### STATEMENT OFTHE ADVANCED ENGINE SYSTEMS INSTITUTE ON THE PROPOSAL BY THE U.S. ENVIRONMENTAL PROTECTION AGENCYAND THE NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION TO SETPERFORMANCE STANDARDS FOR GREENHOUSE GAS EMISSIONS FROMMEDIUM- AND HEAVY-DUT VEHICLES

- PHASE 2 DOCKET ID NO. EPA-HQ-OAR-2014-0827; NHTSA-2014-0132 AUGUST 18, 2015 My name is Mona Sheth, I amhere on behalfofthe Advanced Engine Systems Insti (AESI) to provide comments on the agencies' proposal to set more stringent greenhouse gas standards for medium- and heavy-duty vehicles.
AESI represents several emissions control and efficiencytechnology manufacturers i an industry employing more than 65,000 people in the U

.S. Formore than 40 years, our indust has been working with vehicle manufacturers

- ourprimary customers

- and the regulators to deve op technologies to reduce harmful pollution in the most cost-effective ways possible.
The industry's many innovations developed and deployed in the U.S., in response to science-driven air quality regulations, have reduced pollution from cars and trucks bymore th n 75% since 1975. This has occurred even while vehicle miles traveled increased 300%, drivin economic growth forward and significantly enhancing mobility.
We commend the Agency and the President for going beyond the public health and environmental impacts ofcriteriapollutants like particulate matter (PM) and nitrogen oxides (NOx) to tackle the grave risks associated with greenhouse gas and black carbon emissions. Carbon pollution from the U.S. transportation sector, especially medium- and heavy-duty vehicles, is a very significant contributor to global atmospheric concentrations and will rise through 2040 without Phase 2 orsimilar limits.
AESI is pleased that the Agencyhas proposed to retain the basic regulatory structure sed in Phase 1, including a separate engine standard and similartesting and certification procedur

.s. Our industryhas invested heavily in research and systems to deliver cost-effective greenhous gas reductions to meet the Phase 1 schedule while meeting the 2010 standards for NOx and P

. Retaining a separate engine standard and enhancing compliance enforcement will help ensure he long term environmental integrity ofthe program. AESI supports setting final Phase 2 greenhouse gas standards that will strongly encourage innovative companies to develop new technologies and systems that canhelp vehi le and engine makers to quickly, cost-effectively, and reliably reduce or eliminate carbonpolluf n and still overperform on criteriapollutants. We appreciate the delicate balance that the agenc es must consider between setting an engine standard that appears feasible now versus setting a slightly more stringenttechnology-driving standard that will prompt faster evolution, more reductions and greater consumer savings inthe long run. There appears to be ample evidence to indicate that Alternative 4's timeline comes cl sest to striking the right balance, though it does seemthat greater reductions than the 4.2% target 

### i the proposal could well be technically feasible and still quite cost-effective. There are now amultitude oftechnologies, including waste heat recovery, turbo-compounding, advanced downspeeding, hybridization, etc. that canbe ready to deploy inthat timeframe or sooner at s ll reasonable cost, provided the right policy or market signal or some combination ofincentives r credits

. The agencies may want to consider incentives or credits, particularly in an era oflow fuel prices, to expedite the commercialization ofthese technologies and earlier and more costeffective achievement ofthe program goals.
Our members have been working with the Department ofEnergy's Super Truck progr m to demonstrate the magnitude ofcarbon dioxide reductions that engine and vehicle technologi s can deliver while improving criteria pollution control systems. Through thatprogram and the investment our companies are making with EPA and the California Air Resources Board at th Southwest Research Institute project, we are increasingly confidentthat there is a fuel economy /greenhouse gas optimization "bonus" that can be realized by integrating rapidly emerging and cost-effective NOx control strategies into heavy-duty manufacturers' engines a powertrain designs. There no longer needs to be the once evident tradeoffbetween engine efficiency and tailpipe NOx emissions. However, without clearpolicy signals, those NOx controls may languish and leave significant fuel economy gains on the table. California is seriously considering an additional 90% reduction inNOx emissions beYi nd the 2010 standards for medium and heavy duty vehicles

. Should California, the Ozone Trans ort Commission states or EPA choose to adopt such a standard, AESI members will work with ou customers to ensure that that standard can be achieved and to realize the optimization "bonus" and make fuel economy /greenhouse gas targets easier to achieve

. AESI supports the Agency's efforts to tighten the nitrous oxide (N20) cap to ensure th t efficiency enhancements made by engine manufacturers to reduce carbon dioxide pollution d not lead to unintended increases ofthis potent greenhouse gas. Meeting the proposed cap will be challenging, but our members are already working on the cutting edge materials necessary to limitN20 formation. Finally, though the agencies' proposal does not seekto place limits onthe large

**vol ~**  ofblack carbon emissions from heavy-duty engines, itis worth noting that the global

**warrni~** potential ofthis pollutant is very significant, as high as 4,470 times that ofcarbon dioxide

. T Agency may want to consider incentives in this rule or another for the rapid installation of particulate filters on any vehicles/engines not already using them, as the filters can remove 99 % ofblack carbon from exhaust streams. Thankyou for the opportunity to provide comments today

. We will supplement these remarks with additional written material before the end ofthe commentperiod.