Redshooter wrote:Propane 2.30 coal 230 ton and including the basement we are right about 4000 sq ft. And we are currently burning about 4.5 tons and 500 gallons of propane to supplement coal and heat water.
What is the BTU input rating of your propane furnace, and what is its percentage of efficiency?
If your propane furnace is one of those condensing units at 95% efficiency, then my initial guess is that it will require about 2.5 tons of coal to get rid of the remaining 500 gallons of propane that you are burning.
500 gal. x $2.30 = $1,150 for the propane
2.5 x $230 = $575 for the coal that will be needed to replace it
difference = $575 saved (or 50% for this portion of your demand)
I would also assume that the efficiency gain of the S130 over your hand fired unit would be on the order of 20%.
Putting it all together:
4.5 tons coal becomes 3.6 tons coal if the S130 is 20% more efficient then your current hand fired. [4.5 x 80% = 3.6]
3.6 tons + 2.5 tons = 6.1 tons of coal needed annually
Total new heat bill = 6.1 x $230 = $1,403
Total old heat bill = 4.5 x $230 + 500 x $2.30 = $2,185 annually
Total savings annually = $2,185 - $1,403 = $782