As diesel-powered cars begin to make a comeback in this country, there’s growing public awareness that diesel exhaust is clean, really clean. While you may hate the high cost of the emissions systems needed to meet them, Environmental Protection Agency (EPA) standards for diesel engines have resulted in trucks with almost no particulate matter (PM) or NOx emissions, two of the major components impacting air quality. Diesels and the trucks they power have gone from clean-air bad guy to clean-air hero. But if you thought you were done with emissions, think again.
Actually, the next phase of truck emissions regulations has already begun, but it’s gone largely unnoticed because it has been relatively easy to meet and rather than add costs for users like the PM/NOx standards did, it promises significant cost benefits. This new frontier for federal regulation is, as most of you know, greenhouse gas (GHG) emissions. For trucks, that’s carbon dioxide (CO2), and you reduce CO2 emissions by burning less diesel. And who doesn’t want to save fuel?
The first step in mandatory GHG reduction doesn’t kick in until 2014, but truck makers quickly realized that they could reach the required reduction levels largely using existing technologies like wide-base single tires and full aerodynamic treatments, as well as by tweaking engine controls. Since fuel economy sells in the truck market, they all rushed to produce trucks that voluntarily meet the standards with this year’s models. There are some other incentives for manufacturers as well, but the real motivator was delivering something customers value highly.
While this first step has gone well, don’t break out the champagne yet. EPA considers this round of GHG reduction as just Phase One and the 2014 limits as just step one in that phase. The next step, which takes effect in 2017/18, requires another significant GHG reduction. While that will mean even better fuel economy, it also looks like it will require more sophisticated technology, things like waste heat recovery. And whenever you see the term “sophisticated technology” applied to emissions, you know that translates into more dollars.
Whenever you have a Phase One, you know there’s going to be a Phase Two, and EPA isn’t expected to disappoint. It’s hard to predict what the agency will actually do, but it’s believed it will propose those rules in the next year or two with enforcement dates set in the 2020 time frame. Indications are Phase Two will focus on the test cycles used by manufacturers to certify both GHG and PM/NOx emissions and perhaps also require more sensitive onboard diagnostics to ensure trucks stay in compliance.
Some observers have already begun speculating about a Phase Three based on advanced research underway at the National Academy of Sciences, but what those requirements might be is not clear at this point.
Muddying the waters still further, GHG reduction efforts are taking a two-pronged approach with the National Highway Transportation Safety Administration (NHTSA) joining EPA. NHTSA’s contribution is actual fuel economy standards for heavy trucks, which become mandatory in 2016.
Requiring vehicles to be certified for fuel economy levels is quite different than requiring engines to be certified for emissions, but that’s a topic for another time. As is the Dept. of Energy’s Super Truck program, which seeks to improve 2009 tractor and trailer fuel efficiency levels 50% by 2015. And I won’t comment on California’s apparent commitment to cut truck NOx to even lower levels than those we have today.
The one takeaway from this litany of regulatory plans is that despite today’s vaunted clean diesels, you’re not done with tailpipe emissions.