I will say the DE has a LOT to do with battery life. KDE and Gnome are pretty heavy, Xfce is pretty lite, and LxQt is even lighter.
Of course all the other stuff make a difference too (24 browser tabs, 4 VMs, 3 podman containers, a Postgresql DB, a web server, it can add up in a hurry. But Then I hardly ever run in battery mode.
Of course all the other stuff make a difference too (24 browser tabs, 4 VMs, 3 podman containers, a Postgresql DB, a web server, it can add up in a hurry. But Then I hardly ever run in battery mode.

