Standby Power Calculator
Price always on vampire loads per year and month.
What it does
Vampire loads never sleep so you can. Routers, boxes, consoles, chargers, and smart speakers sip watts all night to keep clocks lit and remotes ready. One device means little; a house of them means a visible line on the bill.
The tool above prices that line. Enter steady watts, hours per day, and your rate to get yearly kWh with yearly and monthly cost. Defaults describe a 50 W always on corner at $0.17, so the page opens solved at 438 kWh, $74.46 a year, and $6.21 a month.
Scale cuts both ways. A 100 W corner doubles everything to 876 kWh and $148.92, while a lone 5 W TV standby sips 43.8 kWh for $7.45. Small loads earn their hunt on fleets: ten forgotten 5 W bricks equal the example corner.
Measurement beats nameplates. Bricks and boxes draw less than their labels most hours, so a plug meter for a week pays for itself in honest watts. Power strips and switched outlets then convert knowledge into savings without daily discipline.
Use the table for common household corners, then run your loads. The page prices steady draw only; fridges, heaters, and washers cycle on thermostats and need metered profiles. Within range it answers the bill question fast: what the silent watts cost per year.
How to use
- Enter steady watts (plug meter beats nameplate).
- Enter hours per day.
- Enter dollars per kWh.
- Read yearly kWh first.
- Read yearly and monthly cost.
- Hunt the biggest 24 h loads first.
Formula
- Watts
- Steady draw in watts.
- Hours
- Daily run time, 24 for always on.
- Rate
- Your electricity price.
Hours cap at 24 per day and the rate is dollars per kWh you enter. Monthly cost divides the yearly figure by 12. The page prices steady loads only; cycling appliances with thermostats need metered profiles instead.
Worked example
Example: 50 W around the clock
A 50 W always on corner (router, box, chargers) runs 24 h at $0.17 per kWh. Find the yearly damage.
- Yearly energy = 50 x 24 x 365 / 1000 = 438 kWh.
- Yearly cost = 438 x 0.17 = $74.46.
- Monthly = 74.46 / 12 = $6.21.
- A 100 W corner wastes 876 kWh and $148.92.
- A 5 W TV standby sips 43.8 kWh and $7.45.
- Switches and strips beat standby.
Reference table
| Corner | Yearly kWh | Yearly cost |
|---|---|---|
| 5 W TV standby | 43.8 kWh | $7.45 |
| 20 W network gear | 175.2 kWh | $29.78 |
| 50 W media corner | 438 kWh | $74.46 |
| 100 W office corner | 876 kWh | $148.92 |
Limits
- Steady loads only; no cycling appliances.
- Your rate and hours assumed exact.
- One load per run; add corners yourself.
- No demand charges or time of use bands.
Common mistakes
- Using nameplate instead of metered watts.
- Pricing 24 h for a night only load.
- Forgetting the rate decimals.
- Chasing one phone brick, missing the theater.
- Ignoring strips after measuring.
Try it yourself
Quick checks. Answers sit tucked under each question.
100 W around the clock?
876 kWh. Cost $148.92. Monthly $12.41.
5 W TV standby around the clock?
43.8 kWh. Cost $7.45. Monthly $0.62.
10 W all day? Work it by hand.
10 x 24 x 365/1000 = 87.6 kWh. Cost 87.6 x 0.17 = $14.89. Monthly $1.24.
Questions
What is standby power?
Electricity devices sip when off but plugged in. It keeps clocks, remotes, and network links alive around the clock.
How is yearly kWh found?
Watts times hours times 365 divided by 1000. The example: 50 x 24 x 365/1000 = 438 kWh.
How is the cost found?
kWh times your rate. At $0.17 the example costs $74.46 a year, about $6.21 a month.
Does it know my rate?
No. Rates, hours, and device mixes vary; the tool trusts your three inputs and prices them exactly.
Is a 5 W load worth chasing?
Yes. A 5 W standby at 24 h costs $7.45 a year, so small loads still deserve switches on big fleets.
Does it cover the whole bill?
No. Heating, cooling, and duty cycled appliances need their own metered math.