Appliance Energy Cost Calculator
What each appliance really costs you per year, ranked — and why phantom load is a fraction of what the folklore claims.
Heating & water
Laundry & kitchen
Always running
Lighting
Electronics
Always on
True standby
| Appliance | kWh/yr | Cost/yr | Share |
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Phantom load is much smaller than you have been told
The advice to unplug chargers dates from an era when a phone charger idled at one or two watts. Regulation has since capped most standby at half a watt — and half a watt is 4.4 kWh a year, about seventy pence. Unplugging every charger in a house is worth a few pounds annually. It is not where anybody's money goes.
What is worth finding is the handful of always-on things that are actually doing something: a cable box or DVR at 25 W costs around $37 a year on its own, more than every phone charger in the house combined. Those are not standby loads in any meaningful sense — they are appliances running quietly.
- The big savings are almost never in electronics. Heating, cooling, water heating and drying dominate an electricity bill so completely that half a degree on the thermostat is worth more than every plug in the house.
- One watt continuous is 8.76 kWh a year. That single conversion is most of what anybody needs to reason about standby power, and it makes the arithmetic obvious without a calculator.
- Cycling appliances are quoted at equivalent full-power hours. A fridge draws 150 W but runs about a third of the time, so it appears as 8.4 hours a day rather than 24. Using 24 would treble its cost — a common way these estimates go wrong.
- Age matters more than habits for some appliances. A 1990s refrigerator uses nearly three times a modern one, and a house still on incandescent bulbs spends eight times what an LED house does on lighting. Neither is fixable by unplugging anything.
- These are typical figures, not measurements. A plug-in energy meter costs very little and settles the question for whichever appliance you actually suspect — which beats any table, including this one.
How to use
- Set your electricity rate — it is on the bill, per kilowatt-hour.
- Tick the appliances you have.
- Read the ranked list; the order is rarely what people expect.
- Compare the standby total against the biggest single line.
Frequently asked questions
Is it worth unplugging chargers and appliances on standby?
Far less than you have probably been told. The advice dates from an era when a phone charger idled at one or two watts, and regulation has since capped most standby at half a watt. Half a watt is 4.4 kilowatt-hours a year, which is well under a pound. Unplugging every charger in a typical house saves a few pounds annually, and the effort is better spent almost anywhere else.
So what should I unplug?
The handful of always-on things that are actually doing something rather than merely waiting. A cable box or DVR draws 20 to 30 watts continuously and costs around 37 dollars a year on its own — more than every phone charger in the house combined. Games consoles left in instant-on mode, old set-top boxes and some smart speakers are the same story. Those are not standby loads in any useful sense; they are appliances running quietly.
Where does my electricity actually go?
Heating, cooling, water heating and drying, in almost every home that uses electricity for them. An electric water heater alone runs to around 4,400 kilowatt-hours a year, which typically dwarfs everything else on the list put together. That is why half a degree on the thermostat or a shorter shower routine is worth more than every plug in the house, and why hunting phantom loads is looking in the wrong place.
How do I convert watts into an annual cost quickly?
One watt drawn continuously is 8.76 kilowatt-hours a year, because there are 8,760 hours in one. So a 25 watt cable box is 219 kilowatt-hours, and at 17 cents that is about 37 dollars. That single conversion makes standby power intelligible without a calculator, and it is the reason a half-watt charger is not worth crossing a room for.
Why does the fridge show fewer than 24 hours a day?
Because a fridge cycles. It draws roughly 150 watts while the compressor runs and sits idle the rest of the time, averaging about a third duty. This tool quotes equivalent full-power hours, so a fridge appears as 8.4 hours a day rather than 24. Multiplying the running wattage by 24 would treble the answer, and it is one of the commonest ways these estimates go badly wrong.
Does the age of an appliance matter much?
For some, enormously. A refrigerator from the 1990s uses close to three times what a modern one does, and a house still lit by incandescent bulbs spends around eight times what an equivalent LED house spends on lighting. Neither of those is fixable by changing habits — they are replacement decisions, and they are usually far larger than any behavioural saving available.
How accurate are these figures?
They are typical values rather than measurements, and the spread between individual units is wide. A heat pump varies with outdoor temperature by more than any single number can capture, and two fridges of the same size can differ by a factor of two. A plug-in energy meter costs very little and settles the question definitively for whichever appliance you actually suspect, which beats any table including this one.
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