Diagnosis

Standby power is real, and it is not a quarter of your bill

You have read that standby power is 5–10% of a household bill, or a quarter, depending on the article. One watt left drawing costs a fixed and knowable amount per year. Let us just multiply.

Published August 28, 2026 · Figures recomputed at every build from public data

The only constant you need

$1.61per watt, per year

8,760 hours a year at 18.34¢ per kWh

Multiply any always-on wattage by this and you have its annual cost. No other arithmetic is required.

Adding up a realistic house

Not a worst case, and not a smug minimalist one. A normal home with a router, a couple of televisions, a games console, some smart speakers, a few cameras and the usual chargers.

At 18.34¢/kWh. Adjust for your own house with the calculator.
DeviceWattsHow manyA year
Wi-Fi router and modem12 W1$19
Set-top box or DVR15 W1$24
Games console in rest mode2 W1$3.21
Televisions on standby1 W2$3.21
Smart speakers3 W2$9.64
Security cameras5 W2$16
Microwave clock3 W1$4.82
Chargers left plugged in0.5 W4$3.21
Total52 W$84

Standby, appliance by appliance

The appliances on this site that draw something when they are not in use, and what that costs on its own — separately from the cost of using them.

At 18.34¢/kWh. “Share of its total” is how much of that appliance’s whole annual cost is spent doing nothing.
ApplianceStandby drawIdle hours a yearStandby a yearShare of its total
Laser printer6 W5,970$6.5767%
Garage door opener4 W8,753$6.4290%
Furnace blower / air handler8 W4,000$5.873%
Central air conditioner15 W1,800$4.951%
Microwave oven3 W8,669$4.7719%
Water softener3 W8,541$4.7075%
Espresso machine3 W8,030$4.4211%
Treadmill5 W4,650$4.2618%
AV receiver3 W7,665$4.2214%
Gaming PC3 W7,300$4.024%
Electric oven3 W6,900$3.806%
Robot vacuum3 W6,840$3.7659%
EV charging (Level 2 home)3 W6,711$3.691%
Heat pump (heating)12 W1,650$3.631%
Pool heat pump10 W1,920$3.521%
Massage chair4 W4,700$3.4548%
Coffee maker2 W8,651$3.1716%
Games console2 W7,665$2.817%
Golf cart charger5 W2,850$2.612%
Mini split (cooling)8 W1,680$2.462%
Welder15 W880$2.4214%
CPAP machine2 W6,205$2.2810%
Electric furnace10 W1,200$2.200%
Tanning bed5 W2,380$2.1812%
Sump pump2 W4,700$1.7211%
EV charging (Level 1 wall socket)2 W4,530$1.660%
Pool salt chlorinator3 W2,880$1.584%
3D printer3 W2,700$1.4913%
Desktop computer2 W4,000$1.474%
Electric cooktop1 W7,673$1.413%
Range hood1 W7,590$1.3913%
Toaster oven1 W7,050$1.295%
LED television1 W6,935$1.274%
OLED television1 W6,935$1.273%
Washing machine1 W6,900$1.277%
Electric clothes dryer1 W6,900$1.271%
Heat pump clothes dryer1 W6,720$1.232%
Dishwasher1 W6,600$1.213%
Air fryer1 W5,900$1.086%
Electric fireplace2 W2,660$0.981%
Laptop1 W4,800$0.884%
Robotic pool cleaner2 W2,365$0.879%
Central vacuum system2 W2,360$0.877%
Rice cooker1 W4,600$0.848%
Electric sauna heater2 W2,250$0.831%
Electric underfloor heating2 W2,240$0.821%
Projector1 W4,300$0.793%
Electric pressure cooker1 W3,488$0.648%
Grow light1 W2,920$0.540%
Ceiling fan1 W2,880$0.535%
Infrared heater1 W2,520$0.460%
Space heater1 W2,400$0.440%
Computer monitor0.5 W4,000$0.373%
E-scooter charger0.5 W4,000$0.373%
Bread maker1 W1,640$0.303%
Window air conditioner1 W1,540$0.280%
E-bike charger0.5 W3,000$0.282%
Portable air conditioner1 W1,400$0.260%
Sous vide circulator1 W1,200$0.224%
Humidifier1 W1,120$0.212%
Electric smoker1 W340$0.061%

Where the famous statistic comes from

Two things inflate it. The first is age: standby draw has collapsed since the studies that produced those figures, because regulation capped it and switch-mode power supplies got dramatically better. A set-top box that drew 25 W on standby in 2008 draws a few watts now, and a charger that drew 2 W drays a fraction of one.

The second is definitional. Many studies count “always-on load” rather than “standby”, and always-on load includes the refrigerator, the well pump, the security system and the network — devices that are doing their job, not idling. Counted that way the number is large, but almost none of it is waste you can switch off.

Why standby collapsed, and when

The figures in the famous statistic were largely gathered before three things happened, and each of them cut idle draw by a large factor.

  1. Linear power supplies were replaced by switch-mode ones. The old design used a mains-frequency transformer that drew magnetising current whenever it was plugged in, whether or not anything was attached — which is where the folklore about warm chargers wasting power comes from. It was true. It stopped being true.
  2. Standby was regulated. Voluntary programmes and then mandatory limits pushed idle draw for most consumer categories down to one or two watts, with sub-watt targets for external power supplies. A device sold today has a legal ceiling on the number the old studies measured.
  3. Displays and clocks moved to LED and low-power microcontrollers. A vacuum-fluorescent display drew several watts around the clock; the LED replacing it draws a fraction of one.
“Then” is the order of magnitude in the era the widely-quoted studies were run; “now” is typical of current equipment. Priced at 18.34¢/kWh.
DeviceThen, roughlyNow, roughlyDifference a year
Set-top box or DVR25 W5 W$32
Television on standby6 W0.5 W$8.84
Phone charger, nothing attached2 W0.1 W$3.05
Games console, rest mode20 W2 W$29

This is why the advice aged badly rather than being wrong when it was written. The people repeating it are quoting a real measurement of a world that no longer exists — and the one category where the old advice still holds is old equipment, which is exactly the thing sitting forgotten in a spare room.

The ones actually worth doing something about

  • A hot water recirculation pump on no timer. Around 40 W continuously, which is more than every charger in the house by a factor of twenty. Fit the timer it came with.
  • An old cable box or DVR. Frequently 15–30 W around the clock, and often serving a television nobody uses any more.
  • A second refrigerator. Not standby at all, but it belongs on any honest list of things quietly drawing power in a room you do not enter.
  • A games console kept network-connected in rest mode. Small individually, but it is a setting rather than a sacrifice.

The ones not worth doing anything about

Phone chargers. A modern one with nothing attached draws well under half a watt, so four of them left plugged in all year costs about $3.21. Unplugging them is a ritual, not a saving, and the advice persists mostly because it is easy to give.

Questions

Do smart plugs use power themselves?
Yes, typically 0.5–1 W each to keep their radio alive. Putting a smart plug on a device that draws 1 W of standby saves nothing at all. They earn their keep on things with a real load and a schedule — a towel rail, a treadmill, a dehumidifier — not on chargers.
Does a power strip switch actually cut the draw?
Yes, a genuine mechanical switch on a strip disconnects everything downstream and takes the draw to zero. That is the one thing that reliably works, and it works because it is a switch and not a mode.
What about the refrigerator — should I count it?
Count it, but not as standby. It runs continuously because that is its job, and the way to reduce it is a better seal, clean coils or a newer unit, not a switch.

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