The trucking industry and congressional Republicans are fighting a new EPA regulation aimed at reducing smog-forming emissions from heavy-duty trucks — a mandate that is likely to significantly increase costs for big rigs and for shipping in general.

And an upcoming separate rule aimed at mitigating greenhouse gases from the same vehicles could complicate matters further because the technologies for reducing smog and carbon emissions might not be compatible.

The EPA’s nitrogen oxide (NOx) rule, finalized in December and taking effect later in March, requires heavy- and medium-duty vehicles starting in model year 2027 to meet the “most stringent” emissions reduction option first proposed by the agency a year ago.

The new rules have triggered an outcry from small-fleet truckers that echoes their response when EPA last tightened emission standards for big trucks 12 years ago.

“We went through all of this in 2011,” said Lewie Pugh, longtime trucker and executive vice president of the Owner-Operator Independent Drivers Association, which represents small businesses and professional truck drivers. “Back then, there was a $20,000 price increase on this technology … and there was more trouble with those trucks than before. It pushed thousands of small truck drivers out of business.”

Nitrogen oxides are produced from fuel burning and mix with other pollutants in the atmosphere to create smog and acid rain. High levels of smog have been linked to respiratory diseases and asthma.

The EPA estimates that the rule will reduce NOx emissions from the heavy-duty truck fleet by 48 percent by 2045. If the most ambitious goals outlined in the rule are met by 2045, the EPA projects that early onset asthma cases among children will decline by 18,000 per year and premature deaths will go down by 2,900 annually.

Truckers opposed to the rule have support from 35 Republican senators who back a joint resolution that would overturn it, arguing that it “incentivizes operators to keep using older, higher-emitting trucks for longer” and “would jack up vehicle costs and hurt good paying jobs,” said sponsor Sen. Deb Fischer, R-Neb.

The resolution is Republicans’ third introduced in one or both chambers under the Congressional Review Act in the 118th Congress seeking to roll back Biden administration environmental rules, according to the National Conference of State Legislatures. Under the CRA, a petition signed by 30 or more senators can lead to a nondebatable motion to proceed to its consideration, and the motion cannot be filibustered. But even if the resolution passed the Senate, President Joe Biden would almost certainly veto it, and a two-thirds majority would be required to override.  

The cost question

Although the rule outlines what kind of updates manufacturers will have to make to meet the standards, the question of how much it will cost truck producers and operators is still up in the air. 

EPA has estimated that the final program could cost an extra $8,304 per vehicle for a long-haul truck with a heavy diesel engine. But many in the industry argue the agency’s estimates tend to be on the lower side — a market analysis by the industry group American Truck Dealers found that the cost of NOx regulations issued by the EPA in 2001 was more than $21,000, while the agency estimate was $5,000. 

In the new rule, the agency included mandates aimed at helping small-fleet truckers with some of the costs — like an extended warranty on the new technology to ease the burden of repairs and requirements that manufacturers build the technology to last up to 800,000 miles, an increase from EPA’s past 435,000-mile standards. 

But the industry might not be able to pin down a total cost estimate until closer to 2027, said Allen Schaeffer, executive director of diesel equipment trade group Diesel Technology Forum. 

“All of the guarantees of the robustness of the system and the warranty coverage behind it — that’s where the economics and the costs come in,” he said. “This means that second and conceivably even third owners would be buying a used truck that still had some warranty coverage on the emissions control components.”

Climate impacts

The cost question is expected to get more complicated, Schaeffer said, as EPA is looking to propose rules setting greenhouse gas emission standards for heavy-duty trucks. 

Some manufacturers argue that lowering both NOx and carbon dioxide emissions might not be technically feasible, Schaeffer noted.

“Most anything that you do in the engine to reduce NOx emissions will have the adverse effect of increasing carbon dioxide emissions — the laws of thermodynamics and physics are what they are,” he added. “The reality is that if you make the NOx standards so low, then you might have to worry about whether or not you’re going to be able to meet a greenhouse gas requirement.”

Swedish company Volvo echoed those concerns in its comments on the proposed emission rule, stressing that “NOx reductions are always paid for with CO2” and that the NOx standard will “limit current and future potential CO2 gains.” 

EPA stated in the final NOx rule that its testing has not projected an increase in greenhouse emissions resulting from compliance with the final standards. But German manufacturer Daimler Truck said in its comments that EPA’s low-NOx demonstration and investigations “ignore the complexities of CO2-NOx emission trade-offs” and “ignore the increased backpressure from low-NOx demonstration-related hardware, which will further harm [greenhouse gas] performance.”

Regardless, environmental groups are still pressing EPA to adopt the most stringent standards for greenhouse gases. Considering that Biden has made tackling emissions from the transportation sector one of his key climate goals, truck manufacturers see the NOx-CO2 tradeoff in their futures.

“When we do these things, they all sound really good on face value, but we never look at the unintended consequences of these items,” said Pugh of the independent truckers group. “Even if you have a good extended warranty, the problem is if you’re broken down, say, three days each month, that’s time that you’re not working and not making money.”

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