Yeah I figured it on a Bu. at 56 Lb at $4/bu and divided it down to what 40lb cost would be since they did not have a Bu. tab. Then I googled the btu value of a lb. of corn at 15% moisture. I know it is not exact science but its fun to calculate it out every once in awhile to see what I am saving. I am saving some money. I dont mind tending the stove, not much else to do in the winter . And I like the fact that I buy the corn direct from the farmer right down the road . Corn only has to be trucked a few miles total from the field to my stove. That has got to cut down on some pollution I would think.Only thing wrong with that calculator is 15% RM corn is based on a bushel price not on a 40 pound bag and a bushel of corn at 15%RM is 53 pounds, not 40. I guess it you buy corn by the bag (never seen that), it would work. Myself, I don't even factor in that because I feed corn to my cattle so I just 'snitch' what I need for the stove out of the grain tank. The corn I get is pre cleaned too and at no cost to me (I actually trade for related farm operations. I plant his produce crops with one of my tractors because one of my tractors has the ultra low ground speed necessary to pull his planter with a crew of migrants setting plants, so the corn is free, sort of.
15%RM is the benchmark for storage. If you tank corn above 15%, it molds in storage and becomes unusable far as consumption for animal feed or commercial processing is concerned.
The table works, sort of and remember, I mix my corn with pellets at a 1-3 ratio to mitigate clinkers. The pellets do the same thing as oyster shell. Unlike oyster shell, pellets burn and create heat.
Field corn here is averaging around 4 bucks a bushel (53 pounds old crop) Like propane, it varies daily depending on the price set by the Chicago Board of Exchange.
I own my 500 gal propane tank and fill it once per year in late July when price is down and that carries me for the year for HW, furnace on occasion, range, clothes dryer and my gas grill is plumbed into house propane. I use about 350 gal/yr.