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marcus_cemestoday at 10:24 AM1 replyview on HN

Small anecdote on the mobile/robotics part, two years ago I was tasked with a small research sensor/timelapse platform. I reached out for the Pi Zero 2 W, the new Pi camera, and the largest USB battery I could buy. Perhaps I had unrealistic expectations, but I was surprised how much power it draws, even at idle. The napkin math said about 6 days (0.5 W idle, 2 W loaded), in reality it was only 1-2 days.

In comparison, my older laptop idles at around 5 W, even with multiple applications open. Similar experience more recently when looking at setting up a small home lab, the new Pi 5 seems to idle at around 5 W. A friend told me he has an Intel-based mini PC that draws less power. I'm tempted to try re-purposing an old phone, that should in theory do better.


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walrus01today at 10:42 AM

This is AC wall power as measured by a kill-a-watt, I have an Intel N150 mini PC here with 12GB of RAM, 512GB cheap NVME SSD, with wifi active, it's 8.2W idle at an xfce4 desktop with a lighted keyboard and mouse attached to it. It came with a 110-240 to 19VDC 3A power supply.

I'd say the cheap ac to dc power supply it came with is no more than 80% efficient so 6.56W DC would be what I might expect to see if I peeled apart its DC feed side power cable and put a precise clamp ammeter around it.

Absolutely maxed out with stress-ng it's 24.6W at the wall.

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