How are you powering your ESP32 devices?

ESPHome
1

Most of what I currently have are dev boards (Adafruit, M5Stack, Espressif, etc) just plugged into a USB wall charger temporarily, but as I am trialing more sensors in a wider number of areas it’s becoming more obvious that I am going to need other power options as well.

Battery
From what I understand most ESP32 boards are not particularly suited to battery power from an efficiency standpoint (or at least older models weren’t) and I have also noticed very few dev boards come with LiPo charging circuits. Can battery power be done feasibly?

Hardwired?
Certain locations like an unconditioned attic seem like they would be better suited to some form of hardwired low-voltage power source more along the lines of how a doorbell is powered as opposed to a long USB cable.

POE seems like an option but almost unnecessarily complex unless you are also wanted to hardwire the data connection as well.

As much as anything I am kind of curious about how most people power their stuff.

2

Low power battery powered projects for sure benefit from careful ESP32 selection.

Typically you’re relying on low deep sleep idle currents.

The video linked here is a good starting point.

3

I also only have development boards and pretty much exclusively use USB, regardless of whether its just got a single sensor soldered directly to it or it’s attached to a PCB I made up. The only exceptions are if I need more power (i.e. boards used to control strip LEDs) or I need 12V: in both of those cases I just use a barrel jack and an AC adapter.

The big reason I go this route is that I have so many random USB cables and plugs I’ve accumulated, so it’s typically free and also easy.

4

Same here; just using up the collection of old USB cables and plugs I have lying around. And they’re cheap enough to buy at any department store if you run out.

I did try a battery powered device once, but it killed the battery (a bank of 4 AA’s) so fast that I abandoned that idea. The things I’ve needed so far don’t really lend themselves to a deep sleep. I think if I needed battery powered devices, I’d use an off-the-shelf Zigbee door, temperature and/or humidity sensor. That should cover just about all my needs.

5

I use 18650 battery shields with 3,3v and 5v output they come with a usb connection for charging (TP401 or so?)

the only thing i need to sort is a easy way to read the voltage via an ADC pin so
and some method it can allert me when the USB wallwart isn’t supplying any power

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