GHG Standards, Tier
4 Continue To Keep
Things Interesting
BY W. ADDY MAJEWSKI
We have just witnessed the adoption of the first green- house gas (GHG) emissions and fuel economy regulations
that will shift the engine development focus toward CO2 and energy efficiency — at least in highway
engines. In August, the U.S. EPA and
the NHTSA finalized GHG and fuel-efficiency standards for heavy-duty
trucks — the first-ever fuel-efficiency
regulations for heavy vehicles in the
United States and some of the first
in the world (notably, ahead of the
European Union, which likes to be
seen as the world’s leader in GHG
emissions reduction).
The standards apply to model-year
(MY) 2014-2018 medium- and heavy-
duty vehicles, from semi trucks to the
largest pickup trucks and vans, as
well as all types and sizes of work
trucks and buses in between. The
standards are rather complex, with
different sets of limits for combina-
tion tractors, vocational trucks and
heavy-duty pickup trucks and vans.
W. Addy Majewski is president
of Ecopoint Inc., an engine emissions consultant in Mississauga,
Ontario, Canada. Ecopoint also
operates DieselNet an Internet
site dedicated to diesel emissions issues. DieselNet can be
accessed through the Emissions
Data Center at Diesel Progress
OnLine, www.dieselpub.com or
at www.dieselnet.com.
tire rolling resistance, the presence of
idle-reducing technology and vehicle
speed limiters.
In the heavy-duty pickup trucks and
vans category, different standards have
been adopted for diesel and gasoline vehicles. The average per-vehicle
improvement in fuel consumption is
15% for diesel and 10% for gasoline
vehicles, compared to a common baseline. Compliance is determined through
chassis dynamometer testing, similar to
the procedures for light-duty vehicles.
Increasingly more challenging GHG
emissions standards also apply to
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