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Power

Conversions

Energy density

Derived Units

A kilowatt-hour is ↑6.5 energy: ↑3 (kilo) + ↑0 (watt) + ↑3.5 (hour).

A food calorie (kcal) is ↑3.6 energy: ↑3 (k) x ↑0.6 (cal).

1 “toe” (ton of oil equivalent = 10 gigacalories) is ↑10.6 energy. So an “Mtoe” (million tons of oil equivalent) is ↑16.6 energy.

Example: Human power consumption

Energy statistics are given in a variety of units, like MToe/year and TWh/year. MToe/year is ↑16.6 (as above)

The world produces ↑20.5 energy per year. Factoring out the year (↑7.5) gives ↑13 power.

So humans need 1000x more power to become a Kardashian Type I civilization.

Example: Calories in, Calories out

Human energy needs are about 2000 kcal per day: ↑3.3 (“2000”) ↑3.6 (“kcal”) ↑-5 (“per day”) = ↑2 power

And, in fact, human power output is ↑1.5 power at rest, ↑2 power with exertion, ↑3 power at peak.

Example: Kardashev Civilizations

The sun radiates ↑27 power, and the earth receives ↑17 power from that.

Kardashev Type I/II/III civilizations are ↑17/↑27/↑37 plus or minus ↑2.