Ask me at the end of the heating season, when I find out exactly how many tons of pellets I need to replace the 600 gallons of oil that I've historically burned.
If you go by a pure btu to btu comparison, which is what it seems that most people are doing, that should be 4.5 tons. But after 2 months of burning, I can tell you, its not going to be anywhere near that many pellets. Much closer to 3 tons. These pellets are MAGIC, I tell ya
Seriously, the "magic" is that my fha system wastes a lot of heat into the basement. WAY more than I realized. While burning pellets, in a stove, in my living space, I'm not wasting any heat into the basement. I'd probably realize the same effect if I moved my furnace up to the first floor; I'd burn less than 600 gallons...but it would be loud and ugly.
Most of the fuel comparison calculators out there only account for the heating appliance's burner efficiency. They don't factor in the delivery loss...(of which, there is none, with a stove.). I did see one calculator that factored in the loss, but I can't remember where it was. Anyway, it had a field for "burner efficiency", but then also had fields to fill in for the delivery (water or air), and then sub-descriptions beyond that. For "FHA", the choices were for how much insulation was on the ducts. ("no insulation", then a couple of choices for a couple of types of insulation). I don't know how to grade what I see in my house; there is a main "bus" type duct that runs the length of the basement, which is wrapped with some type of insulation...attached to it, are the round ducts that lead to the room registers...what I see on these ducts is no insulation; but I seem to remember, when they were building the house, that the pipe sections inside the walls were wrapped with something. no way to check that, now. anyway...
If you choose "no insulation" on the ducts, the efficiency drops to 50%. With better insulation, the rate goes up...so my "real" efficiency, based on BTU's of heat actually delivered to the living space, is somewhere between 50 and 80%, and thats on the day that I get my burner tuned up, so that its actually getting 80%.
Factor THAT into your calculations, and $300 pellets still aren't a bad deal, even with today's low oil prices. Not a huge "boon", but way better than what the straight btu calc shows. and way, WAY better than simply moving the decimal point over.
The problem with this is, my house isn't like your house. My stove isn't like your stove, and my pipes aren't like your pipes. Well...maybe they are. The point is, its not an easy comparison, and its not accurate for anyone to make absolute statments like "x pellets = y oil". There are just too many variables to consider.
