TreeHugger - Getting to the bottom of Ford's hybrid fuel economy controversy

[ecodad]

Looks like Eric Rogell will be doing a 2nd test of the C-Max Hybrid to specialize around fuel economy.

 

 

Getting to the bottom of Ford's hybrid fuel economy controversy

http://www.treehugger.com/cars/getting-bottom-fords-hybrid-fuel-economy-controversy.html

 

 

[SnowStorm]

Ecodad, I'm glad you pointed this out.  This Ford 47 mph topic has become quite an interesting issue.   Here are my thoughts.

 

A second test is all well and good but I doubt it will do much to clear up the "controversy".  Why?  He plans to "drive it as I think any normal, reasonable person would drive".  That makes sense as a comparison to "normal" people and driving but the EPA tests (especially highway) are anything but normal.  There are two main highway tests and they both average 48 mph!  Very few people will consider 48 mph "normal" on a highway (OK, I can think of a few!).  The so called "high speed" test even has 7 stops (or near stops) during the 8 mile run.  With the start/stop at the beginning/end that's one every mile!  Really!  Who considers highway driving "normal" when you stop at each mile post!  Today you go to 65 or 70 mph, set the cruise, roll on for two hours and hit the rest stop.  That's 130+ miles non-stop.

But, the points will be raised that:

   1) "we all know that",

   2) "the EPA data is adjusted down to compensate",

   3) "the tests are for comparison purposes" (one car to another - not to real world - "your mileage may vary"), and

   4) "other cars get real world mileage that compares well with EPA values".

The problem is, those points only hold until you start building a really good hybrid.  That is, one capable of doing a lot of driving in electric only (EV) mode.  The C-Max can go to 62 mph in EV mode which should allow it to go through a significant portion of the EPA tests without the gasoline engine running.  Which is exactly as it should be.  Its not just "designing to the test".  The "better" the hybrid, the more the EPA test will disagree with "real world"!  Gasoline engines are terribly inefficient at light load.  You only want to run them upwards of half throttle and several thousand rpm.  That's a lot more power than you need to go 48 mph.  So, the stronger the electric motor/battery combination are, the less you need to run the gasoline engine.  And when it does run, it will be a lot more efficient.

 

Summary points, IMHO, are:

   1) The C-Max's EPA highway millage may exceed your "real world" values because its a better design!

   2) Standard cars and "mild" hybrids have a better EPA to real world match because the system has been adjusted to those technologies.

   3) Ford didn't inflate the numbers or test incorrectly.  We'll find out for sure if the EPA re-runs the tests.

   4) We need to stop making comparisons to those companies that messed up on their tests.  The situation here is different.

   5) Ford's desire to work with the EPA to create a better rating system is precisely what needs to be done.  They should be commended for this position.

   6) The EPA tests were probably designed for emissions tests originally and just adapted for fuel economy (rather than run additional tests).

   7) Other cars may do a bit better real world due to less weight and, possibly, less wind resistance (a longer car can generally be more aerodynamic).

   8) The industry needs to get over this 47 thing and get on with making better rating systems, batteries and aerodynamics.

 

Now my C-Max just needs to get here so I can put some numbers where my mouth is.

[Max Power]

The need to do things of higher value, like test different fuel mixtures for their affect on MPG.  I grew up in a corn state, but now I avoid ethanol like the plague, as I think my mileage is worse with some of those blends.

 

Several OTR drivers have complained that the lower-sulfur diesel gets worse mileage.  This could be an unfortunate truth or they could be full of BS.  These are the problems that the EPA should work on.

 

I see no reason why we couldn't report real-world mileage on cars as it is collected.  The EPA estimate would be replaced after 12 months(need to account for time of year car is released).

[andrewthall]

Before reading my complaints, let me say that, over all, I love my C-MAX now that I've driven it for 4300 miles. 

 

In all honesty, I would have NEVER bought it if the advertised EPA mileage wasn't 47 mpg.  In city, I get around 42 mpg most of the time.  On the highway, I have NEVER exceeded 38 mpg.  Deep down in my heart, I feel that FORD lied to me.  They had to know what "real-world" driving would get.  Advertising the EPA mpg, while legal, was, at best, deceptive from my point of view.  As much as I like the car, that hurt will not go away.

 

By the way, I am the owner of the Yahoo C-MAX group.  I hope you visit that group and make yourselves welcome.

 

Andrew Thall

Laredo, TX

[zhackwyatt]

I know that this is not the first time a car has gotten less than the EPA numbers.  Has there ever been a case on the planet where a car maker advertised less than the EPA ratings?  

[dtorres]

In the 21 years I've been driving I've never had a car or truck that consistently met its EPA estimates. I expected to get about 40 mpg and that's where I am now.

[Max Power]

Before reading my complaints, let me say that, over all, I love my C-MAX now that I've driven it for 4300 miles. 

 

In all honesty, I would have NEVER bought it if the advertised EPA mileage wasn't 47 mpg.  In city, I get around 42 mpg most of the time.  On the highway, I have NEVER exceeded 38 mpg.  Deep down in my heart, I feel that FORD lied to me.  They had to know what "real-world" driving would get.  Advertising the EPA mpg, while legal, was, at best, deceptive from my point of view.  As much as I like the car, that hurt will not go away.

 

By the way, I am the owner of the Yahoo C-MAX group.  I hope you visit that group and make yourselves welcome.

 

Andrew Thall

Laredo, TX

.

Are you using the Eco-cruise on the highway?  I get 42-43 MPG without any effort on my part at 65 MPH.

http://fordcmaxhybridforum.com/index.php?/topic/1434-i-have-found-the-illusive-mpg-sweet-spot/

 

If you are only getting 38 highway, there is something amiss here.  I get better than that at 70-75 MPH but you have to use the ECO-cruise.

 

I am happy with the mileage.  If Ford had lied about the horsepower that would be a different story.

Edited April 7, 2013 by Max Power