Introduction of new technology clean diesel truck engines and emissions control systems into the nation’s trucking fleet over the last five years is now at a 30% level and has yielded significant emission reductions and substantial fuel savings, according to research commissioned by the Diesel Technology Forum.
“Almost three million heavy-duty diesel commercial vehicles introduced in the U.S. from 2011 through 2016 now on the road [are] powered by the latest generation clean diesel engines, and these trucks have delivered important benefits in the form of cleaner air, fewer carbon dioxide emissions and dramatic fuel savings. Over a five-year period, the newest generation commercial vehicles have saved 4.2 billion gallons of diesel fuel, and reduced 43 million tons of carbon dioxide (CO2), 21 million tons of oxides of nitrogen (NOx) and 1.2 million tons of particulate matter,” said Allen Schaeffer, executive director of the Diesel Technology Forum, a non-profit organization in Frederick, Md., that promotes diesel engines, fuel and technology.
Because diesel overwhelmingly dominates the heavy-duty truck sector and is also the number one power source for medium-duty vehicles, the transition to newer generations of clean diesel technology (2011 and later MY) is significant, Schaeffer said in a July 13 statement issued by the Forum. The 30% national average is up from 25.7% last year, Schaeffer said. The research also estimated that significant further benefits would accrue to communities across the country if more of the newer generation clean diesel trucks enter into service.
The research was conducted by HIS Markit, a technical marketing research firm. State rankings data are based on Diesel Technology Forum (DTF) analysis of IHS vehicles-in-operation data representing Class 3-8 diesel trucks from model year 2011 through 2016 in 50 states and the District of Columbia through Dec. 31, 2016, the Forum said.
“The U.S. trucking fleet is transitioning to newer clean diesel technology which means immediate fuel savings, lower greenhouse gas emissions and cleaner air. “This newest generation of clean diesel trucks have NOx emissions that are 99 percent lower than previous generations along with 98 percent fewer emissions of particulate matter, resulting in significant clean air benefits throughout the U.S.,” Schaeffer said. Beginning in 2011, all heavy-duty diesel trucks sold had to meet NOx emissions of no more than 0.20 grams per brake horse-power hour (g/BHP-hr.), Schaeffer noted. This is in addition to particulate emissions levels of no more than 0.01 grams per brake horse-power hour (g/HP-hr.) established in 2007, he said.
“Achieving these substantial emissions reductions and efficiency advancements was in part the result of collaboration of the nation’s leading truck and engine manufacturers working with the Department of Energy and 21st Century Truck Partnership’s ‘Super Truck’ program,” said Schaeffer. “While the intent of this valuable program is to push the margins of research engineering efficiency, it is clear that demand is leading many of these strategies to be integrated into the commercial truck fleet and contributing to real-world emissions reductions and fuel savings.”
“In addition to these substantial societal benefits, a Class 8 tractor-trailer sized vehicle powered by the latest generation clean diesel engine will save the owner 960 gallons of fuel each year, relative to the previous generation of technology. When these benefits are compounded over the entire population of the clean diesel fleet, the 4.2 billion gallons of fuel saved between 2011 and 2016 is equivalent to almost 40 percent of the strategic petroleum reserve,” said Schaeffer.
To achieve these new levels of emissions and efficiency performance, Schaeffer said, the new clean diesel system relies on an efficient engine and optimized combustion system utilizing advanced fuel-injection, turbocharging and engine management strategies coupled with advanced emissions controls and after-treatment technologies including particulate filters and selective catalytic reduction (SCR) systems, all running on ultra-low sulfur diesel fuel.