Computing Motor Operation Costs

In trying to shave farm energy costs, it's good to know what your electric motor costs are relative to the total utility bill.

Table 1 below shows the energy costs associated with operating single-phase motors. To calculate electricity consumed, multiply the running kilowatts by your cost per kilowatt-hour for the horsepower motor you have. For example, a 2 HP motor running 3 hours per day on $.07 per kilowatt-hour electricity would cost 42 cents per day (2 KW x 3 hr x $.07/KW-hr = $.42).

As a quick guide to make calculations simple, allot 1 kilowatt per horsepower of motor capacity. The starting kilowatts is important to know when figuring loads to be started by standby generators.

Webpage maintained by: Bob Schultheis Natural Resource Engineering Specialist Email comments to: schultheisr@missouri.edu Last revised: 11/21/2007

University of Missouri Extension does not discriminate on the basis of race, color, national origin, sex,
sexual orientation, religion, age, disability or status as a Vietnam-era veteran in employment or programs.