Robert L. Greco, III Group Director: Downstream and Industry Operations

1220 L Stree t, NW Washington, DC 20005

- 4070 USA Telephone 202

- 682

- 8167 Fax 202

- 682

- 8051 Email greco@ api.org www.api.org

October 24, 2013

Air and Radiation Docket and Information Center Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Avenue, NW. Washington, DC 20460

Re: Docket ID No. EPA

- HQ

- OAR

- 2011

- 0135

Supplemental Comments of the American Petrole um Institute on the U.S. Environmental Protection Agency’s Proposed Ru le on Control of Air Pollution f rom Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards

Submitte d via email to a
- and

- r
- docket@epa.gov

The American Petroleum Institute (API) recently became aware that the Manufacturers of Emission Controls Association (MECA) submitted “supp lemental” comments to the EPA Tier 3 Rulemaking Docket that were critical of comments which we had filed jointly with the American Fuel and Petrochemical Manufacturers (AFPM) on June 28, 2013 concerning the Tier 3 Notice of Proposed Rulemaking (NPRM). 1 Specifically, MECA stated that the intent of its submittal was:

“... to provide additional information and comments on four important topics: 1) the importance of 10 ppm average sulfur gasoline to meeting proposed Tier 3 emission limits; 2) the synergy betw een ultra

low sulfur gasoline and the introduction of cost effective, lean

- burn, gasoline direct injection technology with improved fuel consumption; 3) costs associated with Tier 3 compliance on gasoline light

- duty vehicles; and 4) harmonization with ARB’ s 1 mg/mile LEV III PM standard.”

In this submittal, MECA attempts to rebut the API/AFPM written comments concerning: (a) EPA’s inadequate justification of a technical need for a 10 ppm gasoline S standard, and (b) the future market penetration prospec ts for lean

- burn GDI technology in the US light

- duty vehicle fleet.

The supplemental comments from MECA are based upon very limited data that have not been independently validated and that were generated using test fuels with potentially confounded prop erties. In addition, MECA’s outlook for lean

- burn GDI technology in the US ignores the real

- world experience of this technology in the European and Japanese markets where 10 ppm gasoline sulfur regulations have been in place. Our detailed response rega rding each of these topics is further elucidated below.

1 Docket ID No. EPA

- HQ

- OAR

- 2011

- 0135

### Page 2

Technical Need MECA completely misses the point which API and AFPM were attempting to make with respect to the use of emission control technologies with lower sulfur sensitivity to reduce cold

- start emissions in order to comply with the proposed Tier 3 standards. MECA asserts that API and AFPM “...assume that the use of three cold start emission control technologies [hydrocarbon adsorbers, reduced thermal mass substrates and exhaust piping, and secon dary air injection] ...could be used to completely eliminate cold

- start emissions with today’s gasoline sulfur levels.” This assertion takes the API and AFPM comments completely out of context. If one were to read our comments in their entirety, one would note that we never stated that these three technologies had zero sulfur sensitivity, nor did we assume that they would be used to completely eliminate cold start emissions with today’s gasoline sulfur levels. Rather, we noted that cold

- start technologies “ are not likely to be very sulfur sensitive ” and that “... if manufacturers could completely eliminate cold

- start emissions, the current level of catalyst technology would allow compliance with the Tier 3 standards” primarily because “warmed

- up emissions

are already at a level that is compatible with the standard.” A full rendition of our comments on this point follows (from p. 20 of our detailed comment submittal):

“The three technologies listed above are designed to reduce or eliminate emissions that occur during the early period of operation, when the engine is cold and the catalyst has not yet reached operating temperature. If these technologies are employed to provide the bulk of the reduction necessary, then clearly the need for sulfur reduction is les sened. Unfortunately, it appears EPA did not consider or even discuss this possibility. These listed technologies are exclusive of changes in engine design that EPA expects could and would be made to achieve compliance, and which are also not sensitive to gasoline sulfur levels.

Figure 2 shows that if manufacturers could completely eliminate cold

- start emissions, the current level of catalyst technology would allow compliance with the Tier 3 standards. Furthermore, given that cold

- start emissions and cold

- start emission control technologies are not likely to be very sulfur sensitive, little or no reduction in gasoline sulfur content should be required to achieve compliance. While it is unlikely to be able to eliminate this source of emissions fully, the t able clearly shows that warmed

- up emissions are already at a level that is compatible with the standard, which again calls into question the need for additional reduction in gasoline sulfur content and EPA’s arbitrary selection of the proposed 10 ppm limit . Regardless, it is clear that EPA should have identified the possible emission control steps that are sulfur sensitive and those that are not sulfur sensitive, and evaluated whether 10 ppm sulfur was necessary and cost effective.”

MECA relies heavily o n an SAE paper authored by Ball, Clark and Moser (Umicore) 2 in attempting to rebut our argument that there are sulfur

- insensitive automotive technologies available today that could be used to facilitate compliance with the proposed Tier 3 emissions standar ds without the need to reduce average gasoline sulfur content to 10 ppm. This SAE paper had reported measurements of the FTP NOx emissions response of a 2009 model year Chevy Malibu PZEV to test gasolines with sulfur contents of 3 ppm and 33 ppm.

In r eply to MECA, we reiterate concerns which API and AFPM had raised in a critique of the Umicore SAE paper provided in our June 28, 2013 written comments on the Tier 3 NPRM and also in an earlier November 11, 2011 API response to the AAM proposal to cap gasoline sulfur content at 10 ppm. Specifically:

 The SAE paper fails t o note the differences in the underlying properties of the base fuel used and how this may confound the results. Specifically, when comparing a CARB Phase II certification fuel (33 ppm sulfur) with a EEE

- Lube certification gasoline fuel (“zero sulfur”), d ifferences in distillation properties, chemical

2 Ball, D., Clark, D., and Moser, D., "Effects of Fuel Sulfur on FTP NOx Emissions from a PZEV 4 Cylinder Application," SAE Technical Paper 2011

- 01

- 0300, 2011, doi:10.4271/2011

- 01

- 0300. Note that the MECA Supplemental comments include an incorrect (2013) date citation to the SAE publication number for this paper.

### Page 3

composition and oxygenates can impact emissions results. The standard industry practice is to use sulfur dopants to avoid underlying base fuel changes impacting the emissions.

 Results from testing two fuel s on a single vehicle do not provide much guidance on the potential impact of fuel sulfur levels on the fleet of future Tier 3 vehicles. 

### In particular, the Umicore paper did not provide a statistical analysis to show whether the measurements made on the s ingle vehicle tested were (a) statistically significant and/or (b) broadly characteristic of the underlying technology represented.

Market Penetration of Lean

- Burn GDI Technology MECA asserts that lean NOx adsorber catalysts are the preferred strategy for reducing NOx on lean GDI light

duty engines and claims that 10 ppm sulfur gasoline is necessary for the use of this technology in the U.S. However, MECA does not explain why lean

- burn GDI technology failed to enter the European and Japanese markets in si gnificant volumes after these two regions adopted 10 ppm gasoline sulfur standards. (i.e., market penetration of lean

- burn GDI peaked at ~2% and has since been declining.) MECA also alludes to two European OEMs who want to introduce this technology into t he US market. Given the relatively low US gasoline light

- duty vehicle market penetration by European OEMs, combined with the relatively high incremental cost of this technology, MECA’s comments do not contradict an analysis performed by the Martec Group 3 which estimates that the market opportunity for lean

- burn GDI is limited to at most ~3% by 2020.

We further note that the Agency agreed with Martec’s evaluation of lean

- burn GDI technology in its regulatory impact assessment conducted for the final rulema king, “2017 and Later Model Year Light

- Duty Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy Standards.” Specifically, the EPA did not use lean

- burn GDI in the vehicle technology packages that were evaluated for that rulemaking as it was found less cost effective than other available technologies. In short, the Agency agreed with API’s comments on this issue. 4

In summary, the supplemental comments from MECA are based upon very limited data that have not been independently validated a nd that were generated using test fuels with potentially confounded properties. In addition, MECA’s outlook for lean

- burn GDI technology in the US ignores the real

- world experience of this technology in the European and Japanese markets where 10 ppm gasol ine sulfur regulations have been in place.

Please contact David Lax at (202) 682

- 8479 if you have any questions concerning the above submittal.

Sincerely,

Robert L. Greco, III

3 McMahon, K.B., Selecman, C., Botzem, F., and Stablein, B., “ Lean GDI Technology Forecast: The Impact of Ultra

- Low Sulfur Gasoline Stan dards ,” Society of Automotive Engineers Technical Paper Series, Paper No. 2011

- 01

- 1226, 2011
4 See: 2017 and Later Model Year Light

- Duty Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy Standards: EPA Response to Comments , EPA

- 420

- R

- 12

- 0 17, August 2012), p. 12

- 32, available here