MPG Efficiency Score

I have been thinking about this for a while. How can we compare various trips with an MPG Efficiency Score? Bear with me here!

I wanted to compare the variables of a trip and combine them into one score. The variables I came up with is miles, MPG (real) and Avg MPH. I needed a way to weight each one of these variables so that when they are all combined a single score is tallied for comparison to other trips.

Miles should directly affect the score, but if the other variables are the same, and you go twice as many miles, should your score double? I don't think so, but the farther you go at a given MPG and Avg MPH should increase the score.

Obviously, MPG should be the highest weighted variable since this is what we are trying to increase. But, if you go 2 miles at Avg MPH of 20 mph and get 70 MPGs, how would that compare to a trip of 30 miles averaging 40 mph and getting 55 MPGs?

The last variable of MPH needs to be fairly heavily weighted so as not to overly reward a high score for going too slow. When people post their trip info, very few put in the Avg MPH.

So, I came up with what I thought would be the perfect hybrid vehicle stats and this would be a score of 100. Everyone would love to see 1,000 miles out of a tankful of gas. If a rough tank size was 10 gallons, of usable fuel range, then you would have to get 100 MPGs to achieve the 1,000 miles per tank. Also, most people would love to go 75 MPH and achieve the last two variables.

I'm sure this would be up for debate, but humor me here! So now the key is to come up with a weighting factor for each variable to achieve a perfect score of 100.

Here is what I came up with:

Var. Factor Score
Miles x .06 1,000 x .06 = 60
MPG x .25 100 x .25 = 25
MPH x .20 75 x .20 = 15
-----
100

I have attached a spreadsheet file in which you can plug in various trips and compare them to one another. You can compare tankfuls or shorter individual trips to each other.

As an example here are some results:

Miles MPG Avg MPH Score
34.7 62.7 41 26.0
35.0 63.3 38 25.5

608 53.8 39 57.7
521 56.9 30 51.5

With the spreadsheet it's easy to see how each variable affects the overall score.

I know this was a long post and I hope everyone understands my concept. Please feel free to comment and suggest changes!

 

I have re-posted this in the Prius Fuel Economy Forum:

http://priuschat.com/forums/gen-iii.../108878-mpg-efficiency-score.html#post1551750

 

From Wikipedia:

[ame=http://en.wikipedia.org/wiki/Efficiency]Efficiency - Wikipedia, the free encyclopedia[/ame]

Efficiency in general describes the extent to which time or effort is well used for the intended task or purpose. It is often used with the specific purpose of relaying the capability of a specific application of effort to produce a specific outcome effectively with a minimum amount or quantity of waste, expense, or unnecessary effort. "Efficiency" has widely varying meanings in different disciplines.

The term "efficient" is very much confused and misused with the term "effective". In general, efficiency is a measurable concept, quantitatively determined by the ratio of output to input. "Effectiveness", is a relatively vague, non-quantitative concept, mainly concerned with achieving objectives. In several of these cases, efficiency can be expressed as a result as percentage of what ideally could be expected, hence with 100% as ideal case. This does not always apply, not even in all cases where efficiency can be assigned a numerical value, e.g. not for specific impulse.

Maybe it should be called MPG Effectiveness Score?

Since a ideal score of 100 is comprised of:

1,000 Miles (Tankful)
100 MPG
75 Avg MPH

Everything is measured against that with the variables having different weightings. That's why I didn't give a lot of weight to Miles. If you double your Miles should your score double? Whereas if you double your MPGs or MPHs, your score won't double, but it will make a significant difference.

 

I understand what you are saying, but I tried to come up with a quick comparison method.

Throw some of your stats in and see what scores you come up with.

My best short trip score of 34.8 miles was 26

My best tankful score of 608 miles was 57.7

 

I'm not saying to do one or the other and I understand real world scenarios. I am just providing a mechanism to compare various trips to one another.

When some of the people on this site write how they got 70 MPG and averaged 27 MPH for 10 Miles, I just wanted a way to compare it to my daily commute of 35 Miles at 63 MPG and averaging 38 MPH.

BTW - 38 MPH may sound slow, but on a 35 mile commute during rush hour with some bumper to bumper and local traffic, it's actually not that bad.

 

I admit there are flaws in the equation. It is probably best used for similar type trips (miles) for comparison. The maximum should probably be a tank of gas, since the ideal was based on getting a 1,000 mile tank.

How would you weight the MPGs vs the Avg MPH? Is it better to get 50 MPGs at 40 MPH or 40 MPGs at 50 MPH? Or, do you consider them equal?

I'm just throwing out a mechanism for comparison. Also, when people report their MPG results, they should also report Avg MPH as something to evaluate.