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Diesel v. Hybrid incentives duke it out in D.C.
5/03/05

Hi everyone, Don Anair CA vehicles analyst with my first hybridblog.  Not to be confused with my DC colleague Don MacKenzie, who posted the first hybridblog and absconded with the screen name "Don," I'm going to use the monicker "Sharkey" from here on in.

Now, the House eliminated credits for hybrid vehicles in the energy bill, but supports credits for diesel vehicles in the Energy Bill they just passed… and now, even the president backs polluting consumer incentives by giving taxpayer dollars to diesel vehicles, taking us a step backwards on childhood asthma and lung disease in our elderly.

The Diesel Technology Forum (DTF), an industry trade group, was delighted to hear the president’s support for diesel vehicles on Wednesday.  On Thursday, DTF even had a "ride and drive" event on Capitol Hill touting their "clean, quite, and fun" to drive diesel vehicles.  Clean? Diesel vehicles have certainly become cleaner over the years because of stronger emission standards, but they are still far from the cleanest vehicles on the road today.  For example, take the diesel VW Jetta.  This vehicle emits about 44 times more smog-forming nitrogen oxide emissions and between 4 and 8 times more toxic diesel particulate emissions (that's soot, folks) than a comparable Toyota Corolla . I don’t know about you, but I wouldn’t call that clean.
 
True, I’m making a comparison of today’s vehicles and not accounting for the fact that diesel vehicles will have to meet the same set of emission standards as gasoline cars by 2009.  But the structure of these standards will allow some vehicles to emit a lot more pollution than the average.  Many of today’s conventional vehicles are several times cleaner than the average vehicle under new tailpipe standards.  Not so with diesels.  Diesels have a ways to go to even meet the average standard, never mind getting cleaner than average.  If diesel vehicles are unable to meet progressively tighter emission standards, future progress in protecting public health may stall. In fact, the energy bill in the House could make this prospect a reality by encouraging the sale of diesels that emit as much as 10 times more smog forming pollutants than some of the hybrids already on the road.

So what about fuel economy benefits of diesel vehicles?  Glad you asked.

Widespread introduction of diesel cars and trucks is sometimes heralded as the solution to reducing petroleum consumption in the U.S.  In fact, this promise is often overstated. As our report, The Diesel Dilemma, shows while diesels may have a role to play, a diesel-only approach to petroleum reduction could result in greater costs to consumers than utilizing more efficient gasoline vehicles for achieving equivalent petroleum reductions. 

Diesel vehicles might go 30 to 40 percent farther on a gallon of diesel, but that’s not the whole story.  Diesel fuel actually contains more energy per gallon than gasoline and producing each gallon of diesel requires 10- 25 percent more petroleum and results in 12-18 percent more heat-trapping gas emission than a gallon of gasoline—this takes a big chunk out of diesel’s commonly quoted benefits. 

Let’s go back to the VW Jetta/Toyota Corolla comparison again.  Even though the diesel Jetta receives better fuel economy numbers than the Corolla, they emit the same amount of heat-trapping CO2 emissions.  And to top it off, the Corolla does 0 to 60 in less than 10 seconds, a couple seconds faster than the VW’s 11.6 seconds. Go figure.

Add in the high up-front cost of diesel engines and emission controls and diesel vehicles could become a more costly approach to petroleum reduction than improved gasoline vehicles.  And remember, hybrid technology does something that diesel engines alone will never do - serve as a technological stepping-stone to fuel cell vehicles.   

If performance based incentives are going to include diesel engines, they must also provide the same benefits to other conventional vehicle technologies and must require that the vehicles meet or beat the tailpipe emissions standards for the average new car. 

Providing incentives to ONLY diesel vehicles, especially without adequate performance criteria for tailpipe pollutants, is a misguided approach and forces an unnecessary tradeoff between fuel economy and smog or toxic tailpipe emissions.  Those problems are especially glaring in contrast to the CLEAR ACT approach David talked about in the last post.

Posted by: Sharkey 5/03/05

Original post and comments can be found on Hybridblog.org.