Energy allows you to use items that require energy, like guns and jetpacks. Energy slowy depletes when using items that require energy. If you start running out, it will slowly regenerate, but if you keep trying to shoot with no energy left, this will cause a "life support brownout" and do temporary damage to your health.
Batteries can be used to give you more energy, so you are able to shoot for a longer period of time.
Generators can be used to help regenerate your energy more quickly, so that you can fire more rapidly without depleting your energy.
Firing weapons to deplete your energy sometimes causes your energy level to increase - as of the latest update, however, the amount of the increase has been reduced.
There are three energy attributes:
-Max Energy: The maximum amount of energy you can have. Increased by batteries.
-Regeneration: The speed at which your energy regenerates. Increased by generators.
-Energy: Increases both Max Energy and Regeneration. This is a player stat that can be increased by depleting your energy.