How much does it cost to run a 100 W home server 24/7? NAS energy guide
A 100 W home server or NAS running 24/7 at 80% load costs about $157.68 a year to power at $0.18/kWh, $13.14 a month. That works out to 876 kWh annually for a machine that's doing something useful every hour of the year: file serving, Plex, backups, Home Assistant, or a dev box.
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How this is calculated
The big difference from a gaming PC isn't peak power. It's the "24/7" multiplier. A 100 W always-on device uses as much annual electricity as an 850 W gaming PC running 4 hours a day, because 24/7 × 100 W still beats 4 × 850 W × 80%. That's why hobbyists obsess over efficient Mini PCs, Synology units, and Raspberry Pi-class servers: the watts matter in a way that doesn't apply to desktops that shut down at night.
Verdict
$158 a year is the mental benchmark for "is self-hosting worth it?" It's below the cost of most paid cloud equivalents but it's not free. If your server idles at 30 W instead of drawing 80% of 100 W, you can halve the bill.
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Frequently asked questions
Is it cheaper to run a home server or pay for cloud storage?
How do hard drives affect home server power draw?
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