the thing about energy ratings for any particular appliance: The range is vast. Some people still have fridges from the 1980s (or even earlier), which means they're still using in the thousands of kWh every year (and enduring a commensurate electricity bill).
If you have a brand new, high-efficiency unit, your electricity usage could be more like 400 kWh/year. And then there are all the other factors: model size, freezer orientation (top freezers are more efficient), temperature settings, device placement, refrigeration habits and any available energy-saving modes (more on these in a moment).
Regardless of which model you have, there are steps you can take to reduce its energy use (although if your refrigerator/freezer is more than 15 years old, the most important change is to buy a new, energy-efficient model if you can afford it):
Check for a power-saver switch. Some refrigerators have in-door heaters to reduce external condensation. If you see a "power saver" switch, turn it on. If you don't notice condensation afterward, you don't need to use that feature.
Check the thermostat. For refrigerators, 40 degrees Fahrenheit (4 degrees Celsius) is ideal; for freezers, it's 0 degrees Fahrenheit (-18 degrees Celsius).
Defrost. More than 0.25 inch (0.64 cm) of frost buildup hurts efficiency.
Check the seals. Close the door on a piece of paper. It should be held firmly in place. If not, replace the seal.
Use good refrigeration habits. Label food so you can quickly find what you're looking for, cool hot food before refrigerating or freezing it and know what you want before you open the door.
3. Water Heating
According to the U.S. Department of Energy, heating water was responsible for 11 percent of U.S. home energy use in 2020. We use the water heater in so many applications: showers, cleaning dishes, cleaning clothes — it's a pretty ubiquitous part of our daily routine.
And at an average consumption of 400 kWh per month, it's also a power-intensive one.
Of course, the actual amount of energy you spend on hot water depends on a lot of factors, including the type (standard, solar, tankless) and size of your water heater, what temperature it's set at, how long you shower for and whether you wash your clothes in cold or hot water. But no matter what model you have, you can do a few things to help your water heater perform more efficiently:
Check the thermostat. You probably don't need your water hotter than 120 degrees F (50 degrees C).
Insulate the hot water storage tank and first 6 feet (1.8 meters) of pipes connected to the tank, so you're not losing heat during storage and transport.
Remove a quart of water every three months to limit sediment buildup that can lower the unit's efficiency.
Install a drain-water heat recovery system to capture the energy in used water.
Take shorter showers.
Wash clothes in cold or cool water.
Turn off the "water heat" feature on the dishwasher.
2. Space Heating
A home heating system is one of hungriest home appliances. It's also arguably the most necessary one.
The kWh range for heating devices is extremely broad, running from a measly 100 kWh per month to a shocking 3,500 kWh/month (if you live in a cold region, you've probably been shocked by your energy bill more than once). It all depends on which type of heat you use and how energy-efficient your particular model is.
Here are some approximate numbers for various heating systems:
Baseboard unit: 100-500 kWh/month
Portable heater: 200-300 kWh/month
Heat pump: 900-2,000 kWh/month
Electric furnace: 1,500-3,500 kWh/month
Other factors include where you set the thermostat and whether you have a programmable thermostat to cut back on wasted heat.
Upgrading to a more efficient heating unit is the best way to reduce your heat-related energy use — there are furnaces out there that operate at 97 percent efficiency, while your model may only be 78 percent efficient.
Short of an expensive upgrade, you can also help your system work more efficiently and lower your kWh if you:
Upgrade to a programmable thermostat.
Make sure the thermostat isn't located near any sources of heat or cold that might mess with its reading.
Set the thermostat to the lowest temperature at which you're comfortable.
Seal and insulate your home's ducts.
Make sure nothing is blocking your vents.
Replace your filters regularly.
And perhaps the best new habit to embrace: If you're feeling a bit cold, put on a sweatshirt.
1. Air Conditioning
In 2020, almost 88 percent of homes in the United States used air conditioning [source: EIA]. Air conditioning, which typically uses high-watt machines for extended periods of time, accounts for a big chunk of residential energy use.
As usual, the actual number of watts consumed in cooling a home varies greatly depending on the type of unit, the capacity, the time it's operating and the efficiency rating. An air-conditioning unit might use anywhere from 200 to 1,800 kWh/month.
You can take some important steps to improve the efficiency of an air conditioner, including:
Have a pro check the unit every year. Proper fluid levels, coolant charge and insulation are crucial to keep the device working efficiently.
Close the vents in rooms you hardly ever use.
Upgrade to a timed thermostat that will automatically switch off the AC as the temperature outside gets cooler.
Make sure you have at least 16 inches (41 centimeters) of insulation in your attic. This will keep more of the sun's heat out of your living space so the AC doesn't have to work as hard.
You can also upgrade to a more efficient model or, on the other end of the spectrum, decide a little sweat might not be so bad for you after all.
How to Calculate Energy Usage
Determine how many kWh per day an appliance uses with this formula:
Wattage × Hours Used Per Day ÷ 1,000
You can find the wattage on the nameplate.
Or, just buy a watt meter like Kill A Watt.
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Original article: What Uses the Most Electricity in a Home?
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