Community Forums

GaryKD · 11-21-2007, 01:25 PM

Fuel Efficiency Calculation

None of the following will change the $s flowing out of your pocket. I present this only as an additional way to look at the same situation. I've been trying to figure a way to give the coach credit for towing a vehicle and the total weight being moved down the road. The usual MPG calculation does not seem fair. In addition, I have not found an accurate way to compare towing and not towing fuel consumption. Here is my idea.

For years railroads have used a calculation to show fuel efficiency. It shows how many miles a gallon of fuel can move 1 ton of weight. After completing our fall trip, I thought this would be a good time to make the calculation and maybe start thinking about fuel usage a bit differently, in the future, than we have in the past.

Trip highlights are:
Total Miles = 3688
Total Fuel Used = 491.4 gallons
Total Coach & Toad Street Weight = 34147 lbs

Past thinking says the coach got 7.5 miles per gallon. (This is a .2 MPG increase over previous trips, it was cold and no dash A/C was used).

Now for the new miles per ton calculation:
1. Find the total ton miles by dividing the lbs weight by 2000 to get the weight expressed in tons. 34147/2000=17.0735 tons. Then take the total miles and multiply by the weight in tons. 3688X17.0735=62825.08 is the total ton miles.

2. Next take the total ton miles/fuel consumed=miles per gallon of fuel. This is 62825.08/491.4=127.84916 miles per gallon of fuel for each ton of weight.

I think this is a good way to express fuel consumption of an RV.

An example of my toad, on this trip is:
Total miles = 1306
Total Fuel Used = 89.2
Toad Street Weight = 5174 lbs.
Past thinking says the toad got 14.6 miles per gallon.

1. Completing the same #1 calculation is 5174/2000=2.587 tons. 1306x2.587=3378.622 ton miles.

2. Completing the same calculation for #2 above is 3378.622/89.2=37.876928 miles per gallon of fuel for each ton of weight.

The coach at 127.8 miles per ton and the toad at 37.9 makes the coach 3.4 times more fuel efficient than the toad!

I like it!

GaryKD · 11-21-2007, 01:25 PM

Fuel Efficiency Calculation

None of the following will change the $s flowing out of your pocket. I present this only as an additional way to look at the same situation. I've been trying to figure a way to give the coach credit for towing a vehicle and the total weight being moved down the road. The usual MPG calculation does not seem fair. In addition, I have not found an accurate way to compare towing and not towing fuel consumption. Here is my idea.

For years railroads have used a calculation to show fuel efficiency. It shows how many miles a gallon of fuel can move 1 ton of weight. After completing our fall trip, I thought this would be a good time to make the calculation and maybe start thinking about fuel usage a bit differently, in the future, than we have in the past.

Trip highlights are:
Total Miles = 3688
Total Fuel Used = 491.4 gallons
Total Coach & Toad Street Weight = 34147 lbs

Past thinking says the coach got 7.5 miles per gallon. (This is a .2 MPG increase over previous trips, it was cold and no dash A/C was used).

Now for the new miles per ton calculation:
1. Find the total ton miles by dividing the lbs weight by 2000 to get the weight expressed in tons. 34147/2000=17.0735 tons. Then take the total miles and multiply by the weight in tons. 3688X17.0735=62825.08 is the total ton miles.

2. Next take the total ton miles/fuel consumed=miles per gallon of fuel. This is 62825.08/491.4=127.84916 miles per gallon of fuel for each ton of weight.

I think this is a good way to express fuel consumption of an RV.

An example of my toad, on this trip is:
Total miles = 1306
Total Fuel Used = 89.2
Toad Street Weight = 5174 lbs.
Past thinking says the toad got 14.6 miles per gallon.

1. Completing the same #1 calculation is 5174/2000=2.587 tons. 1306x2.587=3378.622 ton miles.

2. Completing the same calculation for #2 above is 3378.622/89.2=37.876928 miles per gallon of fuel for each ton of weight.

The coach at 127.8 miles per ton and the toad at 37.9 makes the coach 3.4 times more fuel efficient than the toad!

I like it!

Route 66 · 11-21-2007, 02:28 PM

Excellent!

UPS 34 · 11-24-2007, 04:08 AM

I think that is a good way to look at it. I look at driving a Motor Home VS A 5th Wheel. I get to where I go and drive a Honda. My Sister drives a 5th wheel and gets to where we are going and then still only gets 8 MPG. Im starting to justify the extra cost of the MH

Jestme13 · 11-26-2007, 10:49 AM

Hmmmmmmmm

David K · 11-27-2007, 01:12 PM

I like it !!!!!!!!!!!

Sure does make it sound a lot better.

Izzyblueye · 11-27-2007, 03:58 PM

Looks good. But if "wishes were horses, beggars might ride".

Ray,IN · 11-27-2007, 06:58 PM

Wonder what your calculations do to the QE2? She gets 6 inches per gallon of #6 oil.
Your suggestion is an enlightened way to view traveling.

read & learn · 11-28-2007, 05:19 AM

Gary
My one question is,where do you take speed into your calculations--55mph--60mph or faster will this change the miles per ton

GaryKD · 11-28-2007, 07:18 AM

Hi read & learn,
Speed is taken into consideration because of the amount of fuel used. I travel between 60-62 on the Interstates and the speed limit on secondary roads. If I travel faster or slower, the fuel consumption would be different. The result of the step #2 calculation would be different if the fuel used was more or less than in my example.