the system input power (in watts) for a lamp-ballast combination.

Active power is the real power (kW) supplied by the generator set to the electrical load. Active power creates a load on the generator set's engine and is limited by the horsepower of the engine. Active power does the work of heating, turning motor shafts, etc.

The power (in Watts) used by a device to produce useful work. Also called input power.

Also known as â€˜Real Powerâ€(tm) or simply â€˜Powerâ€(tm). Active power is the rate of producing, transfer or using electrical energy. Measured in watts and often-expressed in kW or MW.

Active power, measured in watts (W), is the product of the voltage and the component of current power in phase with the voltage.

Product of voltage and the in-phase component of altering current measured in units of watts and standard multiples thereof, that is:
1000 Watts = 1kW
1000 kW = 1 MW
www.edwt.org/glossary/a