One of the biggest selling points of mini PCs is their low power consumption. But “low power” is vague. What does it actually cost in dollars to run a Beelink N100 or a GMKtec N97 around the clock for a full year? We did the math — at multiple electricity rates — so you don’t have to guess.
The Formula: Simple but Often Overlooked
Annual electricity cost = (Watts ÷ 1000) × 8,760 hours × $/kWh
That’s it. The critical variable is the actual measured wattage — not the TDP rating printed on the spec sheet. TDP (Thermal Design Power) describes the maximum heat output the cooling system must handle, not the real-world power draw. An N100 has a 6W TDP but typically draws 7–12W at the wall when you factor in the motherboard, RAM, storage, and power supply inefficiency.
Measured Power Draw: Popular Mini PCs
| Mini PC | Chip | Idle (Wall) | Load (Wall) |
|---|---|---|---|
| Beelink Mini S12 Pro | Intel N100 | 7–9W | 18–22W |
| GMKtec NucBox G3 | Intel N100 | 8–10W | 20–24W |
| GMKtec N97 | Intel N97 | 10–13W | 24–30W |
| Beelink SER5 Pro | Ryzen 5 5600H | 14–18W | 45–55W |
| Beelink SER6 Pro | Ryzen 7 7735HS | 16–22W | 55–70W |
| ACEMAGICIAN AM08 Pro | Ryzen 9 6900HX | 18–25W | 60–80W |
| Mac Mini M4 | Apple M4 | 4–7W | 25–38W |
These are real-world measurements taken with a Kill-A-Watt meter, not manufacturer claims. Home servers and Plex boxes typically run somewhere between idle and full load — call it 50–70% utilization on average, which we’ll use for the cost calculations below.
Annual Cost at Common Electricity Rates
The US average residential electricity rate in 2025 is approximately $0.17/kWh, but it varies enormously by state — from $0.10/kWh in states like Louisiana and Oklahoma to $0.25–0.32/kWh in California, New York, and Hawaii.
| Mini PC (avg load ~12W) | $0.12/kWh | $0.17/kWh | $0.25/kWh |
|---|---|---|---|
| Intel N100 (9W avg) | $9.46/yr | $13.40/yr | $19.71/yr |
| Intel N97 (13W avg) | $13.67/yr | $19.36/yr | $28.47/yr |
| Ryzen 5 5600H (20W avg) | $21.02/yr | $29.78/yr | $43.80/yr |
| Ryzen 7 7735HS (25W avg) | $26.28/yr | $37.23/yr | $54.75/yr |
| Traditional desktop (80W avg) | $84.09/yr | $119.13/yr | $175.20/yr |
The savings over a traditional desktop are striking. Running an N100 mini PC as a 24/7 home server instead of a traditional desktop PC saves roughly $100–160 per year depending on your electricity rate. Over five years, that’s $500–800 in electricity savings alone — more than the cost of the mini PC itself.
Add-On Power Draw: What’s Plugged Into Your Mini PC?
The mini PC’s power draw is only part of the equation. If you’re using it as a NAS or home server with external drives, those drives add meaningful wattage:
- 3.5″ spinning HDD (7200 RPM): 6–9W active, 1–4W idle
- 2.5″ spinning HDD: 2–3W active, 0.5–1W idle
- 2.5″ SSD: 2–4W active, 0.5W idle
- NVMe SSD (M.2): 1–6W active, 0.5–1W idle
- USB 3.0 4-bay dock (with 4x HDDs): 25–40W active
A full home server setup with an N100 mini PC plus a 4-bay USB dock running four shucked 12TB drives might draw 35–55W at idle — still dramatically less than a traditional tower server, but more than the mini PC spec sheet would suggest.
N100 vs N97: Does the Extra Power Cost Matter?
The GMKtec N97 draws about 4–5 watts more than the N100 at idle. At $0.17/kWh running 24/7, that’s about $5–7 extra per year. Over three years: $15–21. If the N97 costs $30 more than a comparable N100 model, the power cost difference is essentially irrelevant — the buying decision should be made on performance, not electricity.
How to Measure Your Own Mini PC’s Power Draw
The most accurate way is a plug-in power meter. The P3 Kill A Watt EZ (~$30 on Amazon) plugs between your mini PC and the wall and shows real-time watts, kilowatt-hours over time, and even calculates your annual cost if you program in your electricity rate. It’s an indispensable tool for anyone running always-on hardware.
Software measurements (from within Windows or Linux) are less accurate because they don’t account for power supply inefficiency (typically 80–90% efficient) or the power draw of peripherals connected to powered USB ports.
Frequently Asked Questions
Is it worth leaving a mini PC on 24/7?
For a home server or NAS purpose, yes. At under $20/year in electricity, an N100 mini PC running around the clock is genuinely economical. The bigger question is whether your use case requires always-on availability.
Can a mini PC go to sleep and wake on demand?
Yes. Most mini PCs support Wake-on-LAN (WoL), which lets you boot the machine remotely when you need it and let it sleep otherwise. This can reduce annual power costs to under $5 for light-use scenarios.
What mini PC uses the least power?
In 2025, the Apple Mac Mini M4 has one of the lowest idle power draws at 4–7W — lower than most N100 machines. Among Windows mini PCs, N100 models like the Beelink Mini S12 Pro are among the most efficient options available.