Standby power: the cost of "off"
Devices that are switched off but plugged in still draw power — keeping a clock alive, listening for a remote, staying ready to wake instantly. One device is pennies. A house full of them, running all 8,760 hours of the year, is a line on the bill.
The arithmetic is unforgiving because the hours are maximal: every standby watt costs 8.76 kWh a year — about $1.49 per watt at the $0.17/kWh example rate. A DVR box idling at 25 W uses roughly 219 kWh and $37.23 a year before it records a single show.
The $0.17/kWh default is a rough example rate — about the US residential average on EIA figures, and it moves over time. Type in the rate from your own electricity bill for numbers that mean anything for your home. Standby figures are typical values reported for each device class, not measurements of any specific model — your unit may sit above or below its row. A plug-in energy monitor settles it for the exact device in your wall.
Typical standby draws and what they cost per year
| Device (off / idle, plugged in) | Standby watts | kWh / year | Cost / year | Note |
|---|---|---|---|---|
| Cable / satellite DVR box | 25 | 219 | $37.23 | DVR boxes are the classic vampire load — many draw near full power around the clock. |
| Game console (rest / standby mode) | 7 | 61.3 | $10.42 | Instant-on modes cost more; fully off or eco standby is usually under 1 W. |
| AV receiver (standby) | 6 | 52.6 | $8.94 | Network-standby features can push this much higher. |
| TV (standby) | 5 | 43.8 | $7.45 | Newer sets are often 0.5–1 W; older and larger sets run higher. |
| Desktop computer (asleep) | 4 | 35.0 | $5.96 | Sleep, not shut down. A full shutdown usually drops below 1 W. |
| Garage door opener | 4 | 35.0 | $5.96 | The receiver listens for the remote all day. |
| Printer (idle) | 4 | 35.0 | $5.96 | Inkjet printers idle low; laser printers vary more. |
| Microwave (clock display) | 3 | 26.3 | $4.47 | The clock and keypad stay live 24/7. |
| Streaming stick (idle) | 3 | 26.3 | $4.47 | Often powered from the TV’s USB port, so it sleeps with the TV — or not. |
| Coffee maker (clock / warm plate off) | 2 | 17.5 | $2.98 | Machines with a clock or touch panel. |
| Phone charger (plugged in, no phone) | 0.3 | 2.63 | $0.45 | Tiny on its own — the point is how many chargers a home leaves in. |
| One of everything above | 63.3 | 555 | $94.27 | An illustrative basket, not a typical home — most homes have several of some and none of others. |
Work out your own standby load
40 W is a plausible total for a home with a DVR box, a console in instant-on mode, a TV, a printer and a handful of chargers — adjust to your own count.
What is actually worth switching off
Rank by watts, not by guilt. The DVR/cable box and anything with an instant-on mode are the only common devices whose standby rivals a small appliance in use; a power strip with a switch, or the box's own eco setting, pays for itself quickly there. Game consoles belong in energy-saving shutdown rather than rest mode if they sit idle for days. At the bottom of the table, a phone charger's 0.3 W costs about $0.45 a year — unplug it for tidiness if you like, but the honest maths says your attention is worth more on the top three rows.
Two cautions. Some devices earn their standby: a DVR that must wake to record, a router everything depends on (and a router is "on", not standby — its draw belongs in the whole-home list). And some cheap power strips are worse than the problem — use a decent switched strip or a smart plug rated for the load, especially anywhere near heating appliances, which should never be switched by a timer strip at all.
Questions
- How much of a typical home's electricity is standby?
- Studies of US homes commonly put standby and always-on loads in the region of 5–10% of residential electricity — but the spread between homes is wide, driven mostly by a few big always-on devices rather than dozens of tiny ones.
- Do new appliances really draw less on standby?
- Generally yes. Standby limits in the US and EU have pushed plain "off" draw toward 0.5 W for many products. The exceptions are devices with network wake features, displays or DVR functions, which are allowed — and tend — to draw more.
- Will a smart plug tell me the real numbers?
- A smart plug or plug-in meter with energy monitoring will measure your exact device over a day or a week — far better than any table, this one included. Measure for a full day: some devices wake periodically and a five-minute reading misses it.
- Is standby the same as an appliance just being left on?
- Not quite. Standby is the draw in the "off but ready" state. A TV left on showing a picture is in use — that belongs in the main calculator at its running wattage, where an hour a day forgotten adds up much faster than its standby ever will.