Hi Michael,
yes, I take issue with that particular chart as well. The overall approach is fine but they do not indicate how they arrive at their "multiplier" and I suspect it is skewed to better illustrate their point of view. To be fair, there is a great deal of grey in matters relating to efficiencies of appliances and BTU content in certain types of fuels. There are no black and white, definitive, answers to how efficient a pellet stove really is or how many BTU's are in a cord of wood. For that matter, the price of a cord is hard to pin down since many local sources obscure the price by supplying less than a cord or wood by the "truckload".
I have done some spreadsheet calculations of my own and I have used some conservative efficiencies and thermal properties of fuels to come up with the following multipliers:
Code:
Fuel Cost Multiplier $/MM Btu
Electricity 0.15 x302.1 = $45.31
Propane (LP) 2.25 x14.0 = $31.46
Natural Gas 1.76 x12.8 = $22.56
Wood Pellets 200.00 x0.081 = $16.16
No. 2 Fuel Oil 2.72 x8.93 = $24.29
Cord Wood 150.00 x0.067 = $10.00
The method used for these multipliers is as follows. Not everyone agree with these efficiency or BTU numbers.
Code:
Fuel Cost Unit BTU Input Net Effiency BTU output units/MM BTU
Electricity $0.15 kWh 3413 97.0% 3310.61 302.059
Propane (LP) $2.25 gallon 91690 78.0% 71518.2 13.982
Natural Gas $1.76 therm 100000 78.0% 78000 12.821
Wood Pellets $200.00 ton 16500000 75.0% 12375000 0.081
No. 2 Fuel Oil $2.72 gallon 140000 80.0% 112000 8.929
Cord Wood $150.00 cord 20000000 75.0% 15000000 0.067
You can take all these calculations with grain of salt. Adjust for your area and use common sense numbers to make reasonable comparisons.
Sean
I'm sorry for the poor formatting. I can't figure out how to manipulate the HTML to put everything in the proper columns. Is there a way to post in plain text? I'll try to attach the spreadsheet file.
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Michael said:
Found this on Travis Industries site
http://66.14.95.152/CostOfHeating_WkSht.asp?P=2
Try punching in some numbers. It’s just not realistic.
I came up with $20 to heat my home with electricity per month. HA! That’s a good one! It’s off by about $300-400. If it only cost $20 a month to heat with electricity, I would’ve been hard pressed talking wifey into a new wood burner.
Wood was a slightly different story. I put in $150 a cord (going rate around here) and came up with $10 a month. Who can honestly heat their home on $10 a month???