Electrically Assisted Diesel Particulate Filter Could Save Fuel in Heavy-Duty Pickups

Electrically-Assisted Diesel Particulate Filter Could Save Fuel in Heavy-Duty Pickups

GM and Oak Ridge National Laboratory are jointly developing new emissions-cleaning technology that promises better fuel economy for future heavy-duty diesel truck buyers, according to a presentation given during the U.S. Department of Energy's 2011 Merit Review in Washington, D.C.

In 2007, the EPA cracked down on the amount of soot diesel engines could produce, cutting allowable emissions by 90 percent from 2006 levels. In response, truck makers and their powertrain partners created diesel particulate filters to trap soot, a byproduct of diesel’s lean combustion process because not all the fuel is burned.

While cleaning soot from diesel exhaust is great for the environment, it comes with a price. After a while, depending on workload and driving distance, the DPF becomes full and needs to be cleaned out, like a self-cleaning oven. In today's HD pickups, extra diesel fuel is injected into the exhaust stream to boost temperatures in the DPF to more than 1,000 degrees, incinerating the trapped soot. That process can require up to six-tenths of a gallon of diesel – an amount large enough to dent fuel economy and drivers' wallets. It can also take five to 10 minutes, depending on trapped soot levels.

Fuel economy has long been the advantage of diesel over gas engines, returning up to 20 percent to 30 percent better mileage, but DPFs have eaten away at this advantage.

EPA Emissions Levels for Diesels

GM and ORNL have created a solution to the mileage problem that could reduce the fuel economy penalty of DPF regeneration by at least 25 percent by 2015 relative a 2008 baseline, according to the presentation.

Instead of using diesel fuel, an electric heater placed at the front of the DPF is used to raise temperatures to the point where the trapped soot is incinerated, at around 1,112-degrees.

So far, an experimental electric heater has been tested on a small-displacement 1.9-liter four-cylinder GM diesel engine, but a project member from ORNL says the solution is scalable to heavy-duty pickups with large-displacement oil burners, like GM's 6.6-liter Duramax V-8.

With the 1.9-liter engine, the electrically assisted DPF has been shown to remove up to 95 percent of soot and cuts regeneration times by 75 percent.

Improved fuel economy using an EA-DPF should also please the EPA, which is getting tough on diesel engines again. Heavy-duty pickups, currently excluded from federal fuel economy standards, will have to meet the first mileage regulations by 2016.

The electrically assisted diesel particulate filter project is being financed with $1.3 million split evenly between GM and ORNL. It runs through September 2012.




[Source: U.S. Department of Energy]


Damn this was my idea...

I also thought about using some type of laser to hit and burn the soot particles in flight.

can someone explain to me how they have gone green (since '08)by adding all this emission BS and yet we burn twice if not three times more fuel, how is that getting greener

This was done on a 1.9L diesel engine...not a 6.6L. VW has had a TDI with DPFs getting 40+mpg no problem. It is an issue with the bigger motors because they obviously create more soot. Another example of our tax dollars wasted by a bunch of tree hugging hippies. The moment I got my 08 6.4 I cut that piece of crap DPF off...what a waste of fuel and for what? To stop a little black soot from exiting the tail pipe? Unless I get on it that truck barely smokes and that is with a tune. I am so fed up with the EPA and the Liberals who freaking support them. I hope Ron Paul goes all the way and gets elected and one of the agencies that gets cut is the EPA!!

were can I retro-fit my GMC topkick? I love to get 20-30% MPG back!


I pull a horse trailer and when I'm not doing that I pull a 5th wheel, I'll gladly be a part of this beta testing program

Sounds promising!

@ dan the man

Really?! 3 times the fuel? I take it you were then getting about 50-60 MPG in your old 5.9 Cummins or 7.3 Powerstroke compared to the abysmal 17-20 they are getting today?

How dare they! Not to mention that pesky HP increase of 250% and torque increase of 200% Blasphemy!

(where is my eye-rolling smiley face when I need it)

the only justified arguement you can make is the increase in the price of the motor and only part of it can be attributed to the emissions regs, the rest is in the power increases.

lead the way gm!! im tired of the ford did it first crap

Couldn't agree more with Justin. Thanks for your comment.

@ Justin

Did you bother to read the last few sentences. In case you didn't here it is:

"The electrically assisted diesel particulate filter project is being financed with $1.3 million split evenly between GM and ORNL"

This was financed by the two companines partnering up. They got financing from someone like me at a bank not from the DOE or EPA.

If you are going to hate on a useful new technology that can provide jobs to Americans and be exported around the world at a profit at least hate in the right direction.

@chevy guy - GM has done a few things before Ford. Balout comes to mind;)

this would be better than that stupid def fluid. i hope this goes somewhere.

@Chevy Guy, we will still say "Ford led the way first!" :)

@hemi LOL
This does not replace the DEF. DEF is for filtering out NOx which contributes to ACID rain production. However, I've read of research where they use a cartridge based medium to take the place of liquid urea (can't remember who), or they use a special catalyst which is what Honda is researching. Those are the approaches I'm watching, as it'd be nice to just change a cartridge every oil change or so; in the case of Honda, the medium would be good for at least 100,000 miles. I believe the current Cummins 6.7 in the ram does something similar, but the Honda version had something special about it I can't remember that caught my eye.

Eventually creativity overwhelms brute force. Current DPF filter design reminds me of the old smog pump days.

Good for GM, however, I believe this tech will be dead before it even hits the road. Kind of a waist of R&D.

Cummins is working on an engine that wont need DPFs, or NOX scrubbers. However, it is still 3 to 4 years into the future.

What sticks out in the article, soot is the result of unburnt fuel. Why don't they attack this combustion problem rather than chase the problem in the exhaust?
Work with refiners in the fuel making process, injectors, piston design............the list goes on. Make that engine burn more efficient helping and/or eliminate this exhaust problem.

Where is that electricity coming from ? Engine again, to burn more fuel ?
Thank you very much smart engineers.

As usuall GM is leading the way to a better future. I get 20 mpg with my 2011 Dmax 1 ton, that is all i could ask for with so much power.

i agree with justin. That'd be the first thing I would do if I had a truck with that crap on it.

Makes me wonder, why dont cars use giant particulate filters alonge with 2 to3 catalytic converters+egr? After all, gas engines are less efficient and emite worse exhaust fumes.

Then again, what can you expect from people who can be tricked into banning dihydrogen monoxide lol

The last few days these PUT stories have been painfully slow to load!

Slow for me as well. Thought it was on my end. I'm thrilled to see so much r&d on diesel lately. What took so long.

GM only supplied en engine and $$$ (bailout money)...
Credit goes to Oak Ridge Lab engineers.

Ford is best

The last few days these PUT stories have been painfully slow to load!

@ Ken

Slow for me as well. Thought it was on my end. I'm thrilled to see so much r&d on diesel lately. What took so long.

Yea me to

Sorry for the page load problem. We're working to find the source of the delay.

OK, just to clear up confususion...
Oak Ridge National Laboratory is part of the DOE, and thus tax funded-http://en.wikipedia.org/wiki/Oak_Ridge_National_Laboratory
so the assesment that tax money is being used here, is correct- not very much, however, as gov't research goes.
NOx and Particulates are a product of all diesel engines, from Onan generators to VW TDI's, all the way to ocean supertankers.
@Southern IL Man- In every modern engine development program, reduction of soot and NOx are key factors, before after-treatment ever comes into play.
@comment posted- that would be the holy grail everyone is chasing, but I just don't think it'll happen.
@zviera- nail on the head, but with some clever strategies, they could use a alternator regenerative system, like BMW has. Expect alternators to grow over 3kW output very soon.
To me it would seem like South West Research would have been a more capable partner. Oak Ridge doesnt have nearly the kind of diesel R&D capacity that SWRI has.
@Justin- the fact that VW has DPF vehicles getting 40mpg means nothing without giving comaritive numbers w/o them. Every diesel makes soot.


Todays DPF trucks arent getting 17-20MPG

More like 13 around town and 15 on the highway.

I miss my LBZ duramax, 17.3 consistantly in town and 18-20 on the highway.

Damn DPF, damn hippies...

Todays DPF trucks arent getting 17-20MPG
More like 13 around town and 15 on the highway

when we got our '08 F450's 4:30 gears crewcabs 9' reading body we were getting 9 MPG's took out the DPF's and gave them a tune to stop the regen we are now getting 14 to 16 MPGS

@ Ryan

I'll give you the 13-15 mpg figure, it is probably the most reasonable, but to hear it from most of the commenters on PUTC they ALWAYS get way too good of mileage. Still it is not 1/3rd the mileage as claimed above. That's just beyond ridiculous.

In my defense Mike has gotten 22 mpg highway in a new F-250 and others report 20 for the new Duramax.


Part of the reason you get terrible mileage is you have an 08 Ford. It has been noted as one of their worst engine designs and was quickly replaced. I have no doubts the truck is strong but the motor wasn't good to begin with. Mike Levine himself has gotten 22 mpg in an F250 (I know yours is heavier being a 450) and I'd imagine that the new ones with the new 6.7 are getting very high teens WITH the DPF and regen on.

@ mhowarth

gm gets better gas mileage unloaded then the ford it's in the rumble in the rockies thread

@ mhowarth

as far as the engines go they are solid as a rock we have three off them (6.4's) and combined we have well over 300,000 miles on them and all we have done is replaced one fuel pump and considering these trucks pull 10,000lbs every where they go, as for the FE i have yet to run across a Dodge or GMC that got any better FE in the same years, it really is a shame what Emissions have done to Diesel trucks, now the newer trucks (6.7's) i hear they are getting about 10% better FE and we see a lot of the new Fords in our area and people really like them but we will see what happens

@ Chevy Guy
my friend has a '11 durasmash 2500 Crew cab the best he can muster is 12 MPG's and 9 MPG's pulling and we get 10 pulling and 14 to 16 MPG's with no trailer but like i said we have tunes in our trucks

For any fellow dorks/nerds out there...


@ Chevy guy

I was actually looking for that article but the site is running so slow it took me upwards of 30 minutes just to get the number for the Ford from its standalone test.

@ dan

I am glad they have been trouble free for you other than mileage. They have a pretty bad reputation for reliability with expensive repairs. No one bats 1.000 though.

Some of the retrofit DPF's in use in California are electric. They require being plugged in to 220v. overnight as they are not powred by the vehicle's electrical system.

Sounds good. Keep up the good work

I read this article that the more stuff that you put on your car to "improve" fuel economy will actually burn more fuel than ever. I read that one car caught on fire when this gadget was installed on a car.


Mike I got my 2011 Ram 3500 4x4 Cummins High Output 800 ft-lbs two days ago and it is getting awesome mpg! I figure I'm probably one of the first in the country with one. Mine is a single rear wheel with 4.10 gears.

The 6.4 wasn't cancelled because of bad engine design, it was cancelled because of a rift between Ford and Navistar dating back to the 6.0 debacle.

I own a 2011 Denali HD, and I hate the regen process. Granted the 2011's only regen once every other tank, but it drops my mileage down to about 10 mpg. My overall average is about 16-17 for mixed driving, which isn't bad. I think this technology would make it better, however when they say it is scalable... see how much of a benefit it is. I've looked into putting the DPF in a recycle bin, but the warranty and emissions kinda outweigh the possible gains. I hope Banks comes up with some toys for these soon.

@ typhoon5000
if that is true you are one lucky man that's the best i have ever heard

Poor wording in the article. Implies that fuel penalty for DPF is 20-25%. No, the penalty is about 2-3% or less. This electrical system does cut that in some not all circumstances.
For the skeptics who want to break the law by removing the DPF you are going to damage your engine. It was set up to take into account the back pressure of the whole emissions control systems. Anything you thought you were gaining has just gone right down your tailpipe in worse engine performance.
To those who think it's a tree-hugging exercise, just ask if you really want to breathe in the dark clouds of diesel dust of yesteryear. It's so unusual these days to see the dark clouds that we are offended when we see it because we think of that truck owner as a no-good polluter: AND THEY ARE!

By decreasing the gas consumption, vehicles could travel more, especially ones with trailers attached to them. I'm hoping that they will be able to implement this in the near future.

damn hippies.

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