Thanks for all replies. Special thanks to Eric, ABGWD4U, and nofossil for specifically addressing my concerns.
Insulation is pretty much a non-starter for us. A large part of this building's resale value is wrapped up in the all wood interior. My exterior walls are all massive logs of varying widths with large masonry chinked seams. Their appearance within the house is really impressive. That coupled with the red cedar interior woodwork offers a really special look. Almost everyone who enters drops his/her jaw. Can't risk losing that. While I could easily add additional insulation to the attic area, payback tends to be measured in decades, same with highly energy efficient windows.
Air conditioning is of minor significance here. While everyone looks for it while looking at existing houses for purchase, it actually tends to be used sparing. We are located in a unique sliver running along Virginia's southwestern border (zone #6). We are almost 2500 feet above sea level, hence cool and non-humid summer conditions. This elevation also tends to drive winter nighttime temps down relative to what I experienced during my many years in South Jersey.
Physical condition is always a big concern once you get past a certain age. At this exact moment I am in good to excellent condition, able to do a full day's physical work. Hopefully, this will continue; however, you never know.
I, too, enjoy the challenge of unconventional ventures. My wife and I have always explored different ways of doing many things, usually to the frustration of our tightly buttoned down relatives. I must confess that that type of insanity still flows through my veins. My wife is still up for such ventures, amazing after forty years together.
Backup heating systems will be Monitor heaters, a fireplace insert (unfortunately, located at one extreme end of the house), and electric resistance in two of the bedrooms.
I really don't want to install ducts in any part of this house. There are too many associated problems. Installing an interior boiler or furnace is possible, but not practical. The house comprises two immense rooms and a very large loft upstairs. There is little closet space. Were I to go this route, I'd probably want to build an addition to the house. This is not going to happen.
Aside from the possibility of going with a wood gasifier, the only other attractive (to me) option would be the installation of a highly efficient, European style, mini-split heat pump system. Done right this would realistically cost about seven to eight thousand with most of the work being done by me. Payback on this type of system would not be quick; also, such an unconventional system might do little to increase property value. It is, however, a neat and clean solution that would provide heat and ac in one fell swoop.
The reason I am requesting info on payback and total installation cost is because heating with wood might just provide my biggest bang for buck spent. Wood can be quite cheap here. I suspect that I might be able to purchase decent hardwood for well under $100 a cord. The numerous national forests in this area can be harvested gratis under certain conditions. There is also the opportunity to purchase heavily wooded land for relatively little. Careful lumbering might actually increase land value while providing me with years' worth of fuel. K1 fuel oil now costs about $3.50 a gallon; that price will only go up over time. The differential between wood and fossil fuels is growing larger with every passing year (here I am, preaching to the choir!).
However, I am concerned that the price of a reasonable install still might require an extended payback period. My wife and I may well stay here for fifteen to twenty years. Given our ages, however, that will always be a concern. Since I suspect that the addition of a wood boiler system will not increase my property's value (indeed, it may well reduce it with many buyers), getting my money's worth out of the investment over a five or six year period is a major consideration. If I can't expect compensation on the back end (resale), then I want it on the front (through my own usage).
In reading this and that concerning this subject, I have gotten the impression that more than a few individuals have spent in excess of fifteen thousand dollars for moderate systems. Even with all that's been stated above, such a high price tag discourages one from proceeding.
Here's the URL to a nifty and adjustable comparative fuel calculator. If this has been mentioned before, please accept my apologies for the duplication.
http://www.eia.doe.gov/neic/experts/heatcalc.xls
