Saving power, IPS screen?

Hello,
After doing a bit research, I knew that Kospet Optimus 2 watch actually has IPS screen instead of OLED screen , this means that battery life can not be extended by changing white or dark color of screen saver on the watch, but battery power can be saved by setting brightness to minimum, this is not enough to save power by this, when Google Assistant Hey Google is enabled all time,