The Case for Diesel: Clean, Efficient, Fast Cars (Hybrids Beware!)

Popular Mechanics ^ | 30 Dec 07 | Ben Hewitt

[saganite]

Merging with northbound traffic on Interstate 75 just outside Auburn Hills, Mich., I punch the accelerator, quickly swing left into the passing lane and pull forcefully ahead of the cars around me. In any other ride, on any other gray morning, it’d be just another Interstate moment. But this rush hour, I’m behind the wheel of a preproduction 2009 Volkswagen Jetta, which is powered by a 2.0-liter turbo-charged, direct-injected diesel engine that, even as I leave the speed limit in tatters, is averaging nearly 50 mpg. Equally important, what’s coming out of the tailpipe is no dirtier than the emissions from the 35-mpg econoboxes I can now see in my rearview mirror. Speed, fuel efficiency and minimal emissions? These aren’t characteristics usually associated with diesel-powered vehicles. But they will be.

Most Americans have a bad impression of diesel cars. We think of them as loud, hard to start and foul-smelling. We sneer at them for lacking the get-up-and-go of their gasoline-powered cousins. And we dislike them for their perceived environmental sins, chiefly the polluting brew of sulfur and nitrogen compounds that they emit into the atmosphere. All those complaints were fair a generation ago, when the twin energy crises of the 1970s propelled diesels into national popularity and kept them there for a decade. Back then, many drivers ignored diesel’s faults, or were unaware of them, because diesel cars ran 30 percent farther on a gallon of fuel than similar gasoline-powered cars. It felt savvy to buy a diesel, even daring. Then fuel prices dropped in the mid-1980s, and drivers abandoned their clattering, odoriferous fuel sippers. They went back to gasoline.

Today, diesel powertrains are on the map again, for both car manufacturers and efficiency-minded drivers. The technology could be here to stay, even if fuel prices (improbably) decline. .

[org.whodat]

Oops,

In the simplest terms I would call that much to do about nothing.

[saganite]

They have passed laws requiring new emmisions standards for Diesels and Kali standards are even tougher. Presumably these cars meet those standards.

[sausageseller]

Diesel engine will last twice as long with fewer repairs. Seems several thousand more would have been a good choice.

BTW I have a Dodge D350 with a Cummings, and over 200,000miles. Never had a wrench on the motor.

[org.whodat]

Here in CA

In the real world, people are not screwed as badly on taxes as in CA.

[B Knotts]

Propane is not much of an alternative fuel.

Try running vegetable oil in a spark ignition engine.

[org.whodat]

You have to add a plug to get it burn Propane.

No it will run fine with a mixture of propane and diesel. And for your education the first diesels ran off of coal dust.

[Paladin2]

Depends on how long you idle and how much you use your brakes. For highway driving the Diesel is much simpler. Around town? Hybrid makes more sense until batteries can store more energy per unit volume and mass.

[saganite]

If a Diesel already gets 40 to 50 mpg why bother with the expense and complexity of batteries and electric motors? All that stuff necessary to make a car a hybrid adds thousands to the cost (and the cost of environmental cleanup) during the life cycle of the car. In fact, you will never achieve payback over the lifetime of your electric hybrid.

[popdonnelly]

The problem is that the enviros view the internal combustion engine as a Doomsday device. And too many politicians are beholden to the enviros.

[wrench]

“The diesel is the great grandfather of the jet engine.

Explanation please.”

The idea of jet engine combustion originated in the diesel design. Both engines are unthrottled, and take in a full charge of air continuously. The air is compressed, and fuel is injected into the superheated (by compression) air resulting in combustion. Power is increased by injecting more fuel, intake air is unthrottled.

Turbocharged diesel design can lower the compression ratio as their turbo boost is increased. Taken to extream, the turbocharger becomes dominant, and the piston becomes immovable, resulting in a burner can instead of a compressiion cylinder containing a movable piston.

Keep upping the size of the turbocharger and size of the burner cans, and you increase the thrust of the engine exhaust. Shaft power can be tapped off the turbo shaft if need be.

[saganite]

You might find this article on LED’s interesting.

http://news.bbc.co.uk/2/hi/uk_news/scotland/glasgow_and_west/7162606.stm

[steve86]

Here in CA, diesel has commonly been $0.30 higher than gas at the pump.

Here in Washington, 55 cents or more (compared to 87 octane gasoline).

[Eric in the Ozarks]

Diesel fuel is about $.30-$.40 cpg higher in the Midwest, too. When I worked for a major oil company only a few years ago, we were always long of N2 and couldn’t find enough homes for all that we made. One month, because we had such a huge store of distillate, we actually ran our own oil in the refinery crude charge to make gasoline.

[shorty_harris]

Watch Congress come up with a way to further handicap diesels.

Well, I'm sure California will show them how...

[Alter Kaker]

But that's only because they're loud, hard to start, and foul-smelling.

Wrong. I drive a sporty Alfa Romeo diesel, and it's quiet, easy to start and smells just fine. Also, it moves like a bat out of hell and gets 35 mpg.

[popdonnelly]

Fact is, we’ve made enormous strides in both fuel efficiency and emissions over the last thirty years. But the enviros are still making the political argument that we’re destroying the planet.

[Hawthorn]

> If a Diesel already gets 40 to 50 mpg why bother with the expense and complexity of batteries and electric motors? All that stuff necessary to make a car a hybrid adds thousands to the cost (and the cost of environmental cleanup) during the life cycle of the car. In fact, you will never achieve payback over the lifetime of your electric hybrid. <

Then it looks to me as if the matter hinges primarily on the cost/efficiency of batteries. If the costs of batteries decline enough, or if their efficiencies increase enough, or both, then the diesel hybrid well might become a very attractive option. But as things stand today, I understand and accept your analysis.

[saganite]

Well, the enviros have an end game in mind and it doesn’t involve personal transportation of any kind. No matter how great the strides they will continue to move the goalposts.

[blau993]

Thanks for the article. I’m looking to replace an old SUV and am looking at a Mercedes diesel SUV, among others. This is an interesting read.

[saganite]

There was an article posted here last week I think where researchers claim to have achieved a tenfold increase in battery capacity. If that’s so and it can be adapted for vehicle use then all bets are off.