To keep it simple we are in the process of buying a house that we know is going to need new systems. 5400 sqft Triple brick, but badly insulated. Forced air and water from Propane at $1,000 a month. No Natural Gas available. Plentiful wood available locally at less that $100 a cord. Free if you clear it yourself - pine beetle. Our plan: Definite Insulate, refurbish windows (Historic Building) Wind power tied to grid. All the usual options to minimise electricity consumption PV not currently cost effective, wait for the next generation. Solar Hot Water is cost effective, probably tubes as we will be high (9,500ft) and it can get very cold. So we are thinking of: Stainless Steel Wood Gassificaton Boiler, c 250,000btu, in a new building which would be big enough for all our systems and be insulated to the hilt. Large water tank to provide storage fed by Boiler and Solar. Water to be used for radiant heating and domestic hot water, initially it would be linked into to the forced air system as it will be a year or so before we can fit radiant baseboards. I have not seen a good US supplier, this is what I had in mind: http://www.discreteheat.co.uk/ So does the above make sense? We need a back up source, so I was thinking of keeping the Propane, would a separate Boiler be best, a few I have found allow dual fuels but then you may be limiting your choice. I was thinking with a big enough water tank, if you kept it fired up then you would be good for a weekend away, longer than that and you have the Propane making sure things do not freeze. There is also a wood stove in the main room, but I doubt if it is very efficient and certainly not placed to heat the whole house.