The latest statistics from the Energy Information Administration show that diesel is actually .03 cents per gallon cheaper than gasoline on a national average. Whereas gas prices have risen considerably since their December low, the drop in diesel prices was slower, making the bounceback less extreme. According to CNN, the price parity can be traced to inventory levels. Gasoline inventory has been dropping bringing prices up more sharply. Meanwhile, diesel-making distillate supplies are increasing. Longer term, the Department of Energy expects diesel and gasoline prices to rise but not by as much as had been previously anticipated.
According to estimates published in Transport Topics, diesel is expected to average $2.26/gal this year and $2.48 in 2010. According to the same estimates, gasoline will average $2.12 this year and $2.30 next year. After a year of crazy ($3.26 average in ’08) gas prices, this recovery is sure to create headaches for product planners. Not only are hybrids no longer the “it” technology, but diesel could maybe, just possibly, become a viable option once again. Who’d have thunk it?
Just how the hell is anybody supposed to run a business when a crucial commodity price swings wildly all over the place?
Few car companies will make the investment in compliance with balkanized diesel emission regs if the price of the damn fuel goes from double the price of gas to less than gas in 9 months, and will probably go back again in another few months.
I love diesels, but if I were running a car company I’d stay far away from the screwed-up US with them, for sure. VW seems to sell a few, BMW has sold almost none, and I don’t know about MBenz. Everyone complains about the American consumer perception of diesels, but I don’t think the historical issues are the problem anymore. The problem is a screwed-up message: they are legal in some states (hopefully all new models are 50-state, but who knows when regs will change again), they are around for a few years then disappear (VW Taureg diesel, Jetta’s 2 yr haitus), some need urea refills, some don’t, the fuel is crazy expensive..no…wait..now it’s cheap…no…sorry…it’s expensive again.
One more reason to have an elastic gas tax. Not only it’ll make fuel dearer and will help factor in the externalities it generates in air and noise pollution from car travel, but it will smooth out prices at the pump, making planning easier for everyone from carmakers to vacationers to trucking companies.
As much as (an albeit small) percentage of Americans love diesels, the very fact that it is such a small percentage virtualy guarantees that even with price parity, diesels won’t ever be considered as a viable option for large-scale volume sales. During my previous travels to Germany, I always rented diesels…love them! But here in the good ol’ US of A, they are still viewed in terms of being slow, loud and a tad odiferous!
Public perceptions aren’t the problem. Purchase price is the problem. Diesels cost more to make, and your typical American is focused on the up-front cost.
As for fuel price swings–no one can say with much certaintly where prices will be in six months. The key way manufacturers can “plan” for this is to have a broad product portfolio and truly flexible manufacturing.
The only reason Diesel is EVER more expensive than gasoline is due to taxation. Before Diesel was taxed at such a steep rate it was always cheaper than gasoline, by an average of 50%. In the 1980s, when I started driving a Diesel car I paid about 65¢ a gallon for Diesel #2, when unleaded gasoline was $1.20 a gallon.
While today’s ULSD is a tad more complex than the Diesel of yore, it is still a vary basic distillate of crude oil compared to gasoline.
As for cars, I’ll never buy a new gasoline-powered car again in my lifetime if I can avoid it. I happily get 50 MPG in a 5-passenger sedan on home-made fuel. You can’t do that with gasoline.
–chuck
the downside is much higher maintenance costs IN GENERAL
anything to do with the fueling system in diesels is often multiples of gasoline… eg. thousand dollar fuel pumps etc.
I have 2 diesel tractors and a diesel combine on my farm. Love them but for one thing: Don’t try to start them in cold weather.
Western Europe doesn’t have the very cold temperatures that we do in the Northern States and Canada. I don’t try to start the tractors until about 32 degrees F., and that’s after having them plugged in for about an hour and using starting fluid.
Unless you have a way to keep a diesel warm at 10-20 below, better not buy one if you need a ride in very cold weather.
I wish Chrysler had done better in sales with their diesel Liberty and Grand Cherokee. If I could have afforded a new one I would have bought it but I wasn’t in the market. Sadly GM killed most peoples perceptions of diesels in the early 80s. Although I know with proper maintenance a few guys have gone hundreds of thousands of miles in their old diesel Oldsmobiles.
My other vehicle is a scooter and I wish it was technically feasible to build a diesel scooter. CVTs try to keep an engine in the meet of it’s torque curve.
I think the drop in diesel is due to a decline in diesel consumption based on the decline in truck mileage. Once the economy picks back up [don’t hold your breath] diesel will most likely go higher than gas. And the diesel engine is more expensive at purchase too. I read that diesels are losing favor in europe in favor of the new more fuel efficient gas models. Just my .02 worth. I like my prius very well and prefer it over any comparably priced diesel cars.
chuckgoolsbee: The only reason Diesel is EVER more expensive than gasoline is due to taxation.
Chuck, how come you won’t let go of this incorrect generalization? It’s not anywhere near true at all.
Diesel and gasoline are global commodities, and traded that way, based on supply and demand. All you have to do is look up the current commodity price for unleaded and heating oil #2 (essentially the same as diesel). Last October, in the thread that is linked in this post, I responded to your identical comment with the then current prices: (untaxed): unleaded gasoline – $1.48; heating oil (essentially diesel)-$1.97.
The reason diesel ran higher the past few years is because the economic boom in developing countries caused a disproportionate increase in demand for diesel, because it’s used heavily in industrial applications: trucks, ships, etc. Refineries CANNOT just shift output from gas to diesel. It’s much more complicated than that. With the global slowdown, diesel demand has fallen faster than gas demand, for the inverse reason given above: industrial uses have dropped more than automotive uses.
I appreciate your strong feelings about diesel (and Tercel tailgates, and use of showers by Eugenians), but that doesn’t make them correct.
Because most diesel is consumed for large-scale business use, I suspect that gasoline prices are more elastic than diesel prices. Many people can cut down on the use of their gasoline powered car when prices are high. Ironically, those people might cut down on their own personal gasoline use by taking public buses or trains, thereby increasing diesel consumption.
Why does the price of diesel seem to hit parity with gasoline every few days? Seriously.
Even on the same website, I’ll often see two stories several days apart, each saying that, for the first time in a long time, the price of diesel equals the price of gasoline.
Like, no way!
Michael Karesh:
“Diesels cost more to make, and your typical American is focused on the up-front cost.”
Exacerbating this problem is that consumers can’t even rely on saving money on fuel in the long run, since prices move so dramatically. A few months ago when the latest Jetta TDI came out, you could never recoup the purchase premium in fuel savings – it wouldn’t pencil out when diesel was 80-90% more expensive than gasoline. Now you can recoup it in..like…a month.
Even a consumer who WANTS to look past first costs can’t count on their numbers over time. That’s as big a deterrent as purchase price premium.
Europe is also a factor in the diesel/gas price balance. They tax diesel less and use it more (more diesel cars and less use of rail for transportation of goods). They export gasoline to the US.
The concept of total cost of ownership is difficult for most people to address.
Is diesel more expensive than gas? yes
Does it get better gas mileage than gas? yes
Are diesel repairs more expensive than gas? yes
Do diesel cars last longer than gas cars? yes
So let’s see, I’m paying more for gas but I’m getting better gas mileage and it’s going to cost me more to repair my car but then I can run it for more years and wring more out of my purchase price. So am I saving money? Probably but it’s not so evident.
In Canada, diesels are more widely accepted but there’s two reasons for that
1. For all those years that diesel was more than gas in the US, it was less than gas in Canada. That changed in 2008 and the current trend is similar to the US. So you could have your cake and eat it too. Many people who actually bought a diesel (as opposed to constantly talking about theoreticals),started a love affair with them.
2. There’s just too much damn land here so you need something that will be cheap to drive the 8-20 hours required to get from from one major city to the next.
I was seriously considering one before, but had hangups with VW reliability (not the engine itself but the car as a whole).
The reason Diesel is ‘cheaper’ now is because the weather is warmer (ie. no fuel oil needed by the houses in Eastern Canada and the US). Diesel will again be more expensive than gas come the fall when it gets cold again.
Couple more ideas about this:
~ Rail car loadings are down too. (about 20% under a year ago.) Thus lower train miles and diesel consumption. Add this to warm weather and reduced truck traffic cited above.
~ Diesel engines have 20:1 compression ratios so they can burn on compression alone. This necessitates that they be heavier (stronger) for a given displacement than a gasoline engine.
~ Diesel engines inject the fuel at high pressure into the cylinders. This requires greater attention to the machining of the injectors and to making sure that the fuel is clear of contaminants than in the case of gasoline engines.
~ The fact that diesel engines don’t have spark ignition systems and are more heavily built contributes to their greater longevity.
Diesel longevity can’t be taken for granted.
You can’t compare the old, low tolerance over engineered low pressure unfiltered smokers to the latest ultra refined, high tolerance, high pressure direct injected turbo diesels with complex multi catalyst, multistage exhaust systems.
I have been following clubtdi forums on the new 2009 clean TDI. Numerous turbo failure, clogged DPFs etc and they are new. Talk to me in 15 years and will see if they are any better than gas engines.
In 20 years I have never had an engine related failure in any of my gas cars most of my cars were old beaters when I got, the engine was still running fine when the left me. Usually the car falls apart around the engine, but the engine keeps going.
I know that a simple gas engine with no turbo is going to cost me a lot less in maintenance and it will be a fluke if the engine needs to be cracked open before the car is well beyond any state I want to use it in.
Kyle Schellenberg:Do diesel cars last longer than gas cars? yes
fincar1: The fact that diesel engines don’t have spark ignition systems and are more heavily built contributes to their greater longevity.
Objectively speaking, I have not come across a shred of evidence to support these opinions. Yes, way back in the seventies, Mercedes diesels were overbuilt. But modern automotive diesel engines are designed to the same longevity standards as gas engines. Only those specific components that have a higher stress are relatively stronger. But that is negated by the higher stress.
There are well documented examples of modern gas engines going 500-600k miles in commercial usage. That is well beyond the design life of automotive diesels, although some might last that long too. To the average owners, these numbers are totally meaningless.
As an employee of a company that operates 300+ vehicles in some 50 offices around the world I can say;
1. The hybrid vehicles are both more reliable and less expensive to own/operate (including a higher resale at end of lease).
2. The diesels are next, with excellent economy, very high reliability and a low TCO.
3. Leaving petrol/gas cars last….
The Europeans understand it. Wakey-wakey USA.
BTW, the global cost of diesel almost exactly tracks mining/construction/agriculture use, not rail traffic or heating/shipping oil fuels.
Paul Niedermeyer :
Objectively speaking, I have not come across a shred of evidence to support these opinions.
I don’t think it has anything to do with over/under engineering, it’s simply that you’re dumping lubricant into the chamber with each series of explosions. Less friction, less wear – seems simple to me.
Kyle Schellenberg: I don’t think it has anything to do with over/under engineering, it’s simply that you’re dumping lubricant into the chamber with each series of explosions. Less friction, less wear – seems simple to me.
That’s opinion, not the “shred of evidence” I was looking for. The reality is, in modern gas cars the fuel injection is so accurate that there is no extra unburned gas to wash down the cylinder walls. That might have been the case thirty years ago with chokes on carbs, but no longer.
Friends with European brand cars seem to spend considerably more time and money on car repairs than friends with Japanese brand cars. Even if diesels made economic sense, a Volkswagen, Mercedes, or Jeep diesel is an unattractive option in the US because of reliability concerns. College educated salaried workers work overtime and can’t afford to waste time on an unreliable car. Bottom line: Toyota and Honda don’t offer diesel engines in the US and they’re the benchmarks for retail sale passenger cars. If/when they decide the market will pay for diesel cars, other manufacturers will probably follow.
Yes sorry I wasn’t offering up evidence, I should have taken an excerpt from a different part of your comment.
I did a quick search and found some discussion on a tractor forum and this is definitely one of those age old questions that probably can’t be answered with 100% certainty.
One opinion (there’s that word again) I got was that although gas engines have the potential to have a long lifespan, they may be designed to meet ‘acceptable levels of engineering’ to match the production price and maintain profitability. Because gas cars are cheaper to buy and more common then they are treated more like a disposable commodity to be replaced when the owner is drawn to a newer model.
Diesel engines on the other hand have to be built to handle higher compression but designing them to be ‘just acceptable’ could have a more detrimental outcome on a failure so perhaps they are built up more than they need to be. They cite an example where in the 80s GM just modified a gas engine into a diesel and they immediately received a terrible reputation for reliability. Do diesel owners hang on to their cars for longer? I don’t know but if they spent more up front to get one they might. There’s also the underdog factor (I’ll show you that diesels rule!).
Another unrelated thought is that it’s the lower rpm that diesels tend to run at that saves the engine’s life.
Kyle,
I’ve absorbed all the arguments and assumptions over the decades. I’m not anti-diesel. But these observations and arguments are just the self-reinforcement that diesel owners use to justify their not-always economic decision to buy or own a diesel.
Modern automotive engines are now both designed and capable of attaining and exceeding 200-300k miles. Lots of gas (and diesels) surpass that with 400-600k miles. How many owners are going to actually run their cars that long? There is no difference in longevity anymore, like there once was. But diesel owners understandably want to hang on to the old myths, that are reluctant to die.
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God Bless America
“Just how the hell is anybody supposed to run a business when a crucial commodity price swings wildly all over the place?”
An excellent point. It is hard to believe, but government intervention to make prices more predictable might be just what the “free market” needs.
BTW, China’s government directly controls the pump price of gasoline there. Last year China was subsidizing gasoline heavily. Note to the those who float the idea that modern China is more capitalist than the US, it isn’t.
I’ve been driving diesel VWs now for 11 years and won’t buy another gas powered car as long as diesel passenger cars are available. TDI engines are supposedly designed for 10000 hours of life, which means about 500000 miles or so. I’m sure a modern gas engine could make it the same distance. But people get bored quickly with their vehicles so the longevity thing isn’t such a big deal these days. I bought the car with the intention of owning it for a long time, and I bought it with the knowledge that VW isn’t a great company, but the TDI is a pretty solid engine. And I wouldn’t have bought a TDI if tdiclub.com didn’t exist.
I love VW’s diesel engines and I accept that it might cost a bit more to run than a gas engine. However, I only change oil every 10000 miles (costs about $32 for oil/filter), then there’s a new $25 fuel filter every 20000 miles, and a $12 air filter every 40000 miles. The timing belt interval is every 100K, and that runs about $600 for parts and labor from my local TDI guru.
My injection pump did fail recently at 107000 miles and it did cost $1000 for a new pump and labor, but there are stories of expensive premature component failures with any brand of car. Plus Bosch made the IP, not VW.
I think the US will always be afraid of diesel engines. A lot of people don’t even know about them to begin with, and the people that might know about them still think of them as dirty dump truck engines. But as long as VW keeps importing them, I’ll be happy. I enjoy having my own private pump to fuel up at once a month.
The myths exist on both sides of the fence Paul. ;)
I generally am a self-reliant, DIY guy. I work on my own cars, I even drive them on my own home-made fuel. The only thing I’ve ever paid a mechanic to do on my TDI is change the timing belt, and that was only because the tools to do the job cost more than the job itself. So in seven years and 140,000 miles of usage, I’ve saved a lot of money on my choice of motive power.
I have nothing against gasoline. I own a lawn mower and an old Jaguar that run on the stuff. I just wish a lot of the myths about Diesel would die, if only so that I could choose something other than one model when it comes time to replace my current car. I love my Jetta, but I’d kill a few folks here to get some of the choices available across the pond.. say an Alfa Romeo Spider JTDM?
So here’s a myth about Diesel that comes up a lot: “The stuff that comes out of the tailpipe is REALLY bad for you.” In fact a commentator on the “London busses kill 3000 people a year” post from a few weeks back used the phrase ‘Diesel Kills”, I asked it then, and I’ll ask it now (because I never get a volunteer when I pose this challenge!)
You close your garage and sit inside your idling gasoline powered car. I’ll close my garage and sit in my idling Diesel. Let’s see who dies first.
I promise you it won’t be me. I might cough. My challenger on the other hand will pass out, and then die.
–chuck
Chuck, Interesting, because our nine year old Subaru Forester has only needed a timing belt as any repair of consequence. But these are anecdotal bits of information, hardly the basis for a conclusion.
The bad stuff in diesel fumes are the cancer-causing chemicals in the soot, not the carbon monoxide. That’s been all-too well documented, and the reason for particulate filters.
Carbon Monoxide from internal combustion engines becomes a problem in enclosed spaces, not outdoors. So your challenge is irrelevant regarding the tens of thousands of deaths scientifically attributed by many studies to diesel fumes in so many large cities around the globe. They’re dying from cancer and other problems caused by soot, not CO.
And even though diesels emit less of it, please Chuck, don’t go sit in the garage with your TDI running and the door closed – it might still well kill you. Diesel engines can emit up to 1200 ppm of CO, and even 667 ppm will cause half of your blood cells to…do things that won’t sustain life. OSHA’s limit for prolonged exposure to CO is 50 ppm. Would you want to gamble on beating that in your garage?
In terms of light duty (car) diesels, a VW engineer once told me that they engineer their diesels to withstand the forces/temperatures involved with the same tolerance factors as their petrol/gas engines.
Everything else being equal, that means they probably have about the same theoretical lifespan, and driving differences probably determine the rest.
As another example; the VW Golf TDi has the same driveshafts as the GTI because the torque is similar.
In terms of complexity, the singular advantage of diesel over petrol/gas was the largely absent electrical system. The electronics assisted diesels of today are just as, if not more complex, than their petrol/gas cousins.
I love to say it, “I told you so.” I think it was last summer?
Diesel haters said it was stupid to buy a diesel due to price of fuel, and now they change their tune to maintenance. Well, they may be correct about that, I don’t know, but I did know the price difference would go away because I asked some folks who would know, while using my brain to judge their case. (That last part is where journalists and politicians usually fail).
Wouldn’t you all like to know what the NY financial advisor we had over for brunch had to say about the chrysler BK?
I bet you would.
@TonyJZX :
the downside is much higher maintenance costs IN GENERAL
anything to do with the fueling system in diesels is often multiples of gasoline… eg. thousand dollar fuel pumps etc
If you compare high-tech diesels with low-tech gassers maybe… but modern gassers are direct injected and often turbocharged and/or supercharged… so they need exactly the same kind of kit (common rail fuel system with all the pumps and high-pressure piping, advanced injectors, turbochargers, intercoolers…)
@chuckgoolsbee :
I love my Jetta, but I’d kill a few folks here to get some of the choices available across the pond.. say an Alfa Romeo Spider JTDM?
Overweight bloatmobile on a GM Epsilon platform – but hell does it look fine.
@Kyle Schellenberg :
The concept of total cost of ownership is difficult for most people to address.
I own a calculator. Recommended.
In my case it was like that: (car purchase decision one year ago, BMW 1-series)
•MSRP of the diesel was 1550€ higher than that of the gas version
•Diesel was fun. Gasser was meh.
•Diesel on my test drive (lead footed) 5.8 l/100km (41 mpg), Gasser 9.0 l/100km (26 mpg).
•Diesel was actually a bit cheaper to lease, because used car buyers love them -> hold their value
•Diesel road tax: 308€/year. Gasser road tax: 135€/year
•Gas/diesel price roughly the same (+/- 10%)
Summary: Fixed cost about the same, (higher taxes for the diesel, higher depriciation for the gasser), diesel more fun, 55% higher fuel cost for the gasser with my driving style.
What do you think I drive now?
the kind of diesel motors i see in new cars/trucks these days are all direct injected, high pressure common rail turbos often VGT
this is all very modern and expensive technology
now some companies can contain this to some extent like Hyundai (and they have long warranties anyway) but I can detail some stuff like Nissan trucks that do need those $500 (you need six) injectors and $1,000 fuel pumps… i would be hesitant to keep these after warranty runs out
as far as i’ve seen most of the gasoline motors are not direct injection yet except for high end BMWs/Audis
so in summary, i’d have no problem with a diesel Hyundai with a 5 year warranty
i’d think again in say a medium sized truck with a 3 yr warranty
@TonyJZX :
the kind of diesel motors i see in new cars/trucks these days are all direct injected, high pressure common rail turbos often VGT
New gas motors are also common rail direct injected and many of them have VGT or twin-scroll turbos. GM, Volkswagen, BMW, Mercedes, Ford, Renault, PSA… they all seem to walk that route for gassers too.
Volkswagen’s gas-engine lineup for the European Golf includes 3 DI engines (1.4L turbo 125hp, 1.4L twincharged 160hp, 2.0L turbo 210 hp) and 2 IDI engines (1.4L NA 80hp, 1.6L NA 105hp)
The 1.6L NA engine will be replaced by a 1.2L DI turbo (105hp) later this year.
So it becomes pretty clear – NA IDI engines are becoming rare, even in economy cars.
so in summary, i’d have no problem with a diesel Hyundai with a 5 year warranty
Hyundai makes pretty good diesels these days.
PeteMoran
Thanks for that, I was hoping someone would post something based on engineering experience. The diesel truck engine programs I have worked on did indeed have longer life requirements for components (like for DV testing) than the gas engines for the same vehicle.
“I read that diesels are losing favor in europe in favor of the new more fuel efficient gas models.”
I doubt that’s going to happen. Our new and wonderful CO2 based taxation systems have caused many diesel cars to be much cheaper to buy and use than their gasoline counterparts, and diesel fuel is also cheaper in most places nowadays.
This is all very interesting to me, as my wife was recently smitten with the diesel bug. She thinks it may be time to replace her well liked 2004 Honda Civic Si (96k miles) with a new mount for commuting to work (~65 miles round trip). She wants something reliable, economical and fun to drive.
We recently test drove the 3 cars on her short list;
2009 Honda Insight EX, too focused on fuel economy, room, handling, braking and acceleration are no more then acceptable. Fun to drive ranking – poor.
2009 Honda Fit Sport with 5spd man. Amazing amount of room – and very usable with magic seats. Low beltline, like Hondas of old. Good handling and performance around town, but runs out of steam on the freeway at speeds over 60mph. Fun to drive ranking – good.
2009 Jetta TDI sedan with 6 spd man. and opt. 17″ wheels. Very comfortable, good stereo. Good ride and handling. Quick revving diesel and 6 speed makes for really good performance. Plenty of power for high speed merging and passing. Fun to drive ranking – two thumbs up!
We were both impressed the most by the VW, but the Fit is still a great alternative for people who like small hatchbacks with manual trannies, as my wife does! The key issues left to ponder are the issues discussed in this thread, diesel vs gas prices, maintenance costs, plus the $1300 federal tax refund. Issue #1 though – can someone spoiled by rock solid Honda reliability find happiness with a VW?
I have 2 diesel tractors and a diesel combine on my farm. Love them but for one thing: Don’t try to start them in cold weather.
Modern diesels are certified to start at 25 degrees below zero.
http://tdi.vw.com/a-vw-golf-tdi-gets-frozen-in-ice/
PN: Would you want to gamble on beating that in your garage?
If somebody with a gasoline engine took my bet I would. What’s the PPM of CO of canola oil compared to gasoline?
–chuck
I’d go out and buy a diesel car tomorrow if one was offered that fit my needs. All I can choose from are big, expensive trucks; big, expensive cars; and the “Hitler’s Revenge” brand of porky, monthly-trip-to-the-dealer cars (VW, this means you). I’d take a diesel smart, diesel i20, diesel Yaris, diesel Fit, even a Mini Cooper D any day of the week, but I can’t. I’m getting tired of waiting.
Chuck, Probably the same as any organic fuel burned in a diesel engine. And keep in mind, regular diesel fuel is an organic oil (dead plants). CO is a byproduct of (incomplete) combustion of any fuel, including wood, vegetable matter, etc. It all depends on the degree of incomplete combustion.
A German study showed that rapeseed (canola oil) burned in a diesel engine had more cancerous agents than straight diesel.
http://www.greencarcongress.com/2007/04/german_research.html
Despite the various pros (and cons) of using bio-diesel and vegie oil, it should not be assumed that the burning of them is intrinsically cleaner or safer than non-bio fuels.
As I’ve mentioned before on TTAC, the Best and Brightest need to brush up on their knowledge of oil refining. When you refine a barrel of crude you get some petrol, some kerosene (jet fuel), some diesel and some fuel oil and heavier by products. You can’t get 100% petrol or 100% diesel. A refinery can optimize for diesel fuel, but you will always get more gasoline from a barrel of crude than you will diesel. It’s a lighter product with less BTU’s. Since diesel has industrial uses which supeceed personal transportation in any shortage situation (oil embargo, etc.) you will likely see rationing of diesel long before that of gasoline. It’s a risky bet to go with diesel when any economic recovery will likely see massive inflation in that commodity long before gasoline.
When you refine a barrel of crude you get some petrol, some kerosene (jet fuel), some diesel and some fuel oil and heavier by products. You can’t get 100% petrol or 100% diesel. A refinery can optimize for diesel fuel, but you will always get more gasoline from a barrel of crude than you will diesel. It’s a lighter product with less BTU’s. Since diesel has industrial uses which supeceed personal transportation in any shortage situation (oil embargo, etc.) you will likely see rationing of diesel long before that of gasoline. It’s a risky bet to go with diesel when any economic recovery will likely see massive inflation in that commodity long before gasoline.
Thanks for that, well said.
Talking about burning diesel instead of gasoline is like arguing that we should eat chicken breasts and throw away the thighs.
Oil includes gasoline, diesel, jet fuel, asphalt, etc, and the smart thing to do would be to use oil efficiently, not to have an irrational consumption ratio based upon some fanboy love of a preferred fuel.
Most of a diesel’s superior fuel mileage, when measured on an mpg basis, is due to the specific gravity (BTU content) of the fuel. But if you look at a barrel of oil in the big picture, diesel is not more efficient than gasoline, it’s just different.
Diesel may have more energy per gallon, but it also has higher oil content per gallon, which explains most of the gain. Produce another gallon of diesel, and you lose more than a gallon of gas. It’s not an even tradeoff.
My exhaust smells like french fries Paul. I’ll die happy!
You guys are all way too serious, and taking me way too seriously.
I love my Diesel. I like making my own fuel (I have a batch drying as we speak, and another load of WVO going into the processor.) I get 50 MPG routinely without having to watch a star trek-like dash console telling me to annoy traffic behind me of the freeway. I haven’t spent a dime with a VW dealer service dept, as my TDI seems to have been built before siesta time, or maybe after, who knows?
Bottom line: I’d like to see greater choice of diesel powered cars in the USA, period. Right now you can count them on one hand and have most of your fingers left. That is not enough of a choice, or enough of a market to make judgements about.
–chuck
It’s worthwhile clarifying that in the refining process diesel is not just gas that has oil in it, it has a different molecular make up. The refining process distills the various parts from crude oil at various temperatures but gasoline only makes up 40% of that overall pie. Chemical processing (sounds earth-friendly) is used to extract more gasoline from diesel, due to demand.
So if shortfalls of diesel drive up prices, then gasoline is partially to blame due to its influence on the refining process. So in essence it’s kind of the chicken or the egg thing. If diesel became popular, then less gas would be extracted from diesel which would keep the price competitive.
A couple related links with purdy pictures:
http://science.howstuffworks.com/oil-refining2.htm
http://science.howstuffworks.com/oil-refining4.htm