Motoring onward: part two of emissions regimes

[kscarbel2]

Today's Trucking / March 3, 2015

Apples and oranges. That's how Brian Mormino describes the difference between the emissions regimes of the previous decade and the one that was launched last year and will enter its second phase in 2020. Executive director, worldwide environmental strategy and compliance at Cummins, he says all the hard work and heartache of dealing with engine emissions from 2002 on to 2010 has left us well equipped for the next steps.

We've already taken the first of those steps, starting a year ago, with Phase 1 of the fuel economy and greenhouse gas regulations as decreed by President Obama. Back in 2010, with so-called 'criteria' pollutants like nitrogen oxide (NOx) under control, he ordered the Environmental Protection Agency (EPA) and the National Highway Traffic Administration to move on. He told them to cut carbon dioxide (CO2) emissions, along with other gases in lesser amounts, while improving fuel economy in medium- and heavy-duty trucks.

The challenge was anything but small, the timeline short, but the 2014 targets were met, largely because so much had already been achieved. And the next target in 2017 will be met as well.

"I'd like to help people understand that the industry is in a great place from the standpoint of technology and the future," Mormino told me in a lengthy recent interview. "What I mean by that is that we now have diesel particulate filters, we have SCR systems, we're taking care of emissions in the exhaust. And we have learned and improved on those systems.

"And so when we look at meeting the first GHG and fuel-consumption standard in 2013, a year early, how did Cummins do that? We did it by improving the engine architecture that we already had in place. And what are we going to do for 2017? We're going to improve on the engine architecture that we already have in place. And I would even venture to say that when we look at 2021, we're going to improve on the engine architecture that we already have in place."

The New Regime

Phase 1 of the GHG and fuel-economy regime does not involve just engines as in the past, but trucks as well, with tires and aerodynamic devices tested and taken into account. The present 2014-19 rules say that heavy-duty tractors must achieve as much as a 20-percent reduction in CO2 emissions and fuel consumption by 2017, a little more by 2019. Engines, tested separately, had to improve three percent by 2014, and six percent by 2017. Mixers, refuse haulers, and other vocational machines must get to a 10-percent reduction in fuel consumption by 2017.

None of this change caused a stir last year, and initial targets were met with ordinary improvements of existing hardware and software. Things will get tougher on engines in 2017 but radically new hardware -- like waste-heat recovery -- won't be required.

When these rules were announced it seemed to many observers that, with so many variations in commercial vehicles, it would be near impossible to find a standard that applies to all. But not so, apparently, and for reasons similar to those cited by Mormino.

"It's complicated but we've been able to manage all the configurations in Phase 1," said Sean Waters, director of compliance and regulatory affairs at Daimler Trucks North America. "Mostly we're able to manage all the differences because we spent a lot of money developing fuel-efficient technologies years ago. All those decisions that have paid off for our business and paid off for our customers, have also paid off in the regulatory world and enabled us to deal with all the different configurations out there."

Phase 2 Tougher

Phase 2 of the fuel-efficiency/greenhouse gas regulations will soon be unveiled. A draft rulemaking proposal was due to be released this month by the EPA and NHTSA, but I'm hearing there's a delay. Regardless, the final rule is due some time in 2016, affecting trucks built in 2020 and beyond.

We don't know much about it, and even the people I've talked to lately who keep track of what's going on in Washington can only guess. All we really know is that Phase 2 will demand even tougher, more stringent CO2 and fuel-consumption reductions. Much tougher, it seems. But our firm knowledge stops there.

Will trailers be added to the mix? It's almost certain, it seems, and there are suggestions that it will happen in 2018. At least for dry vans and reefers.

One test or two?

Engines and vehicles are tested separately in Phase 1, but there are those who urge that just one test, with engines rolled into the whole truck like any other component, is the better approach for Phase 2. Both sides are pretty vehement.

As things stand now engines are tested on a dynamometer as they have been all along, and Cummins thinks it should stay that way.

Among other reasons, Mormino says that this would preserve spec'ing flexibility for truck buyers and ensure repeatability in the testing process.

Trucks, on the other hand, are tested by way of computer modelling in Phase 1, with some inputs coming from on-track trials using standard SAE protocols and that data then fed into the modelling software. Daimler and Volvo (including Mack), the only fully integrated OEMs, are arguing that a single all-inclusive test would be simpler and more cost-effective.

Mormino says the implementation of Phase 1 was pretty much seamless, and he attributes that success largely to the continued use of familiar regulatory tools and testing methods that had been in place for decades.

For 30 years engine makers have tested NOx and particulates on the dyno, and it was easy to include CO2 as well.

"We just added CO2," Mormino says, "which means that we allowed all that diversity to continue in the marketplace because the engine is certified to operate in a wide range of vehicles and applications. So customers and end-users still have all the choice that is really, really important... in terms of all of their preferences and the types of work they have to do. The regulation didn't... limit their choices."

Perhaps a more compelling argument is the one he makes about the huge number of fuel-economy variables when a truck is put to use. Like driver skills, terrain, trailer type, highway or city, load, and countless others.

"That is a challenge for any type of regulation that tries to drive technology on vehicle aspects that are highly variable," Mormino says. "And the way that the regulation attempted to deal with that is that it separated out the most certain aspect, the engine, and provided a much brighter focus on something you can repeatably and accurately measure and do so in a way where it can be enforced."

On the other side of this argument sits DTNA's Sean Waters, as well as the Volvo Group's Tony Greszler.

"Our goal has always been to provide our customers with the lowest total operating costs to increase their revenues, and the most effective way to do that has been to provide better fuel efficiency," says Waters. "Regulations have interfered with this goal in the past where criteria-pollutant emissions control technology had a great negative impact on fuel economy.

"It's critical that regulations to reduce fuel consumption do not in actuality result in negative impacts on real-world fuel efficiency gains, and this is where the current separate engine standard program has failed. Engine test cycles are based on historical operating data and cannot reflect changes in engine size, powertrains, or vehicle power demand and do not accurately represent the fuel used in the real-world, nor were they ever designed to do so," Waters suggests.

"DTNA believes the best way to ensure that the Phase 2 regulation provides a total-cost-of-operation benefit to customers is to give manufacturers the ability to focus on improving the entire vehicle as it operates on the road and in the application for which its customers want to use the vehicle. Any regulation that doesn’t give manufacturers the flexibility to meet it in the manner that works best for our customers, results in vehicles that customers can’t afford, or doesn’t provide sufficient real-world payback and risks creating a pre-buy prior to the regulation becoming effective."

Waters goes further, saying that the tests for criteria pollutants -- NOx and PM -- are based on a test designed in 1990 or 1991 "when trucks had higher horsepower, more torque. It was just a different way of operating an engine. The test was never designed for CO2." Nor was it designed to measure fuel economy, he adds.

He figures the test was used for convenience in Phase 1 to get a rule done quickly.

At Volvo Group North America, Tony Greszler is vice president of government and industry relations, and he's the point man on Phase 2 rules.

"The bottom line here is that the engine test doesn't test the engine the way it runs in the truck," he says. "It's impossible for any engine test to do that. And it also doesn't account for the impact of the engine on the rest of the truck.

Waste-heat Recovery

"The technology of most concern is what we call waste-heat recovery," Greszler goes on.

It's a tool that Cummins expects to deploy in 2020 or so, though Brian Mormino says some customers may get field-test units in 2017 or 2018. In fact all engine makers are developing it, and a variation is even used in today's Formula One race cars where they add it to the standard V6 and call the package a hybrid. It recovers exhaust heat and turns it back into energy.

"It's essentially a second engine," says Greszler. "And it requires that you run the exhaust heat through a fluid, via a heat exchanger in the exhaust, and run it through an expansion machine to make power, and then condense that fluid again. Which means that you've got a lot more cooling demand. You've now got to cool most of the heat from the exhaust, because the process isn't very efficient, so most of that heat ends up in your condenser.

"And we end up having to add substantial weight, space, and cooling capacity into our trucks," he continues, "which means that we lose aerodynamic performance and we lose freight capacity because of weight. So we add efficiency to the engine but we take it away from the truck. That doesn't make sense.

"Why would you force us to do something like that? Give us the flexibility to look at the truck as a complete entity and make the best, most cost-effective decisions about how to improve the fuel efficiency in a way that meets the target," Greszler urges.

"I think it's also obvious that a system like that adds a lot of components, a lot of sensors, a lot of complexity, and potentially a lot of unreliability. Which customers don't want or need. And if you're not getting the full benefit from it anyway, you're really kidding yourself when you measure the efficiency of the engine in a test cell where weight, space, and cooling demand are not accounted for at all."

Waste heat recovery is just an example, of course, and there might be any number of similar examples that could come up in the future.

"A particular customer could well benefit from efficiency improvements that have nothing to do with the engine and hit the overall targets that EPA will establish," Greszler continues. "Are we going to force him into engine efficiency solutions that don't necessarily match his operational requirements because EPA structured a rule that said X amount had to come from the engine? It just doesn't make sense to us."

Depending on the stringency of the coming rules, and whether or not we have a separate engine test, waste-heat recovery may or may not be needed.

"If we have a fairly stringent engine efficiency requirement measured in a test cell, then WHR may be the only available technology to meet that target," Greszler says. "If it's not applied to the engine but to the truck, we may find quite a few other options.

"We're all developing waste-heat recovery," he adds, "don't get me wrong. I'm not saying it's a technology that shouldn't be explored and exploited when and where it makes sense, but it ought not be forced into production on a time schedule that doesn't allow adequate reliability development and it shouldn't be forced into applications where it doesn't really deliver."

So, much remains to be seen on this topic, and given how much information couldn't be packed into this space, a Part Three seems to be in order. Stay tuned.