With automakers under pressure to boost fuel efficiency, diesel engines are beginning to look like a good bet.
Diesel fuel offers approximately 10 percent more energy per volume than conventional gasoline. It also provides about 25 percent better fuel efficiency. Yes, dieselís long-chain hydrocarbons are more expensive to extract from a barrel of crude, and diesel engines are more costly to build, but these days, thatís mattering less and less.
As a result, automakers are more frequently looking to diesel engines. Two weeks ago, Chevrolet officially rolled out its compact Cruze Diesel. And earlier this year, Volkswagen showed off a diesel hybrid powertrain.
Weíve collected photos of recent entries in the diesel arena. From Audi and BMW to Chrysler and General Motors, we offer some of the best of past months.
Click on the photo below to start the slideshow.
A few weeks ago, Chevrolet rolled out the Cruze Diesel, said to be the first American-made diesel compact since the 1986 Chevette. The Cruze will be big on torque, offering 258 lb-ft at 2,000 rpm, compared to 150 lb-ft for the Cruzeís gasoline-burning version. (Source: Chevrolet)
In Europe the diesel has been a big player for a long time. Many improvements have been made and the emissions are very reasonable. There the driver has always been the much higher price of fuel. When I was there about ten years ago ir was already close to $8 per gallon. Thus the cars and engines were smaller. Lots of diesels, too. This has not abated.
The use of turbochargers on these cars is also something much more common in diesels as far as I can tell.
With the increasing CAFE standards, which are a good thing, the improvements in ICE vehicles need to be pushed hard. Cars like the XL1 show what can be done. Lighter weight and smaller, more efficient engines are key. That will be quite a culture shift here. When I was in England I had a couple of cars. One was a V6 Renault. It was a great car. I couldn't sell it when I left. No dealers wanted one (I was not buying a new car). I found no private buyer. I ended up giving it to our church. Compared to our cars in the US it was very frugal. Compared to what people were buying there, it was a hog. It even had an automatic.
Yes, naperlou, the diesel has been a big player in Europe for a long time. And for good reason, European diesels are wonderful engines. Also, there's been a real political push for diesel in Europe, using various types of fuel and tax incentives.
Thanks Charles for such an informative post, Some says that diesel engines are obselete these days however some says that they are the next upcomming engines . Deisel engines are inexpensive even expensive car owners have started to save the feul with diesel engines. Diesel engines have higher torque it helps in high traffic moving on minimal engine turnover.
However every technology has advantages and disadvantages. One disadvantage is this that it doesnot completely mix with the air and produces CH, NOX and carbon black during combustion process. This carbon black can be adjusted by the exhaust filter which is mounted between exhaust collector and catalalyst.
Once i read that there are two kinds of feuls , winter and summer feul depending upon the temperature of solidification.When the feul freezes the flush is unable to pump it out and thts the end where you cant do anything however there are solutions for this but in petrol there is no issue of freezing. In diesel engines are there is problem of noise and vibration as well.
No doubt these days diesel engine is becomming very popular but the question whether to buy a dieles engine car or petrol engine car is really very complex. According to me it varies with person to person usage .If ones usage in terms of milage is not that high then investing on diesel engine car is no worth it but if somes milage is too much than one should go for diesel engine car .
I know in the midwest itgets cold enough that quite often diesel engines are left running outside. If you turn them off, they will gel up and you're stuck. This may be something that needs to be worked on to make this all work. I know they have engine/tank heaters that can be used to help. But then you are using electricity to keep the vehicle operational.
It is true that gelling may occur at lower temperatures, but a few ounces of diesel fuel conditioner (Howe's Lubricator or similar) should mostly eliminate gelling. I know it gets bitterly cold in parts of Europe and unless we are talking about huge transport vehicles, it shouldn't pose too much of a problem. I do remember a long-haul trucker keeping a shallow barbecue pan, charcoal briquettes and charcoal lighter in his truck during runs to the North, just in case hard starting became an issue. Just start as you're going to barbecue, wait for nice hot coals to form, and then slide under the engine to warm up the oil, battery and fuel in the lines. The closed hood holds the heat for maximum effect! Otherwise, parking a passenger car in a garage, employs some kind of dark magic. One diesel vehicle at -30 outdoors and one -30 in a garage; the one in the garage will start much more easily.
I just drove through Belgium, Holland and Germany in a Ford Focus diesel, six speed with start-stop. I always insist on a diesel when I go to Europe. Unfortunately I didn't calculate my "gas mileage", but the driving was great. We could hear engine noise with the windows open from reflecting surfaces, but it was quiet inside otherwise and no "diesel smell". Didn't have too much high end power but kept up on the autobahns. The low speed torque was amazing.
The American anti-diesel mindset is ridiculous. I'm sure there are many to blame, starting with the politicians and oil companies.
Yes, Rob, big things are happening with diesels. And we can expect to see more. Diesel fuel injection is very high pressure and the fuel needs to be controlled very carefully. That control can be expnsive, but I think we're going to see the prices coming down. Also, control of nitrogen oxides in diesel exhasut can be tricky and costly, but I think we'll see those costs coming down, as well.
TJ, we had a Volkswagen Jetta TDI, which had several glow plugs which heated the fuel line prior to start-up. In theory there may have been a few seconds of delay prior to starting, but i never noticed it, and this was on a car kept outside during Maine winters!
The trend in trucking is conversion from diesel to natural gas, which is cheap, plentiful, and inherently the cleanest fossil fuel. Diesel exhaust contains fine particulates, which directly threaten public health, and diesel engine, fuel, and exhaust systems must be carefully maintained to keep NOx and soot emissions from skyrocketing. Unfortuantely, the state of California gives diesel cars a free pass on the biennial smog inspection program.
The good news is that diesel engines can run on various biofuels. Overall, I have to give diesel a very conditional thumb up.
"....the state of California gives diesel cars a free pass on the biennial smog inspection program." This is not true. Californians are penalized for owning and driving Diesel vehicles. Not only do they pay the highest prices for fuel than anywhere else in the country, they now have to pay about $75 annually for a 5 minute "smog check". All they do is visually verify that nothing has changed from the factory defaults. There is no emissions test. They don't measure anything. They are looking for modified intake and/or exhaust systems.
Oh, and another thing, fine particulates in Diesel exhaust (mostly carbon) are much heavier than air, quickly settling out. I hardly call this "directly threaten public health". A much bigger risk to your health would be simply driving a car.
Finally, I would challenge the assertion by the author that "diesel's long-chain hydrocarbons are more expensive to extract from a barrel of crude". Oil comes out of the ground as long chained hydrocarbon molecules. Heavy fuels, such as Diesel, are some of the easier to get and least refined products (read cheaper) from crude oil. Gasoline, on the other hand, is farther up the distillation column so there is less of it in a barrel of crude. One of the added (and more expensive) processes is sending longer hydrocarbon chains into a cracker so they can break them into smaller hydrocarbon chains (like gasoline). Gallon for gallon, refining and storage costs for Diesel fuel should be considerable less than gasoline.
"Finally, I would challenge the assertion by the author that "diesel's long-chain hydrocarbons are more expensive to extract from a barrel of crude"."
YES!! I sent a good deal of time studying fractional distillation, and I shake my head in wonder every time this argument is trotted out. I guess, like everything else, they've got the distillation towers turned upside down...
The price of Diesel in the United States is higher than gasoline these days for two reasons; 1) The Federal excise tax for on-highway diesel fuel of 24.4 cents/gallon is 6 cents per gallon higher than the gasoline tax, 2) The worldwide demand for diesel fuel is greater than in the past and the refinery capabilities have not kept pace with demand.
Diesel is a lower order distallate than gasoline which allows us to extract MORE diesel fuel from a barrel of oil than gasoline. With a "normal" maarketplace diesel would still be significantly cheaper than gas. When government intervines in the marketplace distortions occur (i.e, regulations on refineries making it not cost effective to open new ones and punative taxes on diesel.
Diesel is a superior motor fuel in nearly every respect now that there are new chemical treatment systems that can virtually elliminate soot. Natural gas is cleaner, but we have yet to see the potential issues related to explosions and fires in crashes. Natural gas does not have near the energy density that diesel has. Hopefully technology with help mitigate the down side of compressed natural gas as a motor fuel.
We all need to keep in mind our basic physics and chemistry - energy density is a key to efficient production of power - whether we are talking about motive power or electric generation. If we didn't have fosil fuels we would have to invent them - they are just that good at powering our modern society.
God comment but where is second reason for more expensive Diesel fuel in the USA: this is big oil monopoly. Diesel fues is cheaper everywhere except in the USA.
Desig news staf: Where is revulutionary Diesel engine from Mazda? This engine is used in new excellent MAZDA 6, it features lowest compression ratio of any Diesel engine of 14:1, it is extremelly fuel efficient and does not require exhaust urea treatment. You missed-ignored one of the most important Diesel engine development news regarding MAZAD skyactive Diesel. Very superficial article.
"Big oil" would love to produce more diesel since they have the potential for higher profits (less processing for a more potent fuel), but since it is a tightly regulated environment they stick with the mix they have today. For a long time it has been public policy in the US to discourage diesel use (hence the higher taxes than gasoline and the regulatory preferences for gas). That is how we got to where we are. The public policy is not changing, so I would not expect to see any changes in behavior from the oil companies. The EPA has strict guidelines on the mix of motorfuels rigt down to how much of what additives are required on a seasonal basis. This is NOT a free market where some "Big Oil" cabal can do what they want to meet customer demand or their own selfish profit needs
There's a a lot of debate on the site about the availability and processing of diesel fuel. This is a contentious subject, with a lot of valid opinions on both sides. Here's what David Cole, founder of the Center for Automotive Research, former head of automotive engineering at the University of Michigan, a noted expert in engine design and the auto industry's premier consultant for the past 30 years, told us: "A barrel of crude has dozens of different hydrocarbons. Diesel fuel uses longer-chain hydrocarbons. You need those for auto-ignition. But it's hard to make, because you only have so much of that in a barrel of crude. It's easier to break it up into lighter hydrocarbons than it is to create long chains from the shorter ones. When you tamper with the mix and say, 'We need a lot more diesel,' you have to refine a lot more fuel. So it's important to keep a balance between the two."
Charles, thanks for the additional technical insight about diesel fuel. One other concern is that if it does become much more popular, the price will rise a whole lot, just because it can. And then there is till the concern about servicing the engines, which certainly are more complexed and more highly stressed in several areas. So it will be valuable to think out all of the secondary and tertiary effects of a larger percentage of vehicles becoming diesels.
Definetly deisel engine will provide more fuel effieciency for engines but it has many other consequences that we have to deal with, if diesel engine cars go into mass production. Like the higher price of diesel, if its demand gets high. Not that it is already less expensive. Other than that, as mentioned in a previous comment that it will also have more adverse effect on the environment due to the emissions of some fine particles in air.
Certainly makes a person doubtful of this decision.
Being in the midwest I can tell you there are lots of biodiesel plants which produce diesel fuel from soybeans. I don't know the details of their profitablity, but I can tell you they must be doing something right because they are still open. Of course, it could be due to government subsidies.
Really informative post Charles. My only experience with a diesel was not a very good one but, that was about 25 years ago AND, it was a used car. It's very obvious from your slides; the technology has certainly come a long way. My diesel was a smoking machine and tough to start on cold mornings. I'm sure the more recent engines perform in a competitive fashion compared with "standard" fuel. I will have to say I'm a fan of natural gas as a viable alternative (or complement) to gasoline. I think it might be the "fuel of the future". Again, great post.
A half century ago, cars were still built by people, not robots. Even on some of the countryís longest assembly lines, human workers installed windows, doors, hoods, engines, windshields, and batteries, with no robotic aid.
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