From where does electrical power derive? Explain it.

(N/A) Electrical power is the rate at which electrical energy is transferred or converted into other forms of energy (such as heat,light,or mechanical work) by an electric circuit.
It is derived from the work done by the electric field on the charge carriers (electrons) as they move through a potential difference $V$.
When a charge $dq$ moves through a potential difference $V$,the work done is $dW = V dq$.
Since current $I = dq/dt$,the rate of doing work (power) is $P = dW/dt = V(dq/dt) = VI$.
Using Ohm's law $(V = IR)$,the power can also be expressed as $P = I^2R$ or $P = V^2/R$.