Before you can consider any sort of battery backup for your corn burner you need to determin how much electricity your unit uses. Builder's plates will tell you general numbers but if you are planning a backup system it is better to use real usage numbers.
Enter the Kill-A-Watt power meter.
The Kill-A-Watt, manufactured by P3 International, is 5" tall x 2.25' wide x 1.5" thick (not counting electrical prongs) and weighs 4.6 ounces. The bottom front portion contains an electric plug receptacle, and the bottom rear has a typical US three prong (grounded) plug. The device is intended to act as a meter, going between the item that draws power and the power source - a typical wall outlet.
To use the Kill-A-Watt, just plug it into a wall socket and then insert the plugh for the lectronic device that you wish to monitor. The Kill-A-Watt's LCD will display all meter readings: Volts, Current, Watts, Frequency, Power Factor, and VA. The unit will start to accumulate KWH and powered duration time (hour) after power is applied.
A typical corn burner (Tallcorn) reports:
I plugged my Countryside into it. It will display volts, amps, watts and watt hours.
At 123.5 volts my stove is drawing 1.30 amps with the exhaust fan and convection fan running. The fans are using 160 watts.
Add the auger and the draw is 2.07 amps-258 watts. The fans plus the stirrer draw 1.80 amps -221 watts. With the fans, stirrer and auger the draw is 2.60 amps for 320 watts.
The monitor will also give the watt hours after a period of time.
I unplugged the stove from the Kill-A-Watt this morning. For an elasped time of 38 hours the stove used 3.33 KWH. If I figure it right, that's 65 KWH per month. 2.1 per day.
My electricity bill for Oct., excluding the 1% tax, the electricity costs $.125 per KWH so $.263 per day or about $8.125 per month to run the stove.
The cost would go up slightly if the stove was burning at a higher feed rate which would have the auger motor running more.
583 KWH / 32 days=18.219 KWH per day Winter 1st step 16.438 KWH X 32 days X $.08670=$45.61 Winter 2nd step 1.781 KWH X 32 days X $.06960= 3.97 Energy cost 583 KWH X $.02080= 12.13 Basic service charge $.3492 X 32 days= 11.17 For a total of: $72.88 $72.88/583 KWH=$.125 per KWH
The Kill-A-Watt meter is available from Amazon.com by following this link: [P3 International Kill-a-Watt Electricity Usage Monitor, Ivory]
Once you figure out how much electricity your stove is using over a given time period you can then compute how much battery power and inverter size you need to run your stove for a given time period.