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Neat! Does it really not have any battery at all?

I would suspect that adding a battery would allow to support higher current spikes, which might enable it to drive a bigger display.

Just a capacitor should do for that purpose?

Also since this is e-paper, maybe you can just update the display incrementally.

It has a supercap and a 2032. Look at the AEM10941.

According to the schematic at at least. There is something that kinda looks like a battery in the images.

i already made a paper display using a wemos pico (has battery, charging and indicator) but this is very cool!

have to charge mine every few months but also display a lot more information

Do you have any blog post, video or anything that shows how to build your project?
unfortunately no, but hardware wise a exact copy of this: https://github.com/lmarzen/esp32-weather-epd

except for the wemos lolin c3 pico, very tiny esp

I have a couple of lolin boads as well I am using for development. The firebeetle board that is linked is hands down the best esp32 board due to the voltage regulator.

In hibernation with only the RTC clock running I believe it only consumes 0.008mA which is coin cell worthy with a < 1% duty cycle. With the wemos boards my lowest is around 3-4mA which is still fine but considering price is the same I would recommend the firebeetle ones.

oh, and the data i display on mine gets fetched from my homeassistant
Quick question: where are people sourcing their e paper displays? Everytime I think of picking some up I always feel either I'm paying too much or getting too little guarantees.
personally, Digikey/Mouser if I'm scoping and need to know a specific stock count ahead of time, paying the premium for some future-proofing makes sense to me in that regard

for prototypes/one-offs, aliexpress or ebay are fun if you ever only need one (haven't had a DOA yet), and if you email the company directly they may get back with their 'secret menu'

The sort used in this article is likely AliExpress or AliBaba.
Maybe I'm out of the loop but I never heard of the term energy-autark. Having looked up the definition, it means self-sufficient. Is there a reason for the use of the term autark?
Probably a German word that snuck in (the author appears to be from Germany), autark would be one of the intuitive terms in that language.
Autark might be a more common word in another language the author speaks.

It's a well defined word. Nothing wrong with using it.

The issue is that most people won't know what it means
Autark comes from ancient greek αυτάρκης (same in modern greek) which is made up from two words αυτός (he) & αρκώ (v) which means suffice, so self-sufficient.

I wasn't aware that this word existed in English but I love coming across words like these that I am not aware of, though immediately understand.