A $20 smart plug. That's our entire energy monitoring infrastructure.
Current draw right now: < 30W
Annual cost: ~$42 (Italy, €0.25/kWh — we're getting robbed)
US equivalent: ~$18/year at average residential rates
What's running on those 30 watts:
- nginx + MariaDB + Docker
- Mail stack (Postfix + Dovecot)
- HAProxy + SSL termination
- Self-hosted analytics (GoAccess)
- DNS failover monitor
- IoT MQTT broker
- Backup server (283 snapshots)
- License server
- A Bitcoin miner (ESP32, won't make us rich, philosophically consistent)
- A phone charger (emergency 4G hotspot)
Hardware: Raspberry Pi 4B + two Orange Pi boards. All ARM. All containerized.
The numbers
~330 human visitors/day from < 30W.
We also get ~7,400 AI crawler hits/day (GPTBot, ClaudeBot, Perplexity, Googlebot...). That's a separate problem/opportunity depending on how you look at it.
vs AWS
Rough equivalent stack (t3.medium + RDS + SES + CloudWatch):
~$960/year.
We pay $42. Hardware amortized over 5 years adds ~$60/year.
$102/year total vs $960/year.
PageSpeed: 99/100 on mobile
Throttled 4G. Raspberry Pi.
Not because ARM is fast. Because if software works correctly under constraint, it works correctly anywhere. The constraint is the test, not the limit.
What the P110 actually measures
Real-time wattage. Daily/monthly kWh. Cost projection. Historical data.
We publish it live: stats.lake8.dev/geo.html — the ⚡ widget, updates every 5 minutes.
No estimates. No carbon credits. No 200-page sustainability report.
Just a number. Measured. Public.
One question for every SaaS vendor
How many watts does your software use per active customer?
Yeah, I know.
Signed by BASIC, our Lagotto Romagnolo and unofficial CEO 🐾
Live data: stats.lake8.dev/geo.html
Top comments (4)
"Because if software works correctly under constraint, it works correctly anywhere." — I want this framed.
My whole setup is an accidental experiment in that sentence. I'm not a developer (physical therapist who ended up building internal tools for my hospital with AI), and everything I've shipped runs on one consumer NAS that was already sitting in the office: PHP, MariaDB, nginx, a couple of Docker containers, ~660 staff using it daily. The marginal server bill for two dozen tools is approximately the electricity the NAS was going to burn anyway.
What surprised me is how much the constraint taught. With no autoscaling to hide behind, a slow query isn't a line on a cloud bill — it's a nurse waiting at a screen, and she will tell you about it. So you fix the query. The hardware being humble made the software honest.
Your watts-per-active-customer question is the first infrastructure metric that's ever made me feel guilty for not knowing my own number. The NAS is rated around 60W, which puts me somewhere near 0.1W per person served — but that's a spec sheet, not a measurement, and your post is exactly about that difference. Adding a power meter to the shopping list.
Also, signing off with the dog's name is the most trustworthy thing in the whole post.
"The hardware being humble made the software honest" — I'm stealing this.
And yes, add the power meter. The difference between a spec sheet and a measurement is exactly the whole point. 60W for 660 staff is already remarkable — 0.1W/person would put you well below us.
The nurse at the screen is the best feedback loop in existence. No Datadog alert ever matched it.
BASIC approves of this comment. 🐾
Fair trade — a sentence for a sentence. The wristband economy of ideas.
Power meter ordered. When I have an actual measured number instead of a spec sheet, I'll come back and post it here — worst case, you get to enjoy me discovering the NAS idles hungrier than its datasheet admits.
A BASIC approval is the highest form of code review. Give him a scratch from the other side of the planet. 🐾
Power meter ordered is the best possible response to this post. A spec sheet is a marketing document. A measured number is a fact. Looking forward to the update — especially if the NAS turns out to be hungrier than advertised. That's the most useful kind of discovery.
Scratch delivered. BASIC acknowledges from Bologna with the dignity appropriate to his role. 🐾 :-)