Compact 1x1 loader requiring electricity to run. There are options to enable or modify capabilities like stacking, disable power consumption, or recipe cost.
I suppose this is just a me issue but i cannot stand the way the loaders use power. I would prefer they just have a high power draw instead of the "spiky" nature they have. I just turn the power requirement off but that just feels cheap acceptable i guess but cheap none the less.
Power is consumed while it is active just like all the other entities in the game. Inserters "spike" when they swing, labs when sciencing, assemblers when assembling, loaders when transferring items.