Comment by nunobrito | Hacker News Reader

Comment by nunobrito | Hacker News Reader

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Compared to other microcontrollers: ESP32 is very power hungry. Shiny displays are very power hungry, Wi-Fi is power hungry. So expect to draw about 5 watts/hour continuously while in operation with all bells and whistles.

With this said (I'm also using them for off-grid) you will need to put them to sleep and only use the display when absolutely needed for most scenarios. I've recently started using devices with e-paper display which at least solve that nuisance of the display power draw: https://www.waveshare.com/wiki/ESP32-S3-ePaper-1.54

The last thing to keep in mind is heating. They will warm quite a bit and you should consider a way to either keep them cooled or make them sleep enough to cooldown, otherwise they will reboot or stop working until they are cooled again.

Depends... do you need wifi, screen and others always on? can you wake some on a timer? on user interaction? on interrupts?

https://lastminuteengineers.com/esp32-sleep-modes-power-cons...

You can use those sleep modes in micropython as well

https://randomnerdtutorials.com/micropython-esp32-deep-sleep...

> 5 watts/hour

Typo I'm guessing, but I found this unit of "energy acceleration" amusing.

"Gotta go fast" :-)

In my language we say it colloquially that way, turned out wrong in English. Should have been 5 Wh.

Rather you would say it draws 5 watts. If someone is interested in draw over a period, e.g. over one hour, you'd say it used 5Wh in that period.

> If someone is interested in draw over a period, e.g. over one hour, you'd say it used 5Wh in that period.

Wh per hr? Let's just cut through the confusion and say it draws (J/s)Hr / Hr. :P

More seriously, if you are interested in energy the "correct" SI unit is J although in electrical applications [k/Mega/Giga]Whr is common. If you are interested in energy draw over a period, aka power, the "correct" and common unit is W. While 5 Wh per hour might seem simpler, it is equivalent to say this thing draws as much energy per hour as a device that that draws 5W would draw over one hour - needlessly redundant.

In the offgrid world we look constantly at batteries and they often express themselves in Wh. So it is a habit to measure anything else that way to avoid confusions.

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