This is a super quick toggle to change into a personal energy-saving mode on a Lenovo T490 (Ubuntu 19.04)

charge_threshold.sh

#!/usr/bin/bash

while true; do
        read -p "Toggle charge threshold? [y|n|q]" yn
        case $yn in
                [Yy]* ) sudo tlp setcharge 75 80; echo "tlp setcharge 75 80"; exit;;
                [Nn]* ) sudo tlp setcharge 70 95; echo "tlp set charge 70 95"; exit;;
                [Qq]* ) exit;;
                * ) echo "Please answer with [y|n] for toggles or press [q] for quit."
        esac
done

power_saver.sh

#!/usr/bin/bash
while true; do
        read -p "Toggle powersaver? [y|n|q]" yn
        case $yn in
                [Yy]* ) xset dpms 60; sudo cpupower frequency-set -u 1.2GHz; sudo prime-select intel; echo "CPU power 1.2GHz, dpms 60, prime-select intel"; exit;;
                [Nn]* ) xset dpms 0; sudo cpupower frequency-set -u 4.8GHz; sudo prime-select on-demand; echo "CPU power 4.8GHz, dpms 0, prime-select on-demand"; exit;;
                [Qq]* ) exit;;
                * ) echo "Please answer with [y|n] for toggles or press [q] for quit."
        esac
done