Does Real-World MPG Matter?

[darrelld]

http://www.greencarreports.com/news/1083331_diesel-vs-small-turbo-gas-engines-does-real-world-mpg-matter

 

As fuel efficiency standards tighten continuously between now and 2025, buyers will have more powertrain options to chose from.

And many have suggested there's a battle coming among smaller gasoline engines, diesels, and hybrids.

 

If so, we hope that buyers will do the research to look at the real-world fuel savings of each alternative--and NOT just the EPA ratings.

Edited April 12, 2013 by darrelld

[SnowStorm]

This article (and links) leave a lot to be desired.

1. They start with "we hope buyers will do the research...".  You are then pointed to EPA Your MPG figures and Fuelly.  So I did the research.
   38.5 for 2013 C-Max on EPA
   37.4 for 2009-2013 VW Sportwagon Auto on EPA
   37.8 for 2013 C-Max on Fuelly
   37.2 for 2009-2013 VW Sportwagon Auto onFuelly
   C-Max wins.
2. They say that diesels "...may thrive under hard use--especially in frequent high-speed highway use."  Interstate at 65 mph is not "hard use".  It only takes about 15 to 20 HP to push a car at that speed.  Wouldn't "hard use" mean at least 50% capacity of the engine?  Seen many 40 HP cars lately?  The whole statement is rather meaningless anyway - appears to be thrown in to make diesels "sound good".
3. Then they say that "the newest hybrids don't come anywhere near their EPA ratings" followed by a snide remark directed at Ford.  This is true but why is it twisted to sound like the Ford hybrids are "bad"?  The "research" they had me do showed the hybrid is better (if only by a slight margin).  You could rather say that the Fords EPA ratings exceed the real world averages (which are already excellent) and go off and fuss at the EPA rating system.  Ford can't change the EPA numbers!  The discrepancy is because the Ford hybrids are a better design than what existed before.  The EPA tests aren't calibrated for hybrids that can run on electric power only up to 62 mph.  See more on this subject at my post under this topic:
   http://fordcmaxhybridforum.com/index.php?/topic/1523-treehugger-getting-to-the-bottom-of-fords-hybrid-fuel-economy-controversy/
4. A linked 2009 article claims that a trip that gave 41 mpg confirms reports that the EPA rating of 30/41 mpg is "far too low".  (This was a "highway" trip from Atlanta to Amicalola Falls State Park.)  41 versus 41 - I don't get it.
5. At the end they act like the $0.40 per gallon extra cost for diesel is no big deal.
6. Nor do they point out that replacing timing belts on the VW adds another $0.45 per gallon equivalent (1.1 cents / mile) to your operating costs.
   (The C-Max has a chain.)

Now I think diesels are great technology.  But the money needed to operate the car long term is what counts.  If diesel fuel didn't cost more, I would be all for a diesel hybrid.  Best of both worlds.