What features are slowed down when using the energy saver mode for the battery in the mac?
when i set my macbook to energy saving mode, i would like to know what impact it has on performance
Low Power Mode?
About Power Modes on your Mac - Apple Support
Change Energy settings on a Mac desktop computer - Apple Support
"Reduce energy usage for computers that are always on (such as those used as servers) and fan noise for environments and tasks that require minimal noise."
Apple doesn't get any more specific than that.