Frank might be onto something with the corn burner. Truthfully, I think Gern has a good firewood source. Buys some, cuts some. Last we spoke this was the case. Myself? I am fortunate to have all the equipment a guy would need to easily handle massive quantities of wood. I am closing in on 40. Been heating exclusively with firewood the last 7-8yrs. Maybe a little longer. My parents are supplied by me as well. They might use a cord or two a year maximum. They have a wood burner and it is more supplemental now as compared to nearly an exclusive heat source when I was a kid. If an indoor unit is out of the question, there goes the ideas of an insert, corn burner, buck stove. . .
If outdoor unit is what you want, do some serious math. Add up your heat bills. Figure your cost of the unit to include underground pipe, fittings, chain saws needed, trailer, splitter, etc. Say your expenses are $8000 and heating bills are $2000/yr. Four year return on your investment. That doesn't include your time and gas to get firewood. That is free. At 25-35yrs old, $2000/yr in savings really helps justify the expense. I am not sure I will want to be doing the firewood thing when I am 60-70-80yrs old. Hope I am able to, but not sure i will want to. At 45-50yrs old I will start losing my helpers as they graduate. lol