Ares as a project has a goal of accuracy at any cost, so tends to need a lot more resources than most other emulators. Before the tragic loss of Near, they wrote an absolutely exceptional article about the development of bsnes/higan and how much power it required for cycle-accuracy of SNES hardware, and it’s way more than you would think is feasibly necessary given that emulators like ZSNES (or Gens, as was my Sega emulator of choice at the time) ran under a crappy Celeron in the 90s.
I will say your CPU will likely throttle back well before it’ll shut down due to overheating. It might affect emulation performance some, but your PC shouldn’t shut down or anything.