Ethanol Demand Driving Expansion of US Corn Crop; USDA Projects 31% of US Corn for Ethanol in 2016
50 Buses in Pamplona to Run on B100 Biodiesel

Views on 2010 and Beyond for Heavy-Duty Vehicles: Efficiency, Climate Change, and Customers

At the Clean Heavy Duty Vehicle 2007 conference organized by WestStart-CALSTART, the US Army National Automotive Center, and the Federal Transit Administration, a panel of seven engineering managers from top OEMs and powertrain suppliers provided a quick overview of likely technology scenarios for 2010 and what might lay beyond.

The 2010 EPA emissions standard for heavy-duty vehicles is the culmination of years of stair-stepped emissions regulations that have driven the development cycle for all heavy duty manufacturers for more than a decade. Two of the key metrics in that standard are the 0.2 g/bhp-hr NOx and 0.01g/bhp-hr PM limits.

A lead-in to 2010 begins this year, with targets of 1.2 g/bhp-hr NOx and the same PM target.

Given an average 3-year timeline to take a new product into production, all the manufacturers have made their basic technology decisions—albeit not yet announced—on 2010 technology, although some room for tuning remains. All the panelists were in agreement that, once the 2010 products are in development, they can turn more of their focus to what comes next.

This is the first time in many years, as Dr. Wayne Eckerle, Executive Director of Research and Technology at Cummins said, that the manufacturers “don’t have an impending legislative limit that we need to meet that I’m not sure how to meet.

For the manufacturers, that expanded focus includes on-going improvements in reliability and operational efficiency of the 2010 products currently under development. An example would be meeting emissions requirements in increasingly efficient ways—for example, meeting NOx limits via advanced combustion and without aftertreatment systems.

On that topic specifically, Alan Karkkainen, Director, Future Technologies, Engine Engineering for International Truck & Engine, noted “Will we get to 2010 by 2010 [with only advanced combustion]? Probably not. By 2012 or 2014, probably.

Related to that focus on increasing efficiency of emissions management will be a much greater focus on fuel efficiency, especially related to reducing greenhouse gas emissions. Meeting anticipated, but as yet undefined, climate change regulations is on everyone’s radar screens.

When people like these [the scientists of the IPCC] say [climate change] is a real issue, policy will follow shortly thereafter. The next decade will see unprecedented pressure to reduce CO2.

—Dr. Michael Readey, Applied Technology Development Manager, Caterpillar

In addition to those two key areas, the manufacturers will begin to focus more on safety systems, as well as driver comfort and convenience.

Tony Greszler, VP Engineering at Volvo Powertrain and the moderator of the panel, laid out a basic technology menu for 2010 that included:

  • Diesel particulate filters.

  • NOx aftertreatment systems.

  • Advanced combustion, including a range of advanced system components (such as two-stage boosting, injection systems, and variable valve management among others).

  • Control systems and on-board diagnostics (OBD). Dr. Readey from Caterpillar said that in his opinion, OBD poses more of a risk issue than emissions.

  • Hybrids.

  • Waste heat recovery, including the possibility of thermo-electric recovery.

  • Fuels (biofuels and eventually synthetics).

The Diesel particulate Filter is already becoming common on heavy-duty platforms to meet the 2007 limits. As the manufacturers head into 2010, they all see a need for some form of NOx aftertreatment. Greszler said “I’m not aware of anybody that will attempt to meet 2010 NOx without some kind of aftertreatment.

Although urea-based SCR is the odds-on favorite at this point, with its greater than 80% conversion efficiencies, it is not the only choice nor is it without concerns, related to infrastructure, operational convenience, and vehicle layout.

While the extra tank and injector required for a urea-based system is likely not a problem on a long-haul Class 8 truck, Karkkainen noted, “The truck is only part of the tool in a medium-duty application. With a mobile crane, for example, there is no room under the body [for the urea system].

There is also some worry that, given potential technology developments, urea SCR could become a stranded technology several years after its implementation.

Another option for NOx control is a lean NOx adsorber (trap). Such LNTs offer excellent NOx reduction when new, but have some issues with cost, durability and engine management during desulfation. Some see it as likely on lighter duty applications, but questionable on the heaviest duty vehicles.

Cummins earlier this year paired its new 6.7-liter turbodiesel with an advanced aftertreatment system including a close-coupled diesel oxidation catalyst, a NOx adsorber catalyst and a combined diesel oxidation/particulate filter to deliver the first 2010-compliant diesel powertrain on the market.

An option that some are exploring is a hybrid aftertreatment system—a combination of lean NOx traps with Selective Catalytic Reduction—to meet NOx limits without having to go to urea.

Eaton Aftertreatment System. Click to enlarge.

Tom Stover, Engineering Manager, Technology, from Eaton, discussed the Eaton Aftertreatment System (EAS), announced last year. (Earlier post.) The EAS combines a fuel reformer catalyst with doser, LNT and SCR technology to create an exhaust aftertreatment system capable of meeting 2010 EPA diesel emissions requirements without the need for a urea storage and injection system.

The hydrocarbon doser feeds the reformer, producing hydrogen and CO—ideal for use in regenerating the LNT. The LNT produces ammonia in significant amounts, according to Stover. In fact, Eaton optimized the system to produce more ammonia than usual. That ammonia becomes the reductant for the second stage SCR catalyst.

Eaton acquired the reformer technology with its acquisition of Catalytica in 2006. (Earlier post.)

Hino is also exploring non-urea approaches with NOx reduction for 2010, according to Masatoshi Shimoda. Hino is using combustion work (high cooled Exhaust Gas Recirculation ration of 29%, high boost and 200 MPa (2,000 bar) injection) to reduce engine-out NOx to 0.75 g/bhp-hr (when hot), then is looking to a variety of aftertreatment systems for the additional required 82% reduction.

Hino is testing a number of non-urea systems, including a single system adsorber, a 2-leg adsorber system, a fuel reformer system, a plasma reformer system as well as a urea system. In early testing, the company had its best results with the urea system and the plasma reformer, although Shimoda said that the 2-leg system has room for improvement. The company begins feasibility studies in March 2007.

On the combustion front, there is a wide variety of work underway in exploring the use of increased injection pressure, higher boosting and higher cooled EGR ratios in addition to work with HCCI and Partial HCCI combustion regimes.

In a separate presentation at the conference, Per Andersson, a Technical Specialist from Ricardo, characterized HCCI combustion as “like balancing on a knife’s edge—the combustion can’t be too rich nor too lean, and at a temperature not too high to form NOx, but not too low to misfire.”

These engines are sensitive to virtually everything... a change in environment, fuel, the engine has to take care of it.

—Per Andersson

Challenges at low load and high load are quite different for HCCI combustion, especially on a heavy duty vehicle. Among the technologies being explored are different injection systems (such as dual-mode injectors) and strategies, variable valve management on a per-cylinder basis, variable compression ratio engines, further development of EGR and boosting systems,and mixed-mode strategies.

Making all that work requires significant development of sensors and control systems. The focus on engine work will result in a need for increased base engine strength to handle higher cylinder pressure and injection loading, and especially more sophisticated controls and On-Board Diagnostics.

Hybridization is seen almost as a given beyond 2010 in the current environment. Volvo, Hino and International all have heavy-duty hybrid vehicles and Eaton is about to begin production of its medium-duty hybrid drivetrain (earlier post) and is further developing its heavy-duty hybrid drivetrain. Cummins is working on hybrids, and Caterpillar is working on both on-road and off-road hybrids.

Eckerle from Cummins noted that “as we start heading to hybrids, we want to make sure we optimize the power density in the engines.

One regulatory issue outstanding in this area is that there as yet no provision to certify a hybrid cycle. Manufacturers thus need to certify the hybrid vehicle on the base engine, noted Greszler, thereby limiting the opportunity for optimizing the hybrid cycle.

Waste heat recovery is seeing a big emphasis as a means to pushing up the overall brake thermal efficiency of the systems to 50% or better from the current low 40s, and Cummins is actively developing Rankin cycle conversion of EGR heat to electric power.

Eckerle said that Cummins has recovered about 57 hp from its Rankine cycle waste heat recovery system. The question, he said, is making it cost-effective. He sketched out a series of steps that could push BTE over 50%. Starting at a current base of 42% BTE, Cummins thinks it can deliver:

  • 5 percentage points in improvement with combustion and air handling;

  • 1.5 percentage points with EGR Loop

  • 1.5 percentage points with optimized controls and calibration

  • 1.5 percentage points with improving PM aftertreatment—reducing the time required for thermal management on the engine, as well as active regeneration;

  • 5 percentage points with waste heat recovery and electric accessories.

The biofuel currently at the forefront of the heavy-duty industry is biodiesel. All the manufacturers are taking that also as a given, but note that more work needs to be done on quality—including on the blending side—as well as on understanding the emissions impact.

We’re working with EPA to understand what is the impact of biodiesel on emissions. It’s too early to say what is happening with post 07 technology. It’s not just the engines, its also the aftertreatment systems with their injection systems...but this [biodiesel use] is happening, and we will need to modify whatever aftertreatment systems we need to to work with the fuels, provided the fuel is quality.

—Dr. Readey

Cummins, which will shortly announced B20 compatibility for its 2007 engines, is actively working with the refineries to get away from splash blending, which can have variable results.

We'd like to get away from splash blending. We need a national approach, so we all have the same fuels.

—Dr. Eckerle

The major alternative fuel for heavy duty vehicles currently is natural gas, and Graham Williams, Director Global Heavy Duty Programs for Westport Innovations, a major provider of gas engine technology, noted that in terms of 2010 technology, his company “will likely follow what the diesel industry gives us and for good reasons.

The diesel industry will make it, natural gas will follow, but we will retain where possible the characteristics of well-developed diesel products.

—Graham Williams

Westport takes two combustion approaches with natural gas: otto cycle (spark ignited) and diesel cycle (with diesel pilot).

Westport’s joint venture with Cummins (Cummins Westport) will introduce a spark-ignited, 2010-compliant gas engine in June. This is evolutionary technology, and reflects the overall improvement in natural gas engines over the past few years in terms of efficiency.

The engine goes to stoichiometric rather than lean burn and, with addition of EGR, can handle emissions with a simple three-way catalyst. (Earlier post.) The direct-injected, pilot-ignited system (High Pressure Direct Injection—HPDI) changes as little as possible with the diesel engine.

Although natural gas engines are inherently about 50% cleaner than diesel with respect to NOx, there originally was a sizeable efficiency gap due to immaturity and lack of optimization.

Over the last few years, we have dramatically improved the efficiency and retained the emissions reduction compared to diesel, so in 2007 we have a gas engine as efficient as a diesel.

However, meeting the 2010 target with a gas engine on a diesel cycle will be difficult, Williams noted, and for that reason it is likely they’ll follow “what the diesel industry gives us.” Combining HCCI with HPDI is a promising approach.

In terms of greenhouse gas reduction, Williams noted that landfill gas and biogas are both very compatible with Westport’s technology.



Waaa,.. all warm and fuzzy on the inside.
Its alwasy awesome when scientists and engineers do the talking as opposed to CEOs. You just know they want to make the stuff they claim just to prove that it can be done if nothing else, and thats a good attitude.

I always find it very awe inspiring when a particular industry goes at something in full measure. And considering how much heavy machinery these companies manufacture it means a hell of a lot less pollution will be coming from their stuff in the near future.

On a related note, isn't it amazing how lately companies large and small (with their own profit targets and shareholders) decide to make the right environmental decision about their products and services.
Sure there are exceptions, but on the whole the way its now considered 'the new cool' for a company to be environmentally conscious is the most awesome thing I could have hopes for.
All those cumulative Birthday/New year/Christmas wishes asking the same bloody thing (like a billion other people) are starting to slowly come true. :)

Rafael Seidl

NooGums -

I hate to burst your bubble here, but both the switch to ULSD and the introduction of NOx aftertreatment systems are the direct result of tougher emissions regulation by EPA and CARB (same in Europe). Nobody - especially in the commercial space - would voluntarily pay more on both the initial purchase and operations overheads out of concern for the environment. It's not that they don't care, it's just that they need to compete in a cutthroat business environment. Nice guys finish last.

It's really the old free rider problem of game theory fame. Changing the rules is really the only proven way to work around it, because it ensures the field remains level for all the players.



Well said. This is why capitalism needs government regulation in order to succeed long term--otherwise the rational, short-term decisions of the profit-oriented market players will eventually drive the whole system off a cliff.


No this just shows what happens when bussinessmen instead of buricrats and engineeers instead of academiacs handle the job.

If smart people had designed cafe it would have been a rorar suscess AND the companies wouldnt have had trouible implimenting its goals.

Rgars why the new cafe basicaly tries to chop up the fleet into segments that they hope align on the tasts the car/truck beeds to perform.


No this just shows what happens when bussinessmen instead of buricrats and engineeers instead of academiacs handle the job.

Oh, BS. Stop spouting dittohead garbage.

If smart people had designed cafe it would have been a rorar suscess AND the companies wouldnt have had trouible implimenting its goals.

CAFE was designed by Detroit's lobbyists. If smart people had designed it, Detroit would not be at death's door today, and suburban moms wouldn't be driving around in Monster Trucks.


In CAFE standards you have a confluence of special interests from both Left and Right. Labor unions in the form of the UAW, and corporate interests. One of the strongest opponents to raising the standards is Michigan's John Dingell, a Democrat.

IMO, stupidly implemented regulations are worse than none at all.

John Baldwin

run the vehicles on 100% natural gas (CNG or LNG).
No problems meeting emissions, include a % of bio-methane and the CO2 comes further down.

Rafael Seidl

John -

CNG and LNG are useful alternatives, especially in places with a serious air quality problem and access to sufficient quantities of the fuel. The latter is a problem in China and much of the US, less so in much of the the EU and certain countries elsewhere (e.g. Argentina, Pakistan). Japan has been importing LNG for many years and now has pipelines down from Sakhalin Island. India is looking to pipe gas from Iran.

Improvements in gas engine technology, especially direct injection (expected soon), ignition chambers with glow plugs (MAN) and integration of CNG tanks into the load-bearing structure will make this alternative more attractive. Mobile LNG tanks pose special operating and crash safety problems and are only being considered for specialty vehicles.

The main problem for gas-fired engines is that diesel is still quite a bit cheaper on a TCO basis. Therefore, it's not going away anytime soon and solutions for cleaning up the emissions are needed.

Murad Ismailov

Among various approached to get Diesel engines Clean there is still a window to work on Diesel injection and combustion control. Let’s assume that you have a quai-homogeneous charge of the fuel spray instead of conventional highly stratified Diesel spray. That allows you to shorten ignition delay, control combustion temperature (NOx) phasing properly the injection start and its duration within the engine map and get our of diffusion combustion (soot).

I am working on these problems straightly from inside of the combustion chamber in order to decrease, at least, the requirements on particular matter and NOx aftertreatment. Our final goal is to make a Clean Diesel operation without a need for quite expensive aftertreastment.


I was alive and well back then I KNOW exactly what went on bub.

You had comnpanies whose main product was trucks all of a sudden having fleet averages cppared to other cmpanies whose main product was small cars. It was like having catapiller and porche dealing with the same regs as yugo.

What the car companies wanted was what they are FINALY getting after all these stupid years. Cafe based not on fleet average but roughly on what the hell the thing is made to do.

Compacts with compacts trucks with trucks and so on.

As the car companies themselves said AT THE TIME fleet average would result in a lower and slower increase in overall milage as not all cpmanies would EVER be able to make a small car brand in america,

Or do I have to pound it into your mtv addled brain why not everyone ever was going to buy a small car from ford vs toyota even when it was the same damn car....?

When I shop for a smallish car I sure ad bloody hell dont shop ford or gm I shop toyota or honda or hunudai. When I want a large sedan I sure as bleep dont go looking for kia. This is REAL bleeping life and cafe as it was wasnt a part of it.

Stan Peterson

Anti-capitalist idiots think poliiticaian give a ruddy damn about anything other than themselves. The biggest botches of the envioronment were the East bloc Communist paradisess where no one had to worry about profit or making a product that anyone would want.

right now the Democrats have only owo favorite industries. Big Law and Big Media.

Everyone else according to them are corrupt somehow.

Isn't it interesting that the the Law which teaches the ambulance chasers the right way to lie and steal for profit; and the big media Hollywood types in which actors practice to convicingly lie and create a false impressions are just the fields that the demagogic Democrats love?


Could it be becasue they are liars and respect other accomplished liars too? Just professional courtesy...


As Hollywood Actor Ronald Reagan used to say, "There you go again, Stan." Rafael Seidl and Nick gave a cogent explanation for why capitalism needs some regulation to obtain the best outcome for the country. You and Wintermane suddenly talk about "anti capitalists" and "communists" as though you hadn't even read what was written. This is a success story, where regulation worked. It has gotten the pollutants down. It induced industry to innovate and come up with better solutions. The same story played out in the 60's through the 90's with passenger protection, crashworthyness, and emissions, among other things. Left to the free market, do you think we would have the clean safe vehicles we have today? I don't.

Wintermane is trying to argue for special classes of CAFE regs for the loser companies that can't make efficient vehicles. The point is not to maximize GM's profit at the expense of the trade deficit (which get swollen by oil imports), the point is to optimize the US economy and environment for the benefit of all, even if it means dragging GM kicking and screaming to a business model consistent with that goal. If GM were a small company selling Faberge Eggs, then fine, let the free market reign. But the provision of the single most important component of our countries transportation infrastructure is too important to leave to the unbridled free market. Read what Rafael wrote about the free rider problem.


I could expect all the stuff behind a segmented cafe but I dont have to its already a done deal its already comming.

The results are all that matter and it SHOULD get better results then the old cafe ever did.

IF all goes as planned it shoiuld result in better cars and less fuss.


Mind you if everything goes as planned s about the same as saying is flaming hippos fly out of my ass singing baravrian opera...

One reaosn cpmapnies always try to go slow on these things is nothing ever goes right and buracratic systems often cause total cluser muffs for companies when things dont go as planned.

99% of what the companies expend mobey on is dealing woth what they arnt expecting.

Gil Pearson

There is absolutely no mention of DME in this article. Is this absolutely a "dead horse"? If so, why?


Dme is likely not mentioned simply because we dont seem to be going that way. Its a very good fuel thats for sure but for some odd reason no oe in the us seems to be on it.


IMO, stupidly implemented regulations are worse than none at all
So the improvement in average US efficient of 18mpg in 1978 to 27mpg in 1990 has nothing to do with CAFE?
Likewise the fact that efficient is stuck at 27mpg has nothing to do with fact that the GOP has frozen CAFE.


Actauly the effiency of us cars has gone up since then the energy value of the fuel went down on average as they added various things to the fuel. Also the new improved cafe does in fact raise overal milage goals and likely will be modded soon to raise them even further.

And I would point out bush was the ONLY one who managed to raise a cafe milage value at all and that was for light trucks by 5%. Congress itself is too gutless to take the hits that would come from a shaep cafe boost BOTH sides are.

Oh and ill point out to everyone o the planet that bush did more for alternative fuel and people buying higher milage cars simply by going to war with iraq then any other president on earth ever... Might not have ment to tho;/

John Reed

Diesel to CNG conversions that meet the 2010 standard ARE HERE
Too bad the EPA and the AQMD are so in love with Cummins/Westport that they won't allow any other companies to share in the funding they are passing around to try and do what Omnitek has already accomplished. The EPA can't seem to figure out how to classify an older diesel engine that has been converted from diesel to CNG, so instead of applying the required emmissions reductions standards for older diesels, they require these conversions to be re-certified as NEW CNG motors, having to meet the strictest standards currently written for IC motors. This forces fleet owners to have only ONE option..add on systems to reduce emmissions that decrease engine life, fuel economy and profits! Switching to CNG would dramatically reduce emissions, increase engine life, and save the fleet owners money. Just whose ass is the EPA covering here?

The comments to this entry are closed.