Using Ohm's Law, 1500 watts of energy uses 12.5 amps. Ohm's Law defines the relationship between amps, watts and resistance. In the United States, electricity has a resistance of 120 volts.
The relationship defined by Ohm's Law is:
I = V / R
I is the current in amps, V is voltage in watts and R is resistance in volts.
An amp measures the amount of electrical charge that passes through a point in a circuit. A volt represents the potential for energy movement, similar to water pressure in a pipe. A watt is a unit of power, measuring work done when 1 amp flows through 1 volt of electrical potential difference.
In other countries that utilize voltage of 220 watts, 1500 watts would use 6.81 amps.