The MPG Illusion

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It's all crap - because the underlying premise is incorrect.

The proper way to analyse environmental impact is a 'dust to dust' consumption analysis.

If you figure out the energy and environmental (pollution) cost of manufacturing the 20 MPG replacement vehicle or even the 50 MPG econobox, you will have wasted more energy building the replacement car than you could ever save driving the replacement vehicle - not to mention, how many dollars you would have to invest in said replacement vehicle in order to save that $400 per year that the econobox 'upgrade' would generate.

So the correct answer from an environmental perspective is neither - keep the vehicle you now own and drive less or at least take it easier on the gas pedal.

If you MUST buy a new vehicle, the best upgrade is to replace the pickup with the 50 MPG econobox. Why? Because for every mile you travel you will consume less fuel than you would driving any of the other three vehicles. It isn;t about how few gallons of fuel you consume per distance travelled relative to the vehicle you are driving NOW, but rather the overall fuel consumption for driving the distance, period. So no matter how you figure it, you are better to be using 2 gallons of gas to travel 100 miles than using 4, 5 or 10.

Yes, you will SAVE 5 gallons per 100 miles if you move from a 10 MPG unit to a 20 MPG unit - but if all you are doing is moving people down roads, then the 50 MPG unit is the right one.

Perhaps more to the point, if you buy the 50 MPG econobox you'll save even more, because you won't want to drive the uncomfortable, cramped econobox as many miles as you would your 25 MPG sedan.

 
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The entire rest of the world measures fuel usage for their cars as consumption. So does the aircraft industry and the marine industry. Consumption is fuel per distance, or fuel per time. Liters per hundred kilometers, or gallons per hour.

Americans measure fuel usage for their cars as efficiency, distance per fuel. The ONLY reason to do so is that a bigger number is better, so that's gotta be the right way, right?

Better consumption is a lower number. Lower can't really be better, can it? No way!

He of the wheelie avatar above is correct in stating that if you want to save gas, dump the SUV and get an econobox, don't just get a more efficient SUV. What the Duke boys are saying, college-educated wonders that they are, is that the MPG improvement does not follow a linear scale in actual fuel usage improvement. What sounds like a huge leap, say 41 mpg to 51 mpg, is no better in actual gas savings than improving from 14 to 15 mpg. Each saves a hair under half a gallon per hundred miles.

Apparently the American public is not good enough with numbers to see this, and we require the advice of post-graduate academic dudes.

Lastly, if you're gonna dump the SUV for an efficient little coupe, don't spend too much money doing it. 30,000 bucks buys an awful lot of gas, even at over $4 a gallon. It might take longer than the life of the efficient car to save enough gas to justify the change. Something else we're apparently not good enough to figure out without academic assistance.

 
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I learned a long time ago: If it involves math, the masses are screwed.

 
I dumped my 16 mpg truck for a 45 mpg FJR.

At least that's one reason I used to convince my wife!!!

 
I dumped my 16 mpg truck for a 45 mpg FJR.At least that's one reason I used to convince my wife!!!
My wife saw the $200 receipt, and asked how much change I got...when I said that didn't fill the tank, she asked how much these bikes I've been whining about for years cost, and what kind of mileage they get:) 14mg->45mpg...almost what the Duke guys pointed out :)

Mike

(The commute vehicle the fjr has idled is a diesel F350 long-bed crew cab dually.)

 
Tires are the big ongoing cost for bikes. If you spend $300 every 6K miles for tires and installation that's 5 cents a mile. If you go 45 miles on $4 of gas that's almost 9 cents a mile.

Tires for a typical car cost less than 1 cent a mile.

 
Tires are the big ongoing cost for bikes. If you spend $300 every 6K miles for tires and installation that's 5 cents a mile. If you go 45 miles on $4 of gas that's almost 9 cents a mile.
Tires for a typical car cost less than 1 cent a mile.

GOOD Point...and when you factor in comfort, safety and abilty to work while I commute the 11 miles to work...I save little to nothing!!!! I'll keep the 17mpg truck.....

 
GOOD Point...and when you factor in comfort, safety and abilty to work while I commute the 11 miles to work...I save little to nothing!!!! I'll keep the 17mpg truck.....

Soooo you're one of these cell phone using road hazards we're all complaining about? Or do you hold meeting on the way to work?

 
I managed to increase the efficiancy of my 21 mpg, 200$ a month in fuel to drive Toyota FJ Cruiser. I bought an FJR, now the Toyota only cost me about $50.00 a month to drive. So I guest its getting 84mpg now! :dribble:

 
I just bought a new car. To help with my analysis, I threw together a quick spreadsheet that does what these guys talked about...and I'm just a college dropout!!!!

Column A = Current Gas Price

Column B = # of miles per month

Column C = Average MPG

Column D = Gas Cost per x # of miles (Column B/Column C) * Column A

I did iterations of Column A at $4, $4.50, and $5.00 to see what the future outlook was.

After all this logical thinking, I threw it all out the window, along with some of my monthly discretionary $, when I replaced my relatively decent mileage TL with a thirsty MDX. Guess I am a dummy afterall.

 
Soooo you're one of these cell phone using road hazards we're all complaining about? Or do you hold meeting on the way to work?

I am hands free......and I do seriously look out for bikes but other than that GUILTY has charged.

 
I go through this exercise every year when we think about replacing Excursion.

i.e. gets 11mpg and is paid for vs... Something compatible for comfort, safety, size for hauling people kids, and all there **** and able to tow what ever it is I need to tow.

The cost of that replacement vehicle $25-$45k) vs. the 15-18mpg I *might* get never computes.

On the flip side my son had been driving our old Econoline van (which is somewhat an oxymoron), which ran a nice 15MPG. It too is paid for. But when we had the opportunity to provide him with a clean and sporty Ford Escort ZX2 that got 30mpg, we jumped. Of course we only paid $1500 for that. At the rate he's putting on miles it will be paid for in 3-5 months or 10k miles. All things considered that made sense.

We can't replace our Excursion, for what we use it for, with an econo-box, that's simply not an option.

 
Economically,

What are the typical increased medical costs due to increased trauma due to being in a smaller mass econobox while being head-on'd by larger mass vehicle (say Excursion perhaps). I would say the mileage savings wouldn't balance out then.

 
I somewhat match the example used.

I have a large truck for scuba gear and she has a SUV(older durango, before they got as big as they are now). I can't go from the truck to small car. However, I might be able to go to a larger SUV or smaller truck. She also might be able to go to a smaller car.

 
like most around here i have a small truck and and my bike as a second mode of transportation. Most short and in town trips i use my 04 Dak, out of town i use the bike. i find that my truck and FJR can make the same amount of distance from one tank.

07 FJR fill up around 22.00 @ 4.44 per gal

04 4.7 Dakota around the 60.00+ zone @ 4.44 per gal

as a side note: my monthly gas bill has not dropped, as i ride more often then i drove (my 04 dak has only 30K miles on it)

 
OK, I'm a tree-hugger and not a very good one at that, but gee whiz fellas, maybe it shouldn't only be about whether or not it saves me some money to go to a highly fuel efficient vehicle. Continuing to drive a gas guzzling, polluting monster because it saves a few bucks compared to the "econobox" is a losing strategy. Think about the mess we are in because of dependence on foreign oil, polluted cities, ever hear of global warming? There are OTHER costs besides just what you lay out for the vehicle that might be more important in the long term. End of sermon.

 
I go through this exercise every year when we think about replacing Excursion.
i.e. gets 11mpg and is paid for vs... Something compatible for comfort, safety, size for hauling people kids, and all there **** and able to tow what ever it is I need to tow.

The cost of that replacement vehicle $25-$45k) vs. the 15-18mpg I *might* get never computes.

On the flip side my son had been driving our old Econoline van (which is somewhat an oxymoron), which ran a nice 15MPG. It too is paid for. But when we had the opportunity to provide him with a clean and sporty Ford Escort ZX2 that got 30mpg, we jumped. Of course we only paid $1500 for that. At the rate he's putting on miles it will be paid for in 3-5 months or 10k miles. All things considered that made sense.

We can't replace our Excursion, for what we use it for, with an econo-box, that's simply not an option.
Here's another way to look at things:

The GREET Theory

The eye opener based on 160,000 mile vehicle life span:

* Hummer H2: 13,913 gallons ($44,800 at today's prices!), 1579.13 mmBTU* Toyota Prius: 2,883 gallons, 327.207 mmBTU

* Toyota Highlander: 6,400, 726.4 mmBTU

* Toyota Highlander Hybrid: 5,424, 615.593 mmBTU
Note that those are July 2007 gas prices. Figuring today's $4.50/gal fill-up, that H2 number turns out to be $62,600.00! :eek:mg:

Considering I traditionally accumulate between 30,000 and 40,000 miles on my vehicles, at an average of 35 MPG, over the 160,000 miles quoted above for each of my 3 vehicles and based on today's gas prices... $61,715.00 or $20,570/vehicle. That's $4,571/year/vehicle life vs. $13,714 for the H2.

Yikes.

 
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