How much does it cost to run a 100 W home server 24/7? NAS energy guide
$126 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.
A 100 W home server or NAS running 24/7 at 80% load costs about $126.14 a year to power at $0.18/kWh, $10.51 a month. That works out to roughly 701 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.
By TechCompare · Updated
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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. An always-on 100 W device burns almost as much annual electricity as an 850 W gaming PC running 4 hours a day (about 701 kWh versus 993 kWh), because 24 × 100 × 0.8 nearly matches 4 × 850 × 0.8. 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
The arithmetic: 100 W at 80% utilization for 24 hours daily at $0.18/kWh consumes 700.8 kWh annually and costs $126.14 ($10.51 monthly). The 24/7 multiplier is what separates this from a gaming PC: 100 W always-on comes within 30% of the annual electricity an 850 W gaming rig burns in 4 hours a day, because 24 × 100 W × 0.8 nearly matches 4 × 850 W × 0.8. That's why homelab hobbyists obsess over idle-efficient hardware like Intel N100/N300 Mini PCs, Synology appliances that idle at 32 W with two spinning drives, and Raspberry Pi 5 setups at 5-8 W. Dropping the idle draw to 30 W halves the bill even at the same workload. That's the mental benchmark for "is self-hosting worth it": it's below the cost of most paid cloud equivalents and not free.
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