Energy & money
Where does your electricity actually go?
The three biggest slices of a home electricity bill, and the cheapest way to find your own.
Updated 4 October 2026
The big three
In US homes, the largest single use of electricity is air conditioning at 19%, followed by space heating and water heating at 12% each. Lighting and fridges come next.
Your home will be different: climate, heating fuel and appliances change the mix a lot. That is why the next step matters more than the averages.
Note: Figures are US averages from the EIA 2020 home energy survey. UK homes heated by gas will see a much smaller heating share on the electricity bill.
Measure one thing first
An energy-monitoring smart plug shows what a single appliance really uses. Leave it on one suspect for a week, note the kWh, then move it to the next.
Multiply the weekly kWh by your unit rate and by 52 for a rough yearly cost.
Safety: Check the plug's maximum load before using it with a heater or anything that draws a lot of power.
Then let the house do the remembering
- When everyone has left home: heating to eco, measured plugs off.
- Never switch off a fridge or freezer plug in an automation.
- Works in Home Assistant, Google Home, Alexa and Apple Home.
Sources
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