Allow lower output_power limit for the wifi component.

[gunplar]

Component name

WiFi

Link to component documentation on our website

https://esphome.io/components/wifi/

Describe the enhancement

For ESP devices that will be set up in extremely close proximity to wifi routers, it might be beneficial to allow very weak wifi output power, to save electricity cost, and to minimize signal interferences in small spaces.

Use cases

I have an ESP32 used to control a watering pump. It is battery powered (and solar charged), and will be mounted closed to the router. I don't need the signal to be -40dBm, but reduced power usage will definitely help prolonging the device up time.

I have applied all the wifi power saving settings I can find:

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password
  fast_connect: true
  output_power: 8.5dB
  passive_scan: true
  power_save_mode: HIGH

Anything else?

No response

[github-actions[bot]]

🏷️ I've automatically added the component: wifi label to help categorize this feature request.

[ssieb]

output_power is the only control.

[gunplar]

Is it possible to allow setting it to lower than 8.5 dBm?

[ssieb]

Looks like it could go down to 2 at for original ESP32:
https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/network/esp_wifi.html#_CPPv425esp_wifi_set_max_tx_power6int8_t
That would need a PR to change the allowed config range and verifying the range for all variants and platforms.

[gunplar]

If I can help, I have an esp32 and an esp32-c3. But I'm not familiar with esphome development.