Posting a vehicle’s fuel efficiency in “gallons per mile” rather than “miles per gallon” would help consumers make better decisions about car purchases and environmental impact, researchers report.
Inspired by debates they had while carpooling in a hybrid car, management professors Richard Larrick and Jack Soll ran a series of experiments showing that the current standard, miles per gallon or mpg, leads consumers to believe that fuel consumption is reduced at an even rate as efficiency improves. People presented with a series of car choices in which fuel efficiency was defined in miles per gallon were not able to easily identify the choice that would result in the greatest gains in fuel efficiency.
For example, most people ranked an improvement from 34 to 50 mpg as saving more gas over 10,000 miles than an improvement from 18 to 28 mpg, even though the latter saves twice as much gas. (Going from 34 to 50 mpg saves 94 gallons; but from 18 to 28 mpg saves 198 gallons).
These mistaken impressions were corrected, however, when participants were presented with fuel efficiency expressed in gallons used per 100 miles rather than mpg. Viewed this way, 18 mpg becomes 5.5 gallons per 100 miles, and 28 mpg is 3.6 gallons per 100 miles — an $8 difference today.
“The reality that few people appreciate is that improving fuel efficiency from 10 to 20 mpg is actually a more significant savings than improving from 25 to 50 mpg for the same distance of driving,” Larrick said. (See table above)
John was chuckling over this headline in his Tech5 podcast the other day. I decided to Post the article to lead folks to the details.
Essentially, Americans suck at arithmetic. This system is supposed to be easier for the math-challenged to understand. Even if you get the car builders and retailers to adopt the new system, I think the average American ain’t going to have a better understanding of comparative fuel consumption.
the metric system makes so much sense…
ok well come to think about it.. since i own the thread… simple math says whatever is easiest to convert to dollars per mile is best for consumers, maybe
I guess seat miles per gallon makes no sense either. Or gallons per hour. Maybe pilots can figure out that 19 gallons per hour / 6 chairs * 195 kts GS isn’t that bad considering that they don’t wait to board or wait in traffic (when traveling between outlying airports).
And those outlying airports just happen to be much closer to the ultimate destination as well.
Can you fly from DFW to Atlanta cheaper than you can drive (fuel only, based on occupancy)? Absolutely. And no TSA, either.
You don’t want to own a plane, you just want a friend that owns a plane. 🙂
I have to agree that if a person is too “math illiterate” to understand that getting MORE miles per gallon is good, then how are they going to understand that LESS gas is good?
Usually, the math illiterate equates more with better, not less!
This is similar to the european standard of liters per 100 kilometers. I guess whatever you get used to ends up making sense, all you need is some means of comparison.
#5 Hardly a European standard, I never heard or seen it used. The standard seems to be km/L, which makes perfect sense.
The only reason mpg doesn’t make sense is beacause neither miles nor gallons make all that much sense.
Usually you have some idea of where you’re going and how fare it is, then is’t pretty simple to figure out how much pertrol you’ll need and what it cost. The other way arround would make it more complicated to figure out for most people.
Nows the time to go metric. Do you think Americans would be happier if they only had to pay $1 a liter for gas?
Huh! I had presumed that the 10K miles thing was based on some mix of city/highway which would make it more easily interpreted into cost than the typical 18/25 city/hwy ratings.
Hey! Let’s create a new standard based on actual test. 5 days of commuting and errands around town followed by a weekend trip to the seashore 300 miles away by interstate. Total gallons consumed.
Surely “miles per dollar” would be the simplest indication?
I like how GM has been advertising their SUV’s they compare mileage now to other SUV’s. I really think advertising should include actual mileage figures. In fact you go to web sites like GM and Ford and you really have to dig around to find the MPG figures. Of course they openly advertise the good ones.
So lemme see… I’m much better off getting 20 mpg than 50 mpg if my previous Mastodon got 10 mpg? Of course, why couldn’t I see that before?
#6 – Simon – Hardly a European standard, I never heard or seen it used. The standard seems to be km/L, which makes perfect sense.
From directive 1999/94/EC:
Miguel (#5) wrote I guess whatever you get used to ends up making sense, all you need is some means of comparison. So true. But the metric system is more logical, but tell that to someone who grew up with imperial units. 😉
#11
Exactly! It seems these people don’t want to MAXIMIZE fuel economy. They are playing a percentage game that does nothing to help our current situation.
Example: If i have a truck getting 1 mpg and buy a truck that gets 2 mpg, then I’ve doubled my fuel economy. So what! You still drive a gas pig that does little to reduce fuel prices and dependency on fossil fuel!
It’ll definitely make converting to and from L/100km easier. Downright painful now.
Logical huh?
Seems to me if “cost” is the most import issue then whatever formula you use should express “the cost” of the item involved as in Dollar per (some unit).
So “logically” what is the second most important factor? Distance? Capital Recovery? Carbon Footprint? Mean Time Between Failure? Next Overhaul? etc.
The US Tax code allows deductions based on cents per mile. Many businesses allow expense reimbursement on cents per mile.
I love talking to Mercedez Owners who brag about their cars being cheaper to drive because they are so reliable. Fact is, the cost of their Warranty Preserving First Tune Up is more than the cost of my current car.
Logic has nothing to do with anything except logic. What are your values?
In Canada our official fuel economy measurement is the standard L/100km. It’a a nice system because if I am going on a trip of 650km I know I can take my fuel rating, multiply by 6.5 to figure out how many liters I’ll need. Multiple that by the current cost of fuel and I know a rough idea of what the trip will cost.
That’s simpler than dividing the MPG into the total miles and then multiplying by the price of gas. I think comparing the amount of fuel burned over a certain distance makes more sense than figuring out distance per a certain amount of fuel.
Naturally, having grown up with MPG it takes awhile to get used to it. Even know when I see a rating in L/100km I need to convert it into MPG to get a number that tells me if that mileage is “good” or not.
In Canada our official fuel economy measurement is the standard L/100km. It’a a nice system because if I am going on a trip of 650km I know I can take my fuel rating, multiply by 6.5 to figure out how many liters I’ll need. Multiple that by the current cost of fuel and I know a rough idea of what the trip will cost.
That’s simpler than dividing the MPG into the total miles and then multiplying by the price of gas. I think comparing the amount of fuel burned over a certain distance makes more sense than figuring out distance per a certain amount of fuel.
Naturally, having grown up with MPG it takes awhile to get used to it. Even now when I see a rating in L/100km I need to convert it into MPG to get a number that tells me if that mileage is “good” or not.
#15 Bobbo – “I love talking to Mercedez Owners who brag about their cars being cheaper to drive because they are so reliable. Fact is, the cost of their Warranty Preserving First Tune Up is more than the cost of my current car.”
I never have owned a Mercedes but would venture to guess that a new Mercedes wouldn’t need a “First Tune Up” until 100,000 miles. Many owners would trade in there vehicle prior to accumulating that many miles.
This simple fact is why they should drop the CAFE limits, instead of raising the fuel mileage requirements. Doing this would make many SUVs disappear, as people would go towards large cars which disappeared after the CAFE rules were passed. So instead of 15mpg SUVs, you have 24 mpg cars.
Pardone! Me thinks the point of cost has been lost in the point of math dumbs expressed as comparative efficiencies. Two dumbs don’t make a better sum. Or a false dichotomy (or did someone just get a lobotomy?).
Yes, the jump from 18 to 28 mpg saves more gas than does the jump from 34 to 50 mpg. But the base issue for saving fuel is efficiency at any particular mpg rather than this “word problem.”
As stated it misleads (news reporters, particular, who always seem hard-studies challenged). The news lead from the idiots on radio “news” the other day led one to think that this study was saying that 28 mpg used less gas than 50 mpg.
There was also a report earlier in which some researchers (?) (math teachers?) were saying that the tradition of word problems really lost the math in a distraction and contributed little or nothing to good math thinking. Competing-expert stories.
With the goal of reducing fuel usage (forget specified-range comparisons) the higher mpg always means less fuel used for the same distance traveled. That is really the only useful calculation (word problem) for 99.97% of car consumers.
#15 – bobbo
Not sure what your point is. Are you arguing that the imperial system is better or at par with the metric system?
I use mortgages/year.
#17–Radom Chevy Insulter==well, it has been a few years since I talked to a Mercedez Owner. Back when I drove a jagolet. (Jaguar car with a chevy engine). At that time the cost of the engine change was paid for in two tune up and you got a car that didn’t leak oil and actually started.
So the Mercedez vs Chevy==which is cheaper per mile to drive verses cheaper to own over a given time span? Seems instead of a Mercedez, I could buy a chevy and just drive it until it fell apart and then get another chevy and be way ahead of the game? My uncle used to do that with Cadillacs, but he turned it in every 2 years.
Issues are all the same though—logic having little to do with values, whether they be saving the earth, or being ostentatious.
#20–Jag==you are most usually humorous by association. Don’t you have a picture of a commanding Imperial Gallon vs a Napoleonic Liter?
Actually, #13, if you RTFA you might have noticed the guys who did the math got the idea whilst commuting in a Hybrid Camry.
# 7 – ArianeB
I know for sure Canadians would be happier if they only had to pay $1 a liter for gas! 🙂
#19, Mike,
Good point. This argument is total bullshit, trying to compare apples and oranges.
***
I am in the market for a light duty pickup The actual final choice will be a combination of factors.
Is it compatible with the rest of my fleet?
What are the net capacity limits? (bed size and weight)
What is the towing limit? (do I need or want to tow trailers)
How many passengers can it carry? (put the family in for a trip)
What is the reliability history of the make / model?
How easy is it to maintain? (can I do it or must a mechanic)
What are the insurance costs? (they do differ between makes for similar vehicles)
What color / options does my wife want?
Can my wife drive it (she won’t drive a standard shift)
All of the answers here will be as important as the economy. For example, the cost of replacing something could be a simple do it yourself or a $2,000 shop job. How much more efficient would another model need to be to offset that repair?
Fuel efficiency is a great concept BUT it is not the major factor in vehicle ownership. First is purchase price, plus loan interest. Second is the insurance. Down the list is fuel.
I would be so happy to pay 1$ per litre…
Price here is 1.5 Euro per litre, which means 2.25$ /litre. And 67% of it goes straight into the treasury’s pockets…
I’ve been calculating my costs as cents per mile. Mostly to see if the bus is economic for me. My Diesel Jetta is currently $0.105US per mile. For my commute, the bus would be more expensive because of all the transfers and add an hour each way.
#23 – bobbo
?
#29–Jag==you often post humorous and/or informative weblinks. Your post at #21 is a complete misread of what I posted, having nothing to do with Imperial vs Metric Measurements, so I thought you were making a joke that I didn’t get.
So, I’ll give you one back re #21——“?”
Easy to misscommunicate on the interwebitudes.