I wonder what my 1HP single speed pump was pulling, you think it was just 1000 watts ? It seemed to cost a lot to run
The problem with the rated hp of a pump is that it doesn't mean much unless you know the service factor.
A 1 hp pump with a S.F of 1.25 will use about 1,250 watts. A 1 hp pump with a S.F of 1.65 will use about 1,650 watts.
The motor label will specify the voltage(s) and the amperage(s) of the motor.
For example, the motor might say 115/230 volts and 10/5 amps.
At 115 volts, the maximum amperage should not exceed 10 amps, which is 1,150 watts.
At 230 volts, the amperage should not exceed 5 amps, which is also 1,150 watts (volt-amps).
Typically the actual amperage will be less than the full rated amps.
A 230 volt motor rated at 5 amps will use about 4.5 to 5 amps, which means that the power will be about 1,035 to 1,150 watts or volt-amps.
To calculate the cost, you have to multiply the kilowatt hours by the cost per kilowatt-hour, which can vary by time of use.
For example, a 1,000 watt pump will use 1 kilowatt-hour per hour.
If the cost per kilowatt hour is 10 cents, then the pump costs 10 cents per hour to run.
If the cost per kilowatt hour is 25 cents, then the pump would cost $0.25 x 24 x 30 = $180 per month to run continuously 24/7.