The only two skills that consume corpses by default are Corpse Explosion and Raise Skeleton. I just tested this quickly and yes, Raise Skeleton does give me the expected small jump in essence.

I thought that both raising a skeleton and using corpse explosion consumed a corpse. I know for sure that corpse explosion generates essence for me. And I’m 90% sure that raise skeleton does as well.

However, corpse tendrils does not consume a corpse.