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Home Energy · Audit

Standby Power Audit

See exactly what your always-on devices cost per year. Routers, set-top boxes, chargers and standby TVs collectively add €50–€250 to a typical European bill.

Always-on load

82 W

Annual energy

718 kWh

Annual cost

215

Annual CO₂

215 kg

Standby devices

DeviceWattsCountkWh/yrCostCO₂ kg
10531.5431.5
13139.4239.4
8826.2826.3
5315.7715.8
7923.6523.7
7021.0221
3510.5110.5
185.265.3
3510.5110.5
10531.5431.5

Formula

Annual kWh = watts × count × 24 h × 365 days ÷ 1000

Annual cost = kWh × tariff

Annual CO₂ = kWh × grid intensity

A €20 smart plug that cuts a 15 W standby cluster saves 131 kWh/year — €39 at €0.30/kWh, and 39 kg CO₂ on a 300 g CO₂/kWh grid. Payback under 7 months.

FAQ

How much does standby power cost per year?
Typical European household: 30–100 W of always-on load × 8,760 h/year = 260–870 kWh/year. At €0.30/kWh that is €80–260 per year for devices you are not actively using. In the US: €50–150 at ~€0.16/kWh.
What is a "vampire load"?
Any device drawing power while notionally off — TVs waiting for the remote signal, chargers plugged in without a phone, printers on standby, consoles in rest mode. The EU limit is 0.5 W for basic standby but many older devices predate it and pull 5–20 W each.
Are smart plugs worth it?
A €20 smart plug cutting 15 W of continuous draw saves 131 kWh/year ≈ €39. Payback is under 7 months at European tariffs. The environmental win is even larger on high-CO₂ grids (Poland, Germany) where each kWh avoids 400–660 g of CO₂.
What is the cheapest way to find vampire loads?
A €15 plug-in wattmeter (Kill-A-Watt, Belkin Conserve Insight, Voltcraft SEM 6000). Plug it between the wall and the suspect device, wait 24 hours, read the total kWh. Anything over 0.05 kWh in 24 hours is worth switching off at the plug.