1500 gal is almost 6000L.
I never cease to be amazed at how much fuel some people go through.
To put it in other terms, if you conservatively say that oil has 10.5 Kw/ L, burning 6000L yields an energy output of 63000Kw.
Have you thought about closing your doors in winter?? :0)
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How long is your winter?
I'd love to work out how much KW worth of heat you are going through a day!
I calculated oil at about 11.2 kw/L (using 145,000 BTU/gallon and 3.785L/gal)
Howdy,
I know this is a fairly old topic but it's relevant to continue it and expand a little on Oilburners excellent points above!!
The engineer in me wanted to go further!! and I'm bored today!!
From the Engineering Toolbox
https://www.engineeringtoolbox.com/energy-content-d_868.html#2 heating oil (#2 diesel) contains around 140,000 BTU per gallon.
#6 fuel oil (Bunker-C fuel oil) contains around 155,000 BTU per gallon
Waste motor oils would produce more BTU per gallon (over diesel/#2 heating oils etc) if burned efficiently because of the slightly higher carbon (soot) content but probably not more than #6 / Bunker-C oils. I think we would be lucky to get more than 145,000 btu from any automotive waste oils.
So we can probably safely assume that that waste motor oils produce should produce somewhere around 145,000 BTU/gal. (although that STILL might be a bit optimistic)
The the most efficient waste oil burning furnaces probably do not exceed 50% and even that might be a stretch. (any one here have actual data?)
Early gas furnaces (1960's -70's) were typically rated at 60% and later power vent furnaces were called 80 percenters but still vented HOT exhaust through standard "B-vent" producing exhaust temps that would burn your hand if held there.
High efficiency condensing natural gas and propane furnaces have secondary heat exchangers and exhaust blowers producing efficiencies of up to 94% and vent thru PVC plastic. You can actually hold your hand over the exhaust and it's only "luke" warm!
You cannot hold your hand over any waste oil furnace exhaust....... a HUGE percentage of the heat (read BTU's) produced are lost up the stack!
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My airplane hanger is roughly 2500 sq ft, has a 14ft ceiling and is insulated with R-21 (6" walls) and R-38 in the ceiling.
The rear door is a 12x12 insulated commercial "roll-up" and the main door is 44' wide x 14' high and 4" thick and insulated using 4" of rigid foam.
I do have some gaps on each side of the main door, about 1" on top and bottom and about 1" each side.
The only "leaks" I have are the main door which I am planning to seal up this summer.
Even so, with my 140,000 BTU/hr (rated INPUT) Lanair HL-140 (it burns about 1 gal/hr) I can bring the building to about 65F from 38F in about 2-3 hrs....but it doesn't get much higher than that.
If I'm out there for 8 hrs, I really need to run it all day. So I could essentially burn 8 gallons per day, 7 days per week if I am out there every day (which I am not)
But lets say I'm out there 5 times per week. That could be 40 gallons per week, and 160 gallons per month.
Over a typical 7month period I could burn around 1120 gallons. This is with outside temps that are never below about 10F and in most cases, not even below freezing.
Now understand, I believe I have a fair amount of heat loss through the gaps L&R, top & bottom of my main door that if plugged, would probably cut my fuel burn in half because the T-stat would shut down the furnace (that doesn't happen right now)
I also think it is probably hard to compare to an electric furnace because these furnaces are rated at BTU
INPUTElectric furnaces are rated at KW (but can easily be converted to BTU input). Just about ALL the "input" is converted to heat!! (all the air passing the electric resistance coils is heated by the hot coils................. where heat exchanger (natural gas/propane or oil) type furnaces exhaust up the stack 5-50% of the heat that goes IN!!)
Comparing an electric furnace.
A 20KW electric furnace would compare favorably to my (assumed 50% efficient) HL-140. 20kw converted to BTU is in round numbers is about 68,000 BTU (20kw = 68,242 btu)
But to get that 68242 btu from an oil furnace (at 50% efficiency) you have to burn twice that amount of oil (in BTU) or 136484 which is around 1 gallon (actually a little less if we assume 145,000 btu/gal oil )
Electric rates where I live in the PNW is about 10c per KWH (9c for the first 400kwh and 10.9c for the next 600)
Running a 20KW furnace 8 hr would essentially be 160 Kwh per day, ( using $0.10 to make it easy, $16/day or $480 per month JUST TO RUN the furnace!!)
$3360 over that same 7 month period.
Understand my wife stopped asking what time it is.............she doesn't want to know how to build a clock!!!
Somebody please check my math!!! I always make mistakes!!
Cheers,
Rick
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