CostRunningWhat Standby Power Really Costs
Standby is the most talked-about and least measured item on any electricity bill. Both halves of that are worth fixing.
The number that makes it make sense
One watt left on permanently is 8.76 kWh a year. At $0.17 that is $1.49; at £0.25, £2.19; at €0.35, €3.07 — every year, for as long as the device exists.
So the question for any device is not “does it use power on standby” but “how many watts”. One watt is a rounding error. Twenty watts is a fridge.
Where the watts actually are
| Device | Standby draw | A year at $0.17 |
|---|---|---|
| Set-top box or DVR | 15–30 W | $22–45 |
| Old AV receiver | 10–20 W | $15–30 |
| Games console, rest mode | 10–15 W | $15–22 |
| Second fridge, garage | (not standby — 500 kWh) | $85 |
| Desktop PC, left idle | 60–90 W | $89–134 |
| Soundbar | 3–5 W | $4–7 |
| Microwave clock | 2–3 W | $3–4 |
| Modern TV, true standby | under 1 W | under $1.50 |
| Phone charger, nothing attached | 0.3 W | $0.45 |
Two rows at the bottom are why the traditional advice is now mostly wrong. EU rules cap most standby modes at 0.5 W and similar limits apply elsewhere, so the chargers and clocks people were told to unplug are genuinely trivial today.
What is not trivial is anything that stays awake rather than asleep: a box waiting to record, a console waiting to download, a receiver waiting for a signal, a PC nobody put to sleep.
What to do, in order
- Find the boxes. Set-top box, DVR, console, receiver. Four devices usually account for most of a household’s standby.
- Use their own low-power modes. A console’s rest mode with automatic downloads switched off is a fraction of the same rest mode with them on.
- Switch off at the wall what you can reach. A plain switched extension lead behind the television handles the whole entertainment stack in one flick.
- Ignore the rest. Chargers, clocks and modern televisions are not worth the inconvenience.
How to measure it yourself
Two ways. A plug-in energy monitor on individual devices — though many cannot resolve loads under about 3 W, which is fine because those do not matter. Or a whole-house reading: late at night with everything obviously off, note the meter, wait an hour, note it again. The difference is your household’s baseline, standby included.
A typical result is 30 to 60 W, which is 260 to 525 kWh a year. Put your own figure into the standby power calculator and see what it is worth where you live.