28.

Nikolai Kardashev has categorized civilizations based upon the amount of energy that a civilization can expend (measured in total watts) over its lifetime, each type increasing its usage of power by ten orders of magnitude above its prior stage of development. A Type I civilization can access the energetic potential of an entire planetal system, expending 10¹⁶ watts in the course of development; a Type II civilization can access the energetic potential of an entire sidereal system, expending 10²⁶ watts in the course of development; and a Type III civilization can access the energetic potential of an entire galactic system, expending 10³⁶ watts in the course of development.⁴¹ A Type IV civilization (not identified by Kardashev but theorized by others) might conceivably access the energetic potential of an entire cosmos, achieving an almost divine power over the physics of reality itself.