Standby Power Cost
Calculate the cost of electronics left on standby all year.
About Standby Power Cost
Each device left plugged in draws a small standby current around the clock. Multiplying that draw across devices and a full year reveals the phantom load. A handful of watts per device is easy to ignore, but dozens of devices across a year make standby power a real and avoidable charge.
Formula
Standby Power Cost
Annual kWh = devices x standby watts x hours x 365 / 1000
- standby watts
- Average draw while not actively in use
Worked example
With the default values below, Standby Power Cost returns Annual Standby Energy of 240.9. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Number of devicesminimum 1
- 10
- Average standby wattsminimum 0 watts
- 3 watts
- Standby hours/dayminimum 0 hours
- 22 hours
- Electricity rateminimum 0 $/kWh
- 0.15 $/kWh
Results
- Annual Standby Energy
- 240.9 kWh
- Annual Cost
- $36.14
- Monthly Cost
- $3.01
Step by step
- 1Values used
- 2Standby Power Cost
- 3Annual Standby Energy= 240.9 kWh
- 4Annual Cost= 36.14
- 5Monthly Cost= 3.01
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Standby Power Cost calculated?
Annual kWh = devices x standby watts x hours x 365 / 1000 Each device left plugged in draws a small standby current around the clock. Multiplying that draw across devices and a full year reveals the phantom load.
Why does Standby Power Cost matter?
A handful of watts per device is easy to ignore, but dozens of devices across a year make standby power a real and avoidable charge.
What values do I need to enter?
This calculator takes 4 inputs: Number of devices, Average standby watts, Standby hours/day, Electricity rate. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.