Determining Farm Power Loads Page

When sizing the generator you want to first select the season with the greatest demand for electricity in your operation. For example, if you use electricity for grain drying, the fall season is likely the time with greatest demand. Increase the required capacity of your generator by at least 10 % if you want to use your generator for long periods of time (not just during power failures.) Finally, increase the required size of your generator to allow for future anticipated electrical loads.

Generators need to be sized correctly to prevent overloading. Overloading a generator can cause poor power quality, and may damage the generator and electrical appliances in your barn and out-buildings. In order to determine the generator's size, make a list of what will be operating, and add the wattage of all the equipment. Be particularly cautious when calculating and connecting motor loads as starting wattage can be considerably higher than operating wattage. Refer to motor nameplates when making these calculations. Otherwise, horsepower (about 850 Watts per HP) can be used to determine the generator size. Motors require three to five times more current for starting than for continuous running.

Farm	Running Wattage Requirement	Starting Wattage Requirement

Electric Fence, 25 miles	250	250
Feed Conveyor	800 ? 5,000	2,700 ? 18,000
Feed Grinding	1,000 ? 7,000	4,000 ? 25,000
Feed Mixing	800 - 2000	2,400 ? 7,000
Grain Cleaner	650	1650
Grain Elevator	1000	2400
Kango Hammer	900	1200
Milk cooler (bulk)	1,500 ? 12,000	7,500 ? 60,000
Milking Machine	500- 5,000	2,000 ? 17,000
Milking Machine, 2hp	1,800	5,800
Mixer 3 ? cu ft.	2,800	7,700
Portable Conveyer	1000	2400
Silo Unloader	2,000 ? 7,500	7,000 ? 26,000
Space Heater	1,000 ? 5,000	1,000 - 5,000
Stock tank De-icer	1000	1000
Ventilation Fans	300 ? 1,000	1,000 ? 3,500
Water heater	4,500	4,500
Water Pump	500 ? 2,500	2,000 ? 10,000

Farm Loads - Sizing Your Generator:

Farm