Homelab Operator

Power cost for homelab operators: what your 24/7 server actually costs

Last updated 2026-06-24

Calculate yearly cost as watts x 8.76 x your kWh rate. A 100W server at $0.30/kWh costs $263/year. Measure idle power separately, because that's where most servers spend their time.

Daily Cost

$0.72

2.4 kWh / day

Monthly Cost

$21.90

73 kWh / month

Yearly Cost

$262.80

876 kWh / year

A 100 W always-on server at $0.30/kWh, pre-loaded. Set utilization to 80% or drop the rate to $0.12/kWh to see the real idle-vs-peak split.

Edit in the full tool

Homelab operators can underestimate the yearly electricity cost of a 24/7 server. A 100W home NAS at $0.30/kWh costs $263 per year. A 300W rack server at the same rate costs $788. A 500W GPU rig costs $1,314. Dollar figures here use $0.30/kWh as a round example rate in US dollars, and the calculator can switch to your own rate, your country's average, another currency, or time of use rates.

Why this matters for you

The formula is simple: watts x hours x 365 / 1000 x rate. A 100W device running 24/7 consumes 876 kWh per year. At $0.30/kWh, that's $263. At $0.12/kWh, it's $105. The biggest lever is idle power: a server that idles at 80W and peaks at 300W averages about 124W if it's idle 80% of the time, not 300W. Measure with a wall-socket power meter before estimating.

Average the day, not the peak

Most homelab gear spends its day near idle. Say a server idles at 40 W for 20 hours and works at 150 W for 4 hours. Its daily average is about 58 W, which comes to 511 kWh a year, or about $153 at $0.30/kWh. Using the 150 W peak for all 24 hours would overstate the bill by more than 2.5 times.

Measure at the wall

A plug-in power meter shows what you actually pay for, including power supply losses, fans and drives. Software readings like CPU package power leave those out and read low. Plug the whole setup into the meter, switch, router and UPS included, and let it run for a few days to catch both quiet and busy periods.

Small loads add up

Every watt that runs all year uses 8.76 kWh. Four hard drives that draw 5 W each add 20 W, about 175 kWh and $53 a year at $0.30/kWh. A small board computer that averages 5 W costs about $13 a year at the same rate. Count these loads before you blame the server itself.

Verdict

Average the idle and busy hours instead of using the peak, and measure at the wall with a power meter. Then multiply watts by 8.76 and your kWh rate for the yearly cost.

Open the Power Cost Estimator

Frequently asked questions

Is it worth replacing an old server to save power?

Work out the yearly saving and compare it with the price. Cutting average draw from 120 W to 30 W saves 788 kWh a year, about $237 at $0.30/kWh. A $400 replacement would pay for itself in about 1.7 years.

Which electricity rate should I use?

Use the price per kWh on your bill, including any taxes and fees charged per kWh. Leave out fixed daily or monthly charges, since running a server doesn't change them. On time of use pricing, add each period's price and hours in the calculator, and it works out the average for the hours the server runs.

How much does a Raspberry Pi cost to run 24/7?

A board that averages 5 W uses 43.8 kWh a year, about $13 at $0.30/kWh. Add the draw of any attached drives, and measure your own board at the wall to get its real average.