Comments on: Power ESP32/ESP8266 with Solar Panels (includes battery level monitoring)

By: rafa

rafa — Wed, 16 Jul 2025 22:42:08 +0000

In reply to karen zabala. cual es el caso de monitorear??

By: Sara Santos

Sara Santos — Thu, 10 Jul 2025 09:45:31 +0000

In reply to Sreekar.

Hi.
You need to disconnect the battery from the ESP32 if you want to connect it via USB to your computer.
Otherwise, it will damage your board.

Regards,
Sara

By: Sreekar

Sreekar — Wed, 09 Jul 2025 16:41:07 +0000

While using the solar panel to charge, simultaneously if i connect the esp32 with cable to upload new code or monitor the values in serial monitor, will the circuit resist it and be safe. Or will it damage my battery?.

By: Yusri

Yusri — Sun, 18 May 2025 14:23:43 +0000

I found that once battery cut off due to low voltage and then fully charged, ESP32 was not working. Why?

By: Sara Santos

Sara Santos — Wed, 12 Feb 2025 10:13:07 +0000

In reply to Lior.

Yes as long as you’re not using another power source on the USB.
regards,
Sara

By: Lior

Lior — Sun, 09 Feb 2025 12:23:07 +0000

Hi,
I read that it’s not recommended to supply voltage to the 3V pin.
I see that you provided power to this pin— is it safe?

By: zygfryd

zygfryd — Fri, 08 Nov 2024 16:02:57 +0000

In reply to Ed.schmidt.

majority are 3.3V
but, if you want 5V then I would go different way:
1- the same logic but depending on what is the device you can use:
– mosfet or
– relay
to turn them on
2- check online how to control mosfet (N-Channel) or Relay – you can use the logic from what I explained in the above post – just instead of direct power from GPIO to the device, you use the GPIO to control the mosfet or relay
3- since relay takes time (ms) you might implement some delay (i.e. 100ms) once you power it on
4- before going to sleep switch GPIO to LOW to make sure mosfet or relay are off

By: Ed.schmidt

Ed.schmidt — Tue, 05 Nov 2024 21:58:07 +0000

In reply to zygfryd. Thanks zygfryd, that will work for 3.3v devices but what about 5v devices?

By: zygfryd

zygfryd — Tue, 05 Nov 2024 18:42:27 +0000

In reply to Ed Schmidt.

why don’t you just:
1- after sleep, enable GPIO x to which you connect DHT22 (3.3V)
2- delay 10ms
3- start everything else
4- once all is done:
– disable GPIO x
– go to sleep

By: Ed Schmidt

Ed Schmidt — Tue, 05 Nov 2024 16:43:52 +0000

This is a very good article about sleep mode.
However for a temperature logger or other application you will need to switch on power to peripheral devices for them to operate. Then turn off these devices before going to sleep again.
Do you have a sketch with that type of setup?
Even a DHT22 pulls enough current (1 to 1.5ma) it will need to be turned off for battery operation.
Thanks
Ed