NGV & ABT Treatment in Medium 

and Heavy Duty Truck Rule

15 July 2011

**** EPA Staff Draft - Deliberative **** 1
Agenda

• Crediting of Natural Gas Vehicles

• Structure of Averaging, Banking and Trading 

Provisions
Final Rule NGV Treatment

• NHTSA & EPA have harmonized recognizing NG vehicles 

lower CO2 emissions due to lower carbon content of 

fuel.

• When compared to the diesel and gasoline standards in 

the rule, NG would be expected to achieve 20-30% 

lower CO2 emissions.

• These lower CO2 emissions allow NG engines/vehicles 

to generate a credit against the diesel or gasoline 

based standards.

• Some commenters have suggested using the 0.15 

approach from light-duty for NHTSA portion of the 

program.
Comparing Approaches Side by Side

CO2 Approach 0.15 Approach

Credit Value $4,835 $18,680

CO2 Reduction 

(metric tons) 290 (545)

SCC Benefit ($) $6,385 ($11,986)

Per Tractor Comparison

SCC Benefit ($) $6,385 ($11,986)

Fuel Savings 

(gallons) 130,740 33,839

Energy Security 

Benefit ($) $22,226 $5,753

If as few as 1/3 of Tractors converted to NGVs using the 0.15 incentive 

the entire CO2 reduction of the program would be wiped out.
Final Rule ABT Treatment

• Averaging/Trading among vehicles within the same categories 

(LHD, MHD, HHD), among engines within the same intended 

service class categories (again LHD, MHD, HHD).

• Like vehicles or lik hicles or like engines can a engines can average/trade

• Averaging/Trading restricted between vehicles or engines that 

are significantly different.

– Different weight classes

– Different certification approaches

– Different lifetimes different applications and duty cycles
Why Limit Trading to Like Products?

• Significant uncertainties existing in averaging/trading when credit calculations are 

made based on projections of lifetime use rather than based on actual measured 

performance.

• Uncertainties are lower between like products certified in the same way and are 

higher for vastly different products certified in different ways.

• The greater the uncertainty the more likely actual increases in emissions from 

credit using pr credit using products will oducts will be higher than emission r be higher than emission reductions eductions from credit 

generating products.

• Current ABT structure that matches certification structure 

helps ensure we achieve our environmental and energy 

security goals, maintain a level playing field and avoid 

disruptions to existing market structures.

• ABT structure is critical to support the rule enjoys from a number of industry and 

NGO stakeholders.
Different Solutions for Different Segments 

Make Credit Trading Problematic

full-size pickup 

trucks & work vans

• HD Pickup Trucks and Vans

• certified on chassis test as complete vehicle

• use pattern varies greatly from recreational to 

daily towing services

• Semi Tractors

• certified in pieces with purposeful disconnect between 

Semi 

Tractors

vocational vehicles

• certified in pieces with purposeful disconnect between 

engines & tractors

• engines certified in engine test cell

• tractors certified using a model

• aerodynamics tested using OEM methods

• tires tested according to ISO procedure

• weight reduction based on pick list

• use pattern varies but not as significantly as for pickups, 

but loads & terrain do vary significantly

• Vocational Vehicles

• certified in two pieces

• engines using engine dynamometer

• trucks based on model & ISO tire test

• tire threshold met by large number of tires today