Wattage is volts times amps

that 80% rule is for continuous draw... the breaker trips at the %100 value

Go back to school please

DC wattage is voltage times amps.

AC wattage is voltage times amps times the

power factor.

The 80% thing is a design rule that an electrician has to follow if he wants the wiring to pass inspection.

The 80% rule has nothing to do with electricians or passing inspection

that is the design of a circuit breaker

electricians have rules as to wire size ... number of fixtures/outlets ... size of breakers

they must follow

yes ac wattage includes PF .. do you have any clue what power factor is