If the speed limit is 30, and they are driving 45, then yes they could be driving at +50% of the speed limit and be getting the mileage they are posting.

All things are relative.

 

Here's my $.02 on all this, along with some database recommendations:

• All mileage postings should be based on actual numbers, not the dashboard display. Everyone has a calculator these days; how hard is it to divide miles by gallons (or km by liters)?
• The "temperature" and "trip time" entries shold be abolished, or at least made optional. Both can be skewed by extremes. For example, if my average commute is 10 minutes but I also have a 4-hour trip on that tank, the average becomes irrelevant. Ditto for temperature (if it's 75 F on my AM commute and 95 on the PM, the average is 85, but I never actually experienced it).
• Distance & fuel entries can be made more accurate. Currently, you must round to the nearest mile and the nearest 0.1 gallon. Well, every odometer goes to 0.1 mile and the vast majority of gas pumps read to the nearest .001 gallon.
• Only the current driver should make entries. That's because different people will get different results from the exact same car based on how they drive, where they drive, etc. I recently sold my '05 HCH after averaging ~51.5 mpg. If the new owner joins GH and wants to contribute to the database, that's great, but he/she shouldn't piggyback on my results.

Just for the record, I enter miles and gallons for both our cars into Open Office spreadsheets. I compute total miles, total gallons, MPG for each tank, average MPG, and standard deviation on MPG.

 

I disagree, there has to be some way to monitor what type of weather you were driving in so you can see how it affects to mileage. I think there should be an additional pull down for rain, snow, clear, wind, etc...

Also I feel that the trip length should also be shown so that if you make a bunch of short trips, your mileage can be taken with a grain of salt since it should be lower than someone who drive the entire tank at a time. Either way, these things are only a helpful indicator, and not considered scientific absolutes. That is why they are the averages.

Quote:

Originally Posted by tanstaafl14

Distance & fuel entries can be made more accurate. Currently, you must round to the nearest mile and the nearest 0.1 gallon. Well, every odometer goes to 0.1 mile and the vast majority of gas pumps read to the nearest .001 gallon.

I agree 100%, I keep all of my receipts with the trip mileage on them, and I have to fudge the logged data by .5 miles or so so that the total miles driven does not fall behind or creep ahead.

 

I totally disagree. As a matter of fact, something should be done with respect to the temperatures and trip times. At the moment it appears they're just there "for show" and they are driving nothing.

I've been speaking to some members in this board and are all very disappointed by this hypermiling status thing here at GreenHybrid. The problem is that northern members are penalized yearly for many months in a row to such an extreme that they will never recover from a low overall average regardless of how good their summer mileage is.

The question is: "What criteria defines a hypermiler ?"

To be trully fair, the temperatures SHOULD be taken into account to at least exclude one's tanks below a certain temperature threshold. The opposite should also be true for extremely high temperatures, although the impact of lower temperatures on FE is on average far more severe than the impact caused by warmest of temps.

Since the FE loss factor is predictable and qualtifyiable why not take that into account when calculating one's hypermiling efforts? The data is there so what is trully stopping us? Oh, I see ... my apologies for suggesting it then.

So far, and going forward many of us are doubting the net worth of our contribution into this database. We cannot sort by temperature bands, nor can we see what the average FE is for any vehicle model for a range of temperatures.
With respect to those northern members who enjoy hypermiling, it looks like a no-win situation here at GH especially in the absence of a fair equalization mechanism that encourages continued contributions. Including the temperature values and having them drive additional site functionality would go a long way to make it more even handed and usefull for all.

Cheers;

MSantos

 

Definitely a spirited conversation! I also generally like the idea of moving any data from large single tanks to a historical database except for one thing. I did this very thing to keep from entering my 1st 10 tanks individually, even though I have EVERY receipt since purchase of my 2005 in Oct 2005 and used the actual gallons and miles driven. I have also wanted to see improved and expanded temparature and drive length capability, primarily because in the Dallas area in winter I may commute in to work and it be 35 degrees and when I commute home it may be 60 or 70 degrees.