Tenneco: Talking about Emissions

Gary S. Vasilash

Meeting 54.5 mpg by 2025 is challenging enough. But as Tim Jackson and his colleagues at Tenneco know there are some emissions standards that are going to kick in starting model year 2017 that may be even more daunting.

While it seems that everyone is aware of the impending 2025 CAFE regulations that will have a fleet average of 54.5 mpg,  which is seemingly remarkable and which will have a nontrivial effect on engine design, engineering and even production and which will also lead to a greater prevalence of non-combustion and combustion-assist alternatives (e.g.,  electric vehicles and extended-range electric vehicles, wherein the combustion engine is used to change the battery pack, not turn the wheels), there is another regulation that will begin to take effect in 2017 with its culmination in 2025 that is probably even more demanding.

That is, the CAFE regulation has  a footprint-based scale for the  required miles per gallon. Essen- tially, the smaller the car, the higher the required fuel efficiency. So as it is written in the Federal Register (vol. 77, no. 199), a compact car (and the Honda Fit is used as an example) would need to be at 61.l mpg, a midsize (Ford Fusion) at 54.9 mpg, and a full-size car (Chrysler 300) at 48.0 mpg.

But as Tim Jackson, executive vice president, Technology, Strategy and Business Development, Tenneco (tenneco.com), points out, the U.S. EPA Tier 3 regulations, which begin in model year 2017 for passenger cars and model year 2018 for light trucks (and it also impacts Class 2 and 3 diesel pickups), is a “milligram per mile” standard: “The biggest pickup is held to the same standard as the smallest B-segment vehicle in terms of absolute emissions at the tail pipe,” he says.

Previously, pickups had been measured on milligrams per horsepower, so bigger engines had a bigger emissions window.

Tier 3, Jackson explains, is about the reduction of “criteria pollutants,” the precursors to ozone, such as NOx and non-methane organic gas (NMOG), as it the aldehydes, ketone, and alcohols in the exhaust stream.

Remember Tier 2, Bin 8? Well, if you’re familiar with it, then remember is what you’re going to do when Tier 3 is in full effect. Right now, Tier 2, Bin 8 is 125 mg/mile of NMOG and 200 mg/ mile of NOx, or a total of 325 mg/ mile. That is going away. As are Bin 7 and Bin 6. So the highest level at which an engine can be certified is what was once Bin 5, but it is being split into Bin 160 and Bin 125.

Tier 3, Bin 160 is 90 mg/mile of NMOG and 70 mg/mile of NOx, or a 51% decrease from Tier 2, Bin 8. That’s the highest level.

But Jackson points out that the fleet average that is being required is what has been known as Tier 2, Bin 2. That’s 10 mg/mile of NMOG and 20 mg/mile of NOx, for a total of 30 (which explains the new nomenclature, Tier 3,  Bin 30).

According to Jackson, to get a fleet average to Tier 3, Bin 30—a 92% reduction from Tier 2, Bin 8,  incidentally—if there is one vehicle  at Tier 3, Bin 160, it will be necessary to sell around 13 vehicles that are at Tier 3, Bin 20 to offset that higher emissions number.

So what this means, in effect, that by 2025, cars and light-duty trucks will both have a fleet average by 2025 of what is today’s Tier 2, Bin 2.

Oh, and it gets even more inter- esting. Jackson explains that the first 90 seconds of the federal test cycle are the most crucial: “If you don’t get the after-treatment up and running and to the temperature where it is removing the criteria pollutants, it is all going to be over in the first 75 to 90 seconds of the Federal test protocol, because you will already have blown through the limit. Even if you ran at zero emissions for the rest of the 30-minute test cycle, it’s over.” He says, “Bag Zero and Bag One are absolutely critical under the Tier 3 legislation.”

One more thing: while the current regulation calls for an emissions warranty of 120,000 miles, that goes up to 150,000 miles. In model year 2017.

Recognize that these tail-pipe emissions requirements are independent of the fuel efficiency requirements.

Jackson points out, “Tier 3 vehicles are going to be so clean that if you drive them in an area like Chicago, Detroit or Los Angeles, the air coming out of the tail pipe is going to be cleaner than the air going into the vehicle’s air cleaner.” Electric vehicles, he points out, are not  as environmentally beneficial:  “If you are driving an electric vehicle, you’re not helping to clean the air like you are with an internal combustion engine.” A Tier 3 internal combustion engine, that is.

“After treatment and thermal management is where we are going to add value to the vehicle manufacturers,” says Ben Patel, Tenneco vp, Emissions Control, Global Research & Development and Systems Integration.

Tenneco, which had $8-billion in  2013 revenue, of which 68% (or  $5.5-billion) was accounted for by  its Clean Air Div., is, not surprisingly,  focused on developing technologies that can help vehicle manu- facturers address these and other  regulations. Among the developments that they have created is a fabricated exhaust manifold rather than cast, in order to both reduce weight while maintaining temperature (helpful for getting the catalyst up to temperature faster); they’re also moving the catalyst closer to the engine.

They are also working with Gentherm (gentherm.com) on a waste-heat recovery system that is used to generate electricity via a thermoelectric generator: essentially, it is a heat exchanger that has thermoelectric material sandwiched within cylindrically shaped cartridges. When the cartridges are exposed to hot exhaust gas on one side and engine coolant on the other, then the consequent temperature gradient results in an electrical current flow. This electricity can then be used to power on-board systems.

It almost seems as if there are few things that they aren’t working on for light-vehicle powertrains, be they conventional gasoline engines (catalytic converter systems; close-coupled converters; ultra-thin substrate converters; semi-active muffler valve technology; fabricated manifolds; lightweight mufflers and thin-wall pipes; active and passive valves; thermo-electric generator), gasoline direct-injected engines (add gasoline particulate filters, heat exchangers, NOx abatement to the foregoing), diesel engines (gaseous ammonia injection; diesel particulate filters; diesel oxidation catalysts; SCR; NOX adsorber; fabricated manifolds; lightweight mufflers and thin- wall pipes; heat exchangers; vaporizers; electronic EGR valves; low-temperature SCR; SCR coated filters; compact mixing), and even gasoline and diesel hybrids, be they micro, mild, full, or plug-in (catalytic converter systems; ultra-thin substrate converters; diesel aftertreatment; semi-active muffler valve technology; fabricated manifolds; lightweight mufflers and thin-wall pipes; heat exchangers).

Whereas some companies find meeting emissions requirements— and Jackson points out that regulations are global, with variations from country to country, but overall a tightening of the requirements—to be a challenge, at Tenneco, it is an opportunity, and a big one at that. They estimate that the original equipment market for Clean Air will be $100-billion by 2025, including light vehicles, commercial truck, off-highway, locomotives and marine, and stationary applications; of that number, light vehicles account for 50% (although Tenneco has technologies that address each of those categories).

“Last year,” Jackson says, “we spent about $313-million on engineering research and development out of $8-billion in revenue. We want to make sure we have the right technologies for our customers so that they can achieve emissions compliance and great vehicle dynamics.” (Walker and Monroe, which are ride-and-handling component and system suppliers, are the Ride Performance part of Tenneco’s business, which represents some 32% of the revenue, with Clean Air accounting for the rest.)

As the industry moves toward 2018 and beyond, clearly that’s money well spent.