I have come up with various schemes for heating our home efficiently, cheaply and safely. In the past they have all revolved around a hydronic system since we already have baseboard heat. However, we lose our service contract for our oil furnace if we tie in to the system with a solid fuel boiler. Plus hydronic systems need to stay above freezing at all times and since there is no chimney space for another appliance in the house, we would need it in an add-on or in an out building.
Here come’s the magic: wood burning forced hot air furnace. It gives you redundancy (run out of oil, still have wood heat/have a leak in the baseboard, still have forced hot air), it would allow the burning appliance to be in an unheated, unplumbed (ie-cheaper to build and easier to insure and get permits for) add-on to the house and it wouldn’t matter if you went on vacation for a week (the oil would keep the house warm like it does now, and the add-on and furnace would get cold but it wouldn’t matter).
So here is the plan:
- Home heat: Wood forced hot air/oil boiler with baseboard heat
- Hot water: Solar hot water/oil boiler (with indirect tank setup)
- Run the oil boiler with a outside temperature reset
Right now we are heating entirely on oil and burn 650 gallons/year for our 1,250 square ft home. With this new setup I would expect to burn less than 50 gallons/year. This would save us $1,500 per year. Even accounting for gas and wear and tear on the truck getting wood as well as chainsaw fuel and maintenance etc that would mean we’d still save a minimum of $1,000 per year and a maximum of $1,300 per year.
Let’s do some math:
Furnace – $3,100
- $1,100 – US Stove hot air furnace model 1357M
- $1,500 -add-on to house
- $500 – chimney and other hookups
40 gallon Tank water heat zone for oil – $1,500
Solar hot water system – $3,000
Total cost: $7,600
In 6-8 years time we would be saving money.
Immediately we would be saving the environment.
Over the lifespan of the systems (25 years or so) we would save between $17,000 – $25,000.
I would estimate that 80% of the savings here is through the wood furnace alone. That said, you could pay less than half of the initial burden and get most of the gains of this system.
