Fuel cost analysis

I'm thinking of buying a new vehicle one of these days/months/years, and was wondering how the cost breakdown really works on fuel economy. Note that this spreadsheet just attempts to estimate fuel costs.

I generated a spreadsheet and was a bit surprised at the results.

Some scenarios:


15,000 miles per year, gas averages $3/gallon, 50% city driving, 50% highway driving

The hybrids are definitely more economical to operate, but surprisingly don't offer too many advantages over their conventional siblings. With gas at ~$3 per gallon, buying one becomes a chancy proposition on payoff.

25% city, 75% highway
75% city, 25% highway

Ah, but gas prices have stablized at $3 per gallon now ... what if they jump to $5/gallon? There seem to be any number of geopolitical events that could cause this...


15,000 miles per year, gas averages $5/gallon, 50% city driving, 50% highway driving

The hybrid premium still looks a bit dicey, but if you're hedging your bets it may be the way to go.

25% city, 75% highway
75% city, 25% highway

But the snowball keeps rolling...


15,000 miles per year, gas averages $7/gallon, 50% city driving, 50% highway driving

I'm not sure I'd want to be driving the Hummers or anything below 25 MPG city at this point.

25% city, 75% highway
75% city, 25% highway



A note about my data ... I know that EPA mileage estimates are rather unrealistic so I was able to find some more "real-world" numbers for some of the hybrids as indicated in my spreadsheet. All other numbers are EPA values, which are typically off by as much as +20%.

Thanks Idle...I've always wondered what the mileage numbers would look like when calculated the way you've done here. As I suspected, the hybrids do rule the fuel economy roost, as far as total cost of fuel goes.

I would add that hybrids have additional air pollution and noise advantages over conventional vehicles, as well as impressive cruising ranges. In the abscence of a reasonable EV alternative...

Not to nit-pick but......

If you compare EPA numbers to "realistic numbers it invalidates the spreadsheet since you are looking for relative costs. If they are all inflated it is closer to accurate (for this purpose).

Second, you are looking at the "hybrid premium" without taking into account the residual selling price of the car. If the purchse price is $3000 more but the resale is also $3000 more then there is no premium. Another way to look at the "premium" is to look at all the other cars you might also buy. I was looking at a $45,000 Jaguar when I bought my $23,000 Prius. That's a $22,000 savings. The same works if you are looking at any $30,000 sedan.

Third, the highway/freeway ratios are difficult to quantify for most people. Most people around here either commute, so the ratio is 95% highway, 5% city or they work/shop locally, so its' 95% city and 5% highway.

Last, your spread sheet shows a lot of cars that are not in the same class. The Insight will not fill the same role as a Camry, and a Camry will not fill the role of the Escalade. You could compare full sized diesels with 2 seat coupes, but it's kind of meaningless. Well, except for the appreciation of the fact that my Prius saves me $3,500 a year in gas over the Silverado. at $7.00 a gallon.

I would recommend hybrids anyway (if they are practical for you) since they are more efficient and (generally) better for the environment. They are also fun to drive, with a power curve that is not matched by any other kind of car.

If your sole desire is to save money, you can't beat buying the cheapest, lowest power car you can find and driving it to death. Well, you will do better if you find a fuel efficient car that does not depreciate much and sell it before it needs repairs. But that's off topic.


Daniel (hmmmmm Guess I was nit-picky )

I ackowledge that this exercise has flaws. I don't have time to make it perfect. I would discourage anyone from using this spreadsheet as the sole method for determining which car to buy next. It only attempts to analyse annual fuel costs without considering what you'll be using the vehicle for (I'm sure that the Silverado hybrid would be a much better jobsite vehicle with its integrated ~2kW generator than the Prius). I tried to stick to vehicles that I've seen used as family / commuter cars and avoided pure commercial vehicles. I also tried to include as many hybrids as I could find information on since those are the new big thing from Detroit and Tokyo. Diesels are obviously missing. I drive my vehicles into the ground, so resale value is of no interest to me.

The odd mix of vehicles is about one third cars I was somewhat interested in buying, one third average family cars, and one third extreme examples. I'm missing obviously minivans, full-size sedans, and some other categories I can't be bothered to remember.

Heck, my driving is probably closer to 80-90% highway but I also idle the vehicle every now and then for somewhat long periods of time... so 25/75 seemed like a good split in addition to 50/50.

I used actual test for the hybrids deliberately to drag their numbers down a bit so that folks would see that they still have real fuel savings verses (inflated) EPA ratings for regular vehicles. I'm not knocking hybrids by doing this; just holding them to a higher standard where they still exceed.

It's not so easy to find "real world" numbers on regular cars because people aren't so interested in them. Feel free to hunt down better data. I provided the source file. I can provide an Open Office .SXC file if you'd like.

It's not disputed that owning a heap requiring regular maintenance is the cheapest car to own; although it's apt to be a tad unreliable. Assuming it's not a guzzler and gas doesn't spike yet again.

:mecry: :mecry: :mecry: 7$ /gallon is science-fiction for you?
I just calculate our prices in $ and gallons, it's 6,7 $/gallon !
Thank god, that the average european car is more economical and my second hobby behind flashlights is mountain-biking:laughing:

Your comparison of cost per mile is lacking.

To get true 'operating' cost per mile you need to average in typical maintiance costs... and with hybrids that it a big unknown. Parts? Labor? Typical issues? Battery replacement? Etc.

Datasaurusrex said:

Your comparison of cost per mile is lacking.

To get true 'operating' cost per mile you need to average in typical maintiance costs... and with hybrids that it a big unknown. Parts? Labor? Typical issues? Battery replacement? Etc.

Click to expand...

AHEM. Let's try again here.

idleprocess said:

I ackowledge that this exercise has flaws. I don't have time to make it perfect. I would discourage anyone from using this spreadsheet as the sole method for determining which car to buy next. It only attempts to analyse annual fuel costs without considering what you'll be using the vehicle for...

Click to expand...

Note the emphasis.

We're estimating fuel costs only, not cost of ownership, operational costs, or total effect it will have on your own share of per-capita GDP.

idleprocess said:

AHEM. Let's try again here.



Note the emphasis.

We're estimating fuel costs only, not cost of ownership, operational costs, or total effect it will have on your own share of per-capita GDP.

Click to expand...

Just comparing fuel savings, on a cost per mile basis, is mental masturbation, no 'real world' use.

Those hybrids will have costs that end up offsetting any fuel savings.

They use fairly exotic parts, and will be 'dealer' only servicable for some time to come.

The problem is the numbers are not all inflated consistently. For example Consumer Reports found that hybrids produce on average, 19MPG less than their estimated EPA city mileage numbers--by far the worst discrepancy they have ever found in all their years of testing.

Now 19MPG less than those numbers is still excellent mileage, but no better than some regular cars without the price premium. And many of the tested cars could actually beat their EPA highway ratings, because the EPA highway cycle varies from 60MPH down to 30MPH.

I'd suggest using Consumer Reports' numbers instead, because they are observed numbers using a random sample.

Idleprocess,

Thanks for doing the charts. They are very informative regarding fuel costs. Ignore the nitpickers :nana: and others that talk about EPA estimates, true costs of maintenance, resale, blah, blah, blah. This is a chart about FUEL COSTS, and although they may not be perfect, they are helpful. Thank you! :goodjob:

Another issue with "real world" mileage, especially on Hybrids is they may very well be inflated. People spend the extra $2k-$5k on a Hybrid because they have justified the cost with all the benefits. This makes them have a vested interest in high MPG so not to make themselves feel foolish. I suspect most of the people reporting their "real world" hybrid MPG do so when it makes them look smart. When they get MPG that's less than what they expect they stay quiet or write it off to an anomaly. When they get an exceedingly good result they post it. To help achieve the good result they probably drive more conservatively than the average driver so it sort of skews the "real world" for the average / not concerned driver. I compare it to gamblers. When they win they talk and talk about it. When they lose it generally stays pretty quiet.

I have done quiet a bit of non-hybrid "real world" informal testing over the last 5 years on many, many types of vehicles. What I have discovered is City MPG is nearly always lower than what the EPA says and highway MPG is nearly always higher. My most often tested vehicle, I probably tested 30 of them, is a 2005 new body style Malibu. I consistently get 21-23 city and 34-37 highway. Most others I test get the same type results. 2-4 lower in the city and 2-4 higher on the highway. I'm at sea level but have tested up to about 800' MSL. I have no idea if the Hybrids will perform differently but look forward to some non-owner testing.

idleprocess said:

It's not so easy to find "real world" numbers on regular cars because people aren't so interested in them.

Click to expand...

In 2008 the EPA numbers should be much more realistic. While still not perfect, they should be a lot closer to actual numbers than the silly test they do now. For example in the new test many hybrids will show a lot lower EPA number than they do now, which is in line with actual real world numbers many people have noticed...

If you haven't lookied into the EPA tests they do now is a complete joke!

For example the hiway test are done in lab with a warmed up engine (no cold starts) and assume an average 48mph (with no more than 60mph) and only very gradual speed changes! In other words, nothing like the way people drive...

Donovan said:

If you haven't lookied into the EPA tests they do now is a complete joke!

For example the hiway test are done in lab with a warmed up engine (no cold starts) and assume an average 48mph (with no more than 60mph) and only very gradual speed changes! In other words, nothing like the way people drive...

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That's interesting and makes my real world test seem odd. For fun I have done a whole bunch of speed test in the 05 Malibu with the cruise control set at 45-50 MPH. I get 42-48 MPG which is significantly more than the 32 MPG highway from the EPA. I have repeated the test several times in several different cars. Admittedly there is no accel or decel which would bring the MPG down quickly.

DieselDave said:

That's interesting and makes my real world test seem odd. For fun I have done a whole bunch of speed test in the 05 Malibu with the cruise control set at 45-50 MPH. I get 42-48 MPG which is significantly more than the 32 MPG highway from the EPA. I have repeated the test several times in several different cars. Admittedly there is no accel or decel which would bring the MPG down quickly.

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That is a sweet spot for a lot of cars. If I pick the sweet spot (46 MPH IIRC) in my Prius, I can get MPG numbers in the 60s, but that assumes that I don't waste energy by starting, stopping or changing speed. I don't see a lot of spots where I can drive non-stop at that speed.

The EPA test includes speed changes, but not the actual aerodynamics.

Daniel

Real world? Here you go.

Bought an '06 Prius on 2 Jan 06 for my wife's use. She makes, in her job, lot's of short in-town trips with a few city freeway miles. She's a very aggressive driver. Over 7,000 miles on the car now. Her mpg is 41 to 43. Last months 800 mile highway trip with me driving (more aggressively than usual due time factors) was 51mpg. Driving style makes a big difference - when I drive it in town over a period of several days, my mpg generally exceeds 45mpg. (BTW this is all done with the a/c cranked way down!). These mpg numbers are real - I fill the tank and do the math.

Because of the $3,150 tax credit, the excellent warranty, the tech and safety stuff, fuel economy, anticipated residual value and the environmental issues this was a no-brainer. Nothing else came close.

Since the head tech at the Toyota dealership is a good and trusted friend and fishin' buddy, I learned that the repair and battery replacement concerns are non-isssues. His experience is that the Prius rarely needs repairs. His dealership has never replaced a battery pack. He regularly services several of the cars with over 200,000 miles which are still functioning very efficiently on their original batteries. The "$6,000 battery replacement" is a 'net legend.

And, unusually, not a moment of buyer's remorse.

Thanks BIGIRON...I, for one, am glad to hear the opinions of those who have been lucky enough to buy a hybrid. I suspected the web-myths and fears regarding servicing and dependability would be proven false.


BTW, the EPA fuel tests max out at 60 mph!!!

Hell, you'll get a ticket for going too slow on the highways of California if you try to cruise along at 60...what a joke.

I also wonder how accurate the EPA system is when it comes to vehicles that use regenerative braking...with a difference of 19 mpg between the manufacturer's stated figures and their results, I'd suspect the EPA's testing is flawed.

I really look at the EPA figures as comparatives only, just as I do the stuff at Consumer Reports, Car and Driver and Sister Juanitas Crystal Ball Emporium.

If EPA says Dodge p/up is 14/18 and Ford p/u is 15/19, I'll assume the Ford MIGHT get a little better mpg.

I've never expected EPA results to predict real world mileage and have certainly never experienced them to be correct (with one exception -- my MBZ turbo-diesel gets exactly the EPA numbers in nomal driving).

BIGIRON,
Wow, the tax credit is up to $3,150, that should help bring mass production faster and offset the extra up front cost which makes them even more attractive. Real world for you is a bit less than what's often reported by other owners and less than the real world #'s shown in the spreadsheets by about 20% in the city which makes sence with running the AC and more normal type driving. Few people putt along anymore.

Are the batteries in the Prius Lith-ion?

Datasaurusrex said:

Just comparing . . . is mental masturbation, no 'real world' use.

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Thats 99.46% of what most of us do here.

Idle - I know you are just comparing fuel costs, so plz forgive cause I'm going to run astray here. But I'm betting that when one looks at the big picture, it ends up being overall least spendy to buy and drive a low mileage, reliable '99 Camry or whatever vs. any new hybrid thats going to depreciate away 60% of its value in the first 48 months.

Lots of things to consider here, but thats what makes it fun.

cheers