Somewhat related thought: World power consumption is around 20 TW (of which around 3 TW electricity), that's very roughly 2 kW per person (obviously not equall

Somewhat related thought: World power consumption is around 20 TW (of which around 3 TW electricity), that's very roughly 2 kW per person (obviously not equally distributed). A human consumes around 8600 kJ of energy in their food per day, or roughly 100 W (search for "basal metabolic rate"). Most of that is needed just to keep the body running, but around a quarter or so can be converted to physical work: an average human can perform some 75 W of physical work over an 8h shift (75 W for 1/3 the time, so 25 W on average). That means that everyone has (on average) around 80 "people" worth of energy working for them (2000 W of energy consumption per person / 25 W of average usable energy output per person).