A 400 gallon propane tank holds 320 gallons of propane when full ( 80% )
1 gallon propane yields roughly 95,000 btu's.
320 gallons x 95,000 btu's = 30,400,000 btu's
A 500 gallon propane tank holds 400 gallons of propane when full ( 80% )
1 gallon propane yields roughly 95,000 btu's.
400 gallons x 95,000 btu's = 38,000,000 btu's
1 full cord of firewood = 4' high x 4' wide x 8' long or 128 cubic feet.
1 full cord of Osage Orange produces roughly 32,900,000 btu's per cord.
Based on Hedgerow's stack of Osage Orange:
58" high / 18" / 16' long wide ( x2 )
4.833 x 1.5 x 16 = 116 cubic feet x 2 = 232 cubic feet. ( 1.8125 full cords )
( 256 cubic feet = 2 full cords )
232 cubic feet of Osage Orange = 7,632,800,000 btu's.
What does this all mean?
You will need to fill a 400 gallon propane tank 251 times to = the same btu's as Hedgerow's stack of Osage Orange!
80,320 gallons of propane = 7,630,400,000 btu's
232 cubic feet of Osage Orange = 7,632,800,000 btu's.