Perspective: Diesel is no longer a dirty word

You know the list: Ethanol, electric, biodiesel, compressed natural gas, hydrogen, hydrogen fuel cell and hybrid. They are the Seven Horsemen of the Automotive Apocalypse, nee The End of Cheap Oil--the harbingers of a time when powering cars will be complicated.

We probably have about 50 years of "cheap" oil left. By cheap oil, I mean oil that's cheap enough--plentiful enough, really--to be used in private cars. After that, its use will likely be restricted to commercial transportation, military applications and emergency vehicles. Maybe licensed, classic-car collectors will be allowed to buy 1,000 gallons a year, but other than that, unregulated consumption of oil and its prized distillate, gasoline, just isn't fathomable.

Aside from a few Prius owners, we want cars that save us money, don't look stupid, don't require us to learn new procedures for auto ownership, and don't cost more than what we drive today.

But that's off in the distance. Most people reading this today will have had their driver's license yanked due to senility long before such restrictions kick in. We are instead concerned about how much we spend today on a gallon of gas, not when it will run out, how much it pollutes or what kind of global tensions it creates. Aside from a few Prius owners, we want cars that save us money, don't look stupid, don't require us to learn new procedures for auto ownership, and don't cost more than what we drive today.

Bottom line: You and I stand in the way of advanced powertrain vehicles, just as much as any oil company conspiracy or automaker's backwardness. We stand in the way by virtue of our attitudes, as evidenced by our responses to the carmakers' armies of market researchers who have relentlessly probed us. That's why I get excited about diesels. They can make a big difference and they aren't strange.

In fact, diesels are hot. The new Golf TDI turbo diesel I just hammered across the French countryside was imminently fun and livable. After crossing the Swiss frontier into Geneva, I immediately looked into buying one and shipping it home. Luckily they couldn't do that for me as I would have had a nasty surprise when I tried to register it back in California. (More on that later.)

I was left with memories of great, lugubrious gobs of torque coupled with a fuel-tank range that was almost goofy. In four days of hare-and-hound driving, I was never the one slowing traffic: The Golf was always willing to hunker down its little rump and breathlessly keep pace with anything else on the road.

And that Golf TDI was not alone. Car and Driver is smitten with BMW's 330d, the turbo diesel version of the familiar 330i gas engine sedan. The reviewers laud it because it "feels faster than a 330i" (its gas-powered sibling), gets 44 percent better mileage, and has so much midrange torque that you practically forget about downshifts.

Ditto for the Jaguar XJ with the brand new 2.7 Diesel V6 powertrain, which delighted The Times of London with its fabulous torque and fuel economy around 35 mpg--in a big Jag, no less.

See the pattern? Economy, sporty, luxury. Diesel is proving to be a winner in all kinds of cars. But there are two hurdles for diesels in the United States: image and emissions.

This is a formula for a car that can pull stumps out of the ground in almost every driving scenario and use damn little fuel doing it.

The former is due largely to General Motors' miserable forays into diesel engines in the late '70s and early '80s. As I recall, these were basically re-engineered gas engines that came apart in all kinds of unpleasant ways. Even if the cam stayed in the block, they were horrible, noisy, filthy things that made a mockery of the big, supposedly elegant cars into which they were shoved. (At least GM made a run at it; Ford mostly piddled around with oddities like the Lincoln Mark VII with optional BMW Turbo diesel engine.)

With its diesel clunkers, GM single-handedly undid all Mercedes and Volkswagen had accomplished with their excellent diesels in the S-Class and the Golf. Those well-received oil-burners from Germany weren't as fast or quiet as our modern common rail, turbo diesels today, but they were well-built. You have a good chance of pulling up next to one at a stoplight today.

The other problem with diesels is nitrogen-oxide emissions, the unburned particulate exhaust that is perhaps the greatest contributor to visible smog. This is the diesel's dirty Achilles' heel. These engines run at high compression ratios and therefore high temperatures, which creates a high level of nitrogen oxide from the sulfur in diesel fuel. As of 2007, new U.S. emissions laws will actually be a lot stricter than European regulations, which means that even if a carmaker has a thriving diesel lineup over there, it won't be certifiable for sale in the U.S.--not even close.

Here's how we'll sort this out: First, the new stringent diesel sulfur regulations will make diesel fuel 33 times cleaner than it is today and must be used in all car models beginning with 2007. Then, a combination of particulate filters already being used on European diesel exhaust systems, along with an "after-scrubber" technology (BMW has been vocal about urea injection, while Mercedes offers their BlueTec system) cleans the exhaust even further. We should see 50-state-approved diesel cars starting as soon as the 2008 model year, and really kicking in through the end of this decade.

Frankly, the public perception feels like a bigger problem than the emissions issue.

Which brings me to the last and perhaps most appealing prospect: the diesel hybrid. Coupling a diesel with an electric motor makes an accepted "alternative" engine even better. A diesel can be an even smaller and lighter partner to the electric motor while continuing a torque-fest beyond its optimal RPM range.

This is a formula for a car that can pull stumps out of the ground in almost every driving scenario and use damn little fuel doing it. Hermann Scholl, chairman of Robert Bosch, fully expects diesel hybrids in the U.S. before the end of the decade.

The stinky, noisy, gutless diesel of the past is gone. Today it's an engine that can offer roughly 45 percent better fuel economy as a drop-in replacement for a gasoline equivalent while offering much more of the kind of torque that makes real-world driving enjoyable. We have a fueling infrastructure in place that can be easily tilted more toward diesel, and there's no learning curve when you drive a diesel car: Turn the key and press the pedal on the right.

Kick in the diesel hybrids in a few years, and we're really onto something. No, diesels don't move us off oil, but they do use less of it and reduce refining effort, which has proved to be almost as big of a factor in gas prices as the cost of crude. And I'm not even factoring in the use of biodiesel.

The modern diesel engine is a path to frugality that doesn't have to feel like one, a form of motive power that is a joy to drive with, and can be cleaned up and ready in the very near future. The biggest problem is its image.

Biography
Brian Cooley is an editor at large at CNET.

More Perspectives

[rainman09]

Diesel engine's mileage

Diesel engines get better mileage because they the fuel itself consist of longer chain hydrocarbons than the normal gasoline. The longer chain means that it is denser than gasoline at the same temperature making it pack more energy per gallon. Does it make diesel engines more efficient? Maybe, but let's not delude ourselves by saying that we get better mileage, but then go on and actually release more CO2 into the atmosphere.

[gnwiii]

There is more to the story

Your analysis is appropriate to an engine running at full output -- a small fraction of the time in many engine applications.

Think about a gas engine running well below peak output. For each power stroke, the entire combustion chamber must be filled with a certain air-fuel ratio. With a diesel, you fill the chamber with air and add just the fuel required to get the required power. This is why some gas engines do tricks like shutting off some cylinders when power demand is low. Diesel also has lower "shrinkage" and lower transportation costs per BTU in the distribution system and uses a simpler refining process that takes less energy. Less CO2 is produced using diesel in typical driving cycles and in producing and distributing diesel fuel from fossil sources.

For colder climate, the biggest drawback to driving a diesel is the limited waste heat they produce, which means they take longer to warm up and are less able to keep the passengers warm than a comparable gas engine in cold weather.

[alhart4cnet]

Diesel fuel is safer

The lower volatility of diesel fuel presents a much lower explosive
hazard in a collision. With a partially empty gasoline tank, you are
riding around with a fuel-air bomb.

Rediculous

"We probably have about 50 years of "cheap" oil left. By cheap oil, I mean oil that's cheap enough--plentiful enough, really--to be used in private cars. After that, its use will likely be restricted to commercial transportation, military applications and emergency vehicles. Maybe licensed, classic-car collectors will be allowed to buy 1,000 gallons a year, but other than that, unregulated consumption of oil and its prized distillate, gasoline, just isn't fathomable."

That whole paragraph is just plain stupid. Another self-appointed media imbicile going off about something he really doesnt understand.

First, if anything, its exactly the commercial, emergency, and military vehicles THAT WILL SWITCH TO ALTERNATIVES FIRST. They can do that because they are fleet vehicles which dont depend on a commercial distribution network.

Second, you're ignoring the 3 trillion barrels of oil in shale and tar form in north america that will eventually start flowing.

Third, the notion that we'll just 'run out' and all of a sudden find ourselves without oil makes no sense (if one understands the most basic of economic principles, that is, something admittedly you dont expect from journos nowadays). As oil gets more expensive, more people will move to alternatives. It will not be an overnight event. It will be a decades long process. The only way government rationing will come into place is if 1) there's a international blockage of sorts over a short period and 2) we have retarded politicians who think rationing is a good solution to the shortage (after all, it worked so well in the 70s).

[eddennis]

I would remind the writer that diesel engines can operate on fuel other than petroleum based diesel fuel. As long as we have the ability to make alcohol we will have fuel. I am afraid the writer suffers from having swallowed the kool aid offered by the liberal establishment. His kind of thinking will doom us all. The fact is Hydrogen power and electric power only offer extremely expensive alternatives to technology that currently exist. A hybrid diesel electric power plant offers almost immediate relief from petroleum dependency. Think about a Pyrus that delivers 35% better mileage and runs off corn oil. This technology exist right now! We don't have to wait on oil to run out or get scarce to spur product development.

[Squashman2]

Diesel Mini Van

I am just waiting for a Diesel powered MiniVan. My freestar barely gets 20mpg. A Hybrid Diesle mini-van would be nice as well.

[Hardrada]

There already is one

1982 VW Vanagon diesels. 30+ MPG in city driving.

[gnwiii]

You waited too long!

I drive a 1993 VW Eurovan with a 5-cyl diesel.
Nothing comparable is sold in N. America today -- maybe if fuel taxes in N.A. were raised to European levels and used to fund a sensible mix of public transport and roads rather than putting everything into very long 6-lane parking lots the N.A. market would offer sensible alternatives.

[ugh333]

my next car/truck will be a diesel electric hybrid

I drive a 2003 VW Beetle and I try to keep at least 20% biodiesel in it. Biodiesel goes a long way to cleaning up the diesel emissions. NOx is a problem, but with the filters mentioned in this article we can fix that problem. Diesel engines last a LONG time (500k-1M miles) vs. gas engines. They have much better resell value also, just compare them to gas vehicles on cars.com.

[ugh333]

diesels are fine in california

the author of this article forgot to get back to the diesels in california issue. i live in california and drive my diesel beetle all over. you can't by a new diesel car here, but you can buy a new truck. you can also buy a used diesel vehicle in cali, but it has to have more than 8500 miles on it. You can also buy out of state and run up the 8500 miles before registering. it's a silly law aimed at the old dirty diesels. and btw, the clean diesel was supposed to be required this year, but it was bumped back. let's make sure that it doesn't get bumped again in 2007...

[richlo]

Middle America Legislators Hate It!

Unfortunately, politicians will delay this by a few years. There is no such thing as a Ethanol-Diesel blend - and that would significantly cut back on the sales of corn to make ethanol, thus angering a very powerful block of voters. They will throw every barrier they can into delaying an even otherwise faster take-up rate for diesel.

[C.Schroeder]

Maybe not

Last I heard, ethanol demand currently exceeds the supply, even with new capacity slated to come on-line in the next year. This is because the oil refiners need more ethanol now to replace other gasoline additive(s) they used to use to reduce emissions. I don't think an ethanol-diesel blend is even an issue at this point.

[BigJohn13]

Not entirely true..

We could be using Bio-Diesel which is already being used..
Here's a quick paste of what it is..

http://www.biodiesel.org/pdf_files/fuelfactsheets/
CommonlyAsked.PDF

Technical Definition: Biodiesel, n?a fuel composed of mono-
alkyl esters of long chain fatty acids derived from vegetable oils
or animal fats, designated B100, and meeting the requirements
of ASTM (American Society for Testing & Materials) D 6751.

[weconnors07]

Biodiesel Complements Ethanol Production

I know I am responding months later, but I just discovered this thread, and have this to share. The high price of corn in the US (caused by demand for corn for tax-break-induced production of ethanol) will drive up corn production, but there is a limit to this. Crops need to be rotated. Soybeans are a great rotation crop for corn. More corn = more soybeans. What will farmers do with all the soybeans? Answer: biodiesel. Once Midwestern Congressmen figure this out, there will be biodiesel production tax incentives to raise the price of soybeans, and there will be a lot of biodiesel available on the market.

[eddennis]

Why would politicians oppose this - have you ever heard of "corn oil" - Mazola? Farmers will love this because corn oil is one tenth the cost to produce compared to ethanol. The process pollutes nothing and could in fact be done in street corner factories.

[louisp123]

very fast diesel in fact

Being a young car enthusiast stuck in a world of modified "high performance" cars ranging from blue burning hatchbacks to gas feining v8's, I am proud to say that my 2003 Golf TDi is a strong contender. In terms of "american acceleration", it does not set any records on the local drag strip although in real life driving conditions it does set its mark. With the north american offered 1.9tdi 90hp (being the least potent of a array of 1.9tdi offered from vw)and 700 dollars in your pocket, anyone can easily push out 130+hp and 250++bl-ft in torque. That is enough to get anyone into trouble in the mountain twisties or even on the highways, fast. Refering back to the "silly" low consumption of gas, this 1.8T comparable power at 1000km/tank and bio-diesel compatable makes it something of a conversation piece at the local meets. Just thought I would give my share of support to the subject and to say that even though the real performance of diesel engines (in passenger cars, not trucks) lies in europe, there is still plenty of fun to be had with affordable VW tdi's right here in North America.

[tonybelding]

Horsemen of the Automotive Apocalypse

"Aside from a few Prius owners, we want cars that save us
money, don't look stupid, don't require us to learn new
procedures for auto ownership, and don't cost more than what
we drive today."

Aside from cost (which is more of a volume manufacturing issue
than a technological one), electric cars and plug-in hybrids could
meet those requirements today. Or I should say. . . That is
assuming you aren't daunted by "new procedures for auto
ownership" like not having to stop at the gas station anymore. I
think most people are flexible enough to adapt to that.

I just can't figure out why alternative vehicles get lumped in with
the Horsemen of the Apocalypse here. What does the author
think diesel engines are saving us from? Are they going to
rescue me from the pain and anguish of stopping at the biofuel
pump instead of the regular gasoline pump, or stave off the
human tragedy of taking three seconds to plug in my electric car
when I get home? Is my tiny consumer's brain supposed to
become hopelessly befuddled when "powering cars will be
complicated" because they don't all run on gasoline anymore? I
don't think so.

[m.o.t.u.]

This is a good sign

I assume most of the respondents to this article are living within the U.S. As the largest consumer of fossil fuels on OUR planet, I congratulate you and your Legislature for more strident emmission controls, and a growing awareness of fossil fuel consumption. You are the biggest consumers, so you should be able to make the biggest reductions. The developing economies need good examples to follow.

[alek_nedic]

largest consumer

http://www.analogstereo.com/mercedes_clk_class_owners_manual.htm