Comments on Tier 3 LDV NPRM

8/22/2019 Comments on Tier 3 LDV NPRM

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ICCT Comments in Response to the Proposed Rulemaking Issued by theEnvironmental Protection Agency on Control of Air Pollution from Motor

Vehicles:Tier 3 Motor Vehicle Emissions and Fuel Standards

Docket ID No. EPAHQOAR 20110135

July 1, 2013

These comments are submitted by the International Council on CleanTransportation (hereafter, ICCT). The ICCT is made up of leading governmentofficials and experts from major countries and regions around the world who participateas individuals based on their experience with air quality and transportation issues. TheICCT promotes best practices and comprehensive solutions to improve vehicleemissions and efficiency, increase fuel quality and sustainability of alternative fuels,reduce pollution from the in-use fleet, and curtail emissions of local air pollutants and

greenhouse gases (GHG) from international goods movement.

Overall Summary

The ICCT strongly supports the proposed Tier 3 standards and commends EPA fortaking the proposed steps to improve public health. The standards will maintain U.S.leadership in light duty vehicle emission control and allow the US to catch up to Europeon gasoline fuel quality. Not only will the requirements improve public heath in the US,they will help accelerate introduction of inexpensive emission controls in other countries.We applaud EPA, along with the California Air Resources Board, for taking another long

step along the road to a sustainable transportation system.

While there are a few areas in which the rule could be improved, overall the provisionsare reasonable. The costs to comply are modest and likely overstated by EPA. Thefeasibility of the proposed Tier 3 standards has already been demonstrated by thenumerous vehicles that already meet the California LEV III standards and Tier 2 bin 2standards. The two keys to low emissions are precise air/fuel control and rapid catalystlight-off. Since the Tier 2 standards were adopted there have been major improvementsin both of these areas, making compliance with the proposed Tier 3 requirementseasier.

The ICCT also commends the EPA for proposing to reduce gasoline sulfur to 10 ppm.Japan and South Korea have required 10 ppm sulfur in gasoline since 2007 and Europesince 2009. Even Chile has required 15 ppm sulfur in gasoline since 2010. Given theleadership shown by the US in most environmental areas, it is important for the US tocatch up on gasoline sulfur.


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Our comments focus on ensuring that the final rule is as robust as possible. We havetwo primary objectives: first, to help ensure that the most robust cost information is usedfor vehicle emission control technology and reducing sulfur in gasoline; second, tosuggest improvements to the proposed SFTP standards and the adoption of E15certification fuel, which have the potential to reduce the overall effectiveness of EPA's

programs. We also offer a number of comments on the heavy-duty provisions, futureFTP particulate standards, and some of the procedural issues.

A summary of all of our comments on the proposed rule, followed by additional detail oneach item:

1. Major advancements have occurred in vehicle emission control technology.Catalysts have improved dramatically, fuel injection is more precise, feedback ofactual air/fuel ratio is faster, software algorithms to predict air/fuel ratio haveimproved, and drive-by-wire systems allow air and fuel to be changedsimultaneously. Further, development of initial idle retard for cold starts can bringthe catalyst above light-off temperature before the initial 20-second idle is done.As these and other improvements are primarily due to better software algorithms,meeting the vehicle standards will be easier and will cost much less thanassumed in the proposed rule. ICCT's analyses found that catalyst preciousmetals will cost only about a third as much as estimated in the draft RIA andOptimized CC Catalyst, Optimized Thermal Management, Secondary AirInjection, and Hydrocarbon Adsorbers will not be needed on the vast majority ofvehicles or will cost much less than estimated in the draft RIA.

2. The cost of reducing gasoline sulfur from 30 ppm to 10 ppm is very modest. TheICCT contracted with MathPro in 2011 to evaluate the cost of reducing sulfur

from 30 to 10 ppm. MathPro found that the cost would be 0.8 to 1.4 cents pergallon, and these results are likely to be conservative.3. The SFTP standards are too lenient and, as proposed, will not be effective.

Current vehicles certified to Tier 2 bin 2 or LEVII-SULEV have averageNMHC+NOx emissions of less than 10 mg/mi, more than 80% below theproposed limit of 50 mg/mi in 2025. Similarly, the proposed SFTP particulatestandards are 3.3 times higher for vehicles < 6000 GVWR and 6.7 times higherfor vehicles > 6000 GVWR than the proposed FTP standard. Setting the SFTPstandards properly is especially important for diesel engines, as diesel emissioncontrol hardware requirements are largely set by the high load conditions on theSFTP. SFTP NMHC+NOx standards should be set at no more than 20 mg/mi and

SFTP particulate standards at no more than 6 mg/mi.4. While the ICCT supports using a more representative fuel for certification testing,

E15 is not representative of in-use fuel. E15 can cause damage if it is used insmall engines or in legacy vehicles. E15 is also specific to ethanol, whichencourages the use of food feedstocks instead of more environmentally friendlyfeedstocks. Finally, E15 provides significant evaporate cooling, whichmanufacturers could exploit to generate higher fuel economy on the tests than


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the vehicles actually experience in use. The ICCT recommends that the test fueluse E10.

5. The ICCT has similar concerns on any future use of engines using E30. Inaddition, we are concerned that E30 could open the door to E30 credits againstthe CAFE and GHG standards, similar to what has already occurred for FFVs. It

would be much better for EPA to focus on increasing the octane rating of allgasoline.

6. The ICCT supports maintaining fuel-neutral criteria emissions standards forheavy-duty vehicles. We also fully support extending chassis-based emissionrequirements to all complete vehicles up to 14,000 gross vehicle weight andextending the supplemental FTP requirements to complete vehicles between8,500 and 14,000.

7. The ICCT supports updating the R-factor in the carbon balance equation for NHVchanges. Specifically, the R-factor determined by ORNL for Tier 2 vehicleswithout the data outlier should be used, or R=0.96.

8. A key concern for natural gas vehicles is the atmospheric venting of natural gasthat occurs during refueling. It is very important that this venting of natural gas becontrolled and recaptured. The ICCT recommends that EPA develop and adoptrequirements for refueling emissions from all gaseous-fueled vehicles.

9. The ICCT recommends that EPA harmonize with both the CARB 1 mg/mileparticulate mass standard starting with 2025 and the European particulatenumber standards. Currently, both requirements are hindered by the lack ofmeasurement precision, but continuing research into particulate measurementshould resolve these issues in the future.

1) Vehicle Emission Control Cost AssessmentsThe adoption of more stringent standards usually requires the improvement of currenttechnologies or the adoption of new ones. This results in additional cost tomanufacturers and the public. It is frequently difficult to assess the cost of improvedtechnology, as manufacturers regard cost information as confidential for competitivereasons.

As emission control technology cost estimates had not been updated in 10 to 15 years,the ICCT conducted a study to update emission control costs, published last year.1 Costestimates were conducted for the main emission control technologies, using updated

assessments of technology actually being used, impacts of learning as manufacturingvolumes increase, and technology improvements that have made the systems simpleror more efficient.

1EstimatedCostofEmissionReductionTechnologiesforLight-DutyVehicles,ICCT,March2012.http://theicct.org/estimated-cost-emission-reduction-technologies-ldvs


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ICCT reviewed the emission control cost estimates in the draft RIA and compared themagainst the results of our study. Our review indicates that, for some technologies, recentcost reductions were not accounted for in the proposed rule. It appears that EPA isusing outdated and overstated cost estimates in many cases. Following is ICCT'sassessment of the direct manufacturing cost estimates in Table 2-5 from the draft

Regulatory Impact Analysis (RIA), reproduced here as Table 1.

Table 1. 2017MY Incremental Technology Direct Manufacturing Costs by GasolineEngine Type (2010$)

TECHNOLOGYGASOLINE ENGINE TYPE

I4 V6 V8 HDV8

Catalyst loading (PGM) $61 $81 $101 $51

Optimized CC Catalyst $20 $40 $61 $61

Optimized Thermal management $30 $30 $30 $30

Secondary Air Injection NR $101 $101 N/R

Engine Calibration $2 $2 $2 $2

Hydrocarbon Adsorber NR NR $152 NR

Evap. Emission control $17 $17 $17 $17

NR: Not required

Catalyst Loading (PGM)

Table 2-5 in the draft RIA shows that the incremental direct manufacturing costs forcatalyst loading, Precious Group Metal Loading (PGM), from Tier 2, range from $61 fora 4-cylinder engine to $81 for a V8. However, ICCT's 2012 study found that precious

metal loadings have been dramatically decreasing over time. For example, a 4-cylinder2.0 L vehicle meeting Tier 2 standards only had $71 of precious metals total. While theproposed rule did not specify the assumed percent increase in precious metal loadings,it is clear that EPA is overestimating the cost of additional catalyst loadings compared totoday's applications.

One of the main reasons for manufacturers to avoid high PGM loading is the high andextremely volatile cost of precious metals. PGM market price data is presented inFigure 1. The annual average market price of Pt has escalated from about $12/g in1992 to about $52/g in 2010. Rh prices reached prices above $200 per gram in 2008,and fell to $79 in 2010. The volatility of precious metal prices is due, in part, to the

inelastic supply of Rh and Pd. While it is possible to increase Pt mining in response toadditional demand, Rh and Pd are largely byproducts of Pt and nickel mining and it isnot economical to increase mining just for additional Rh and Pd.


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Figure 1 PGM annual average market price, nominal values. From: PlatinumToday

Thus, the market has driven manufacturers to keep working on methods to reduce PGMloading without having any impact on catalyst effectiveness or durability. ICCT's 2012report assessed the precious metal reductions that have occurred though about 2010.Table 2 summarizes ICCT's assessment of the amount of precious metal loading usedby 2010 vehicles meeting Tier 2 emission standards. This table assumes that thecatalyst volume is equivalent to engine size. This assumption is consistent with thegasoline automotive catalyst literature, which varies between 0.8 and 1.1. Also, note

that PGM prices used for Table 2 have been updated from ICCT's 2012 report and usethe average price during one year (June 2012 May 2013).

Table 2. Cost of PGM loading for catalyst used in Tier 2 gasoline vehicles

TIER 2LOADING

PGM PRICEPGM COSTPER LITER

PGM COST PER VEHICLE

g/L $/g $/L I-4, 2.0L V-6, 3.0L V-8, 4.0L

Pt 0.1 $50 5.0 $10 $15 $20

Pd 1.6 $22 35.2 $70.4 $105.6 $140.8

Rh 0.1 $39 3.9 $7.8 $11.7 $15.6Total Costs 44.1 $88.2 $132.3 $176.4

The annual vehicle emission control technology review by Tim Johnson of Corning, arenowned international expert on automotive catalysts, estimates that Tier 2 PGMloadings have been reduced by 70% from Tier 1 levels, even thought emissions have


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dropped by more than 90%.2 This supports the PGM loadings in Table 2, if notsuggesting that the loadings in Table 2 are conservative.

In addition, a summary of recently published SAE papers on automotive catalystdevelopments is presented below. These papers demonstrate that additional reductions

in precious metal loadings are expected in the future and that a 30 mg/mile NMOG+NOxwould not require a large increase in precious metal loadings.

Rohart et al. studied how new materials can be used to reduce PGM loading on TWCapplications.3 A brief introduction to TWC technology presented in their report helps thereader understand the evolution of materials for better performance. The firstgenerations of TWC relied on a simple mixture of ceria and PGMs; while now zirconia isadded to achieve better OSC performance under severe temperature conditions. Ceria-zirconia mixed oxides materials achieved widespread adoption in TWCs by the 1990s.High thermal stability demanded by closed coupled catalyst is a key property ofZirconium based materials.

Researchers from Honda and Johnson Matthey demonstrated that precious metalusage could be reduced by 25% with respect to current Tier 2 Bin 5 catalysts whilesimultaneously lowering emissions to meet the new California LEVIII SULEV30standard, using an improved layered catalyst.4. Their design is based on a Pd onlycatalyst for the close-coupled (CC) position and a Pd/Rh improved catalyst for theunderfloor (UF) position. This design demands S


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Figure 2 Emission test results with respect to (a) FTP target and (b) SFTP targetfor LEV3 SULEV30 and 25% lower PGM loading than current LEV2 PZEV levels[2012-01-1242].

Ball and Moser, of Umicore, studied the emission performance of two PZEV vehicles tounderstand PGM loading of LEVIII vehicles.5 The researcher group evaluated the costincrements due to PGM loading at different emission levels on two PFI models. Theirdata shows that moving from LEV70 (70 mg/mile NMOG+NOx) to SULEV30 (30mg/mile NMOG + NOx) on a 2.4 L PFI vehicle, with secondary air injection, will result in

an increase of $26 in PGM costs. This is a third of what EPA has estimated for an I-4and will imply a ~32% increase in PGM loading. The second 2.0 L PFI vehicle, withoutsecondary air injection, requires additional ~$11 in PGM costs, implying a ~16% extraPGM loading in total. Total catalyst size increased between 40% and 200%. This wouldhave a small additional impact on substrate, washcoat and canning costs, of about $4 to$20. It was determined that the placement of PGM and advanced catalyst technologiesare critical for low cost emission solutions.

PGM nano-catalyst technology can reduce the precious metal loading by 90%, whileimproving thermal aging resistance, as demonstrated by Mazda researchers.6 In a

conventional TWC, the PGM is deposited on the surface of the support material; particlesintering (agglomeration into larger particles) occurs with thermal aging, resulting inthermal deterioration. The new developed catalyst contains nano-sized PGM particles

5Ball,D.andMoser,D.,"ColdStartCalibrationofCurrentPZEVVehiclesandtheImpactofLEV-

IIIEmissionRegulations,"SAETechnicalPaper2012-01-1245,2012,doi:10.4271/2012-01-

1245.6Iwakuni,H.,Miyoshi,S.,andTakami,A.,"DevelopmentofPGMSingleNanoCatalystTechnology,"SAETechnicalPaper2009-01-1079,2009,doi:10.4271/2009-01-1079.


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and specially designed washcoat materials. This development helps avoid thermalsintering after constant high temperature exposure (Figure 3). Tests on the Japanese10-15 mode show that the nano-PGM TWC performance was equivalent to thetraditional TWC, even with 1/10 of the original PGM loading. The size of the nanoparticle remained constant even after 300 hours of thermal aging (Figure 4). OSC

loading was increased with the new nano-PGM technology and washcoat. This newdesign was introduced in the Japanese market in MY2008.

Figure 3 Concept PGM single nano catalyst technology (SAE 2009-01-1079).

Figure 4 PGM Particle size after engine bench aging observed with TEM (SAE2009-01-1079)

In summary, the literature shows that improvements in technology have reduced PGMloadings and allowed more efficient TWCs. In fact, the literature suggests that ultralowPGM loading is possible, with adequate durability and sulfur tolerance, by improving theOSC formulation, washcoat layering and PGM zoning.

The trends of reducing PGM loading in parallel with more stringent standards suggestthat 30 mg/mile of NOMG+NOx can be achieved at very little extra PGM costs.


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Assuming that the PGM loading increases an average of 20%, which is the averagevalue found in Ball and Mosers work, the incremental costs of PGM loading shouldrange between $18 and $36 for Tier 3 vehicles, as presented in Table 3. This is about athird of the cost assumptions in the draft RIA. Note that these cost estimates are stillvery conservative, as other papers suggest that the PGM loadings for Tier 3 vehicles

can be reduced with respect to current Tier 2 Bin 5 PGM loading levels.

Table 3 Total and Incremental expected PGM costs per vehicle for 30 mg/mileNMOG+NOx

ITEMTIER 3 - PGM COST PER VEHICLE

30 MG/MILE NMOG+NOX

$/L I-4, 2.0L V-6, 3.0L V-8, 4.0L

Total costs $106 $159 $212

Incremental costs with respect to Tier 2 Bin 5 $18 $27 $36

Optimized CC Catalyst, Optimized Thermal Management, Secondary Air Injection,and Hydrocarbon Adsorber

Table 2-5 of the RIA lists substantial costs for Optimized CC Catalyst, OptimizedThermal Management, Secondary Air Injection, and Hydrocarbon Adsorbers. Whilethese cost estimates are not unreasonable, the EPA is greatly overstating the need forthese technologies and the Technology Application Rates in Table 2-11 of the draft RIAare far too high.

This is, in part, because EPA underestimates the benefits of fast catalyst light-offstrategies. These are discussed in section 1.4.1.2.1 of the draft RIA (page 1-23), but thediscussion does not quantify how much faster this technique can light off the catalyst. Inpractice, ignition retard and higher air flow rates are already being used on someproduction vehicles to light off the catalyst during the initial 20 second idle period. Thisreduces, if not eliminates, the need for optimized close-coupled catalysts, improvedthermal management, secondary air injection, and hydrocarbon adsorbers. Given theleadtime allowed by the proposed Tier 3 rule, this strategy can be effectivelyimplemented in all vehicles and will dramatically reduce the need for other measures toreduce catalyst lightoff times.

Another factor is that thermal management in exhaust systems is already widespread. Ifadditional thermal management is needed, as noted by EPA in their draft RIA,integration of the exhaust manifold into the cylinder head is an effective way to furtherreduce catalyst light-off times. Not only does this allow the catalyst to be mounteddirectly to the cylinder head for faster warmup, it is also a cost reduction.


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Variable valve timing (VVT) reduces NOx emissions during hot, running operation andimproves idle stability, allowing more aggressive idle retard strategies to help light offthe catalyst. As VVT has already been adopted on most engines due to its efficiencybenefits, these emission control improvements are virtually free.

Another factor is that sulfur affects the efficiency, not just of future Tier 3 vehicles, but ofexisting Tier 2 vehicles as well. Thus, removing sulfur will allow current catalyst systemsto operate more efficiently, even before considering catalyst improvements.

Warmed-up NOx catalyst conversion efficiency is strongly affected by air/fuel ratiocontrol. HC and CO oxidation can be maintained during brief rich excursions usingoxygen stored on the catalyst substrate. No similar mechanism exists for NOx reductionduring lean excursions. Every lean excursion - no matter how small or how brief -negatively impacts NOx reduction.7 Thus, the key to controlling warmed-up NOxreduction is absolute control of the air/fuel ratio at stoichiometric. The catalystimprovements discussed in section 1.4.1.3 of the draft RIA (page 1-28) are relativelyunimportant. Drive-by-wire systems are a key element of precise air/fuel control; theother requirements are mainly better software algorithms. As drive-by-wire systemshave already been widely adopted for drivability and efficiency reasons, the cost ofreducing warmed-up NOx emissions is very low.

The draft RIA states (page 1-24):It is anticipated that to meet the proposed Tier 3 SFTP standards, manufacturerswill need to ensure that fuel enrichment is not required on the US06 portion of theFTP.

This statement is not accurate. The impacts of fuel enrichment on engine out HC and

NOx and on HC and NOx catalyst conversion efficiency are relatively modest.8

Richoperation results in large increases in engine-out CO emissions, but engine-out HCemissions increase only modestly and NOx emissions decrease. In fact, engine-out COconcentrations are an excellent way to calculate air/fuel ratio. Rich operation alsodegrades HC and NOx conversion efficiency, but again the degradation is modest. It isCO conversion efficiency that plummets during rich operation. HC is oxidizedpreferentially to CO and oxygen storage on the substrate and the reduction of NOxprovides enough oxygen to maintain surprisingly high levels of HC oxidation with richair/fuel ratios for several seconds. Thus, as long as the SFTP CO standards are notreduced, manufacturers will be able to use limited amounts of enrichment during theUS06 cycle without significantly impacting their ability to comply with the SFTP

standards.

7 John German, "Observations Concerning Current Motor Vehicle Emissions", SAE 950812,Feb. 1995.8 Ibid.


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Finally, EPA also appears to be placing too much emphasis on early LEVII-SULEVvehicles, some of which used secondary air injection or HC adsorbers to ensurecompliance. These were the first vehicles to comply with lower emission standards andthey were relatively low volume. Due to the short development time and low productionvolume, in some cases it was easier and cheaper for manufacturers to add existing

hardware than to invest the engineering resources to fully optimize precise air/fuelcontrol and fast light-off strategies, or to develop new hardware. It is also important tonote that many manufacturers were able to meet the LEVII-SULEV standards withoutsuch additional hardware, even on their first attempt.

As manufacturers move towards compliance of all vehicles with the proposed Tier 3standards, the order of magnitude higher sales will create a major incentive formanufacturers to find cheaper solutions. There is also a considerable amount ofadditional leadtime, allowing manufacturers to devote substantial engineering resourcesand build upon their early experience with meeting low emission standards. It will not bedifficult for manufacturers to develop and implement emission control systems that donot require these expensive add-on security blankets.

In summary, while EPA's cost estimates for Optimized CC Catalyst, Optimized ThermalManagement, Secondary Air Injection, and Hydrocarbon Adsorbers are reasonable,these technologies will either not be needed or alternative technologies that are lowercost than those estimated by EPA will be used, if not an actual cost reduction. Inaddition, the cost for increased precious metal loadings will only be about a third of thecosts estimated in the draft RIA.

2) Gasoline Sulfur Reduction CostThe cost of reducing gasoline sulfur from 30 ppm to 10 ppm is very modest. The ICCTcontracted with MathPro in 2011 to evaluate the cost of reducing sulfur from 30 to 10ppm. MathPro found that the cost would be 0.8 to 1.4 cents per gallon. The costestimates include revamping the FCC naphtha hydrotreaters, historical rates of returnon investment, supplying the additional hydrogen needed, replacing small losses in bothgasoline volume and octane, and expanding sulfur recovery.

In fact, these cost estimates are likely overstated, as MathPro assumed that all existingFCC naphtha hydrotreating capacity would require revamping even though many

hydrotreaters installed to meet the Tier 2 sulfur requirements are already capable ofmeeting the 10 ppm standard.

A separate study carried out by Baker and OBrien for the American Petroleum institute(API) estimated that production of 10 ppm sulfur gasoline would increase the marginalrefining cost by 69 cents/gallon. However, there are two main reasons why thesemarginal cost estimates in the API study are unrealistic and should not be used.


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First, in the Baker and OBrien methodology, the indicated marginal cost is the highestcost of sulfur control that would be incurred by the least efficient refinery or refineries inthe US. The petroleum market in the US is regional, i.e., there is not a single market. Itis possible that the least efficient and highest cost refinery may be in, for example,PADD 4 and have a particular market to itself. That refinery might be able to pass the

marginal costs on to producers in that market but will not have any effects in the rest ofthe US. However, this is not the typical case, as most refineries are not so isolated. Highcost refineries that are not isolated will not be able to pass the marginal costs ontoconsumers, due to competition from other efficient refineries. As a result, it is theaverage costs, not the marginal costs that represent the actual increase in the refiningcost.

Second, the API marginal costs are upwardly biased. Baker and OBrien overestimatedthe investment costs for FCC naphtha hydrotreating, as indicated by MathPro's informalcontacts with companies involved in refinery upgrading. Their survey showed thatinvestment costs used by MathPro are in a reasonable range.

If the average refining costs are considered instead of marginal costs and Baker andOBriens investment costs for FCC naphtha hydrotreating are properly adjusted, Bakerand O-Brien's estimated refining costs would be similar to those estimated by MathPro.

There are two additional very important points. First, reducing gasoline sulfur will resultin large emission reductions not just from future Tier 3 vehicles, but also from the entirein-use fleet. The impacts of sulfur on older vehicles, in grams/mile, are fully as large ason Tier 3 vehicles, if not larger. As most of the sulfur impacts on catalysts are reversible,reducing gasoline sulfur will result in immediate and very large reductions of in-useemissions.

Second, analyses of catalyst precious-metal loadings and cost are generally donewithout considering changes in fuel sulfur. Reducing gasoline sulfur will enablereductions in catalyst precious-metal loadings, further reducing the cost of complianceand offsetting much of the cost of reducing fuel sulfur.

3) SFTP Standards

For the most part, the overall stringency of the proposed rules is adequate and the

provisions, including leadtime and credit provisions, are appropriate. However, ICCT isextremely concerned that the SFTP requirements are far less stringent than the FTPrequirements. While the proposed Tier 3 SFTP standards are a major improvement overthe SFTP standards for Tier 2, the Tier 2 SFTP standards were unchanged in stringencyfrom the Tier 1 SFTP standards and, thus, completely ineffective. Thus, despite thelarge reduction in the SFTP standard levels, the proposed SFTP standards are still fartoo lenient and will not achieve the objectives of the SFTP standards to reduce in-useemissions.


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To demonstrate our concerns, we have analyzed the stringency of the proposed SFTPstandards in two different ways. The first method compares the proposed SFTPstandards against current SFTP emission levels. The second method compares theproposed SFTP standards against the proposed FTP standards.

Current SFTP emission levels

Figure 1-5 in the draft RIA (page 1-18), reproduced below, demonstrates that theaverage SFTP NMHC+NOx emissions for currentvehicles certified to Tier 2 bin 2 orLEVII-SULEV emission standards (the orange bars) is less than 10 mg/mi, and thehighest emissions seen is about 42.5 mg/mi. The proposed SFTP NMHC+NOx standarddrops from 103 mg/mi in 2017 to 50 mg/mi in 2025. So, the proposed standard for 2017is more than 10 times the average emissions of current vehicles and the proposed 2025standard is more than 5 times the average emissions of current vehicles.

Proposed SFTP versus proposed FTP standards

The original SFTP standards, adopted in 1996 and applied to Tier 1 vehicles, found thatthe incremental emissions on the SC03 and US06 cycles was similar in magnitude tothe incremental emissions from the cold start on the FTP. Thus, SFTP standards forTier 1 vehicles were set at the same numeric level as the FTP standards.

As the SFTP standards are hot, running emissions only, it is appropriate to separate theFTP requirements into cold start emissions and hot, running emissions. The proposed


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NMHC+NOx FTP standards are 30 mg/mile. The draft RIA states (page 1-6):"Based on modal analysis of a gasoline powered vehicle being operated on theFTP cycle, approximately 90 percent of the NMOG emissions occur during thefirst 50 seconds after a cold start. In addition, about 60 percent of the NOXemissions occur in these early seconds."

The Tier 2 bin 2 standards were 10 mg/mi for NMHC and 20 mg/mi for NOx. Using thisratio and applying it to the cold start emission ratios from the draft RIA, 70% ofNMHC+NOx emissions on the FTP are from the cold start (90% x 1/3 + 60% x 2/3). Thismeans that about 30% of NMHC+NOx FTP emissions are from hot, running operationand, thus, account for about 9 mg/mi of the proposed FTP standards.

The proposed NMHC+NOx SFTP standards are 50 mg/mi, or 5.5 times higher than thehot, running emissions portion of the FTP standards. This is so lenient as to beessentially no off-cycle control. And this is with respect to current vehicles, much less for2025 with several additional generations of emission control development.

Similarly, compared with the proposed FTP PM standards, the proposed SFTP PMstandards are 3.3 times higher for vehicles < 6,000 GVWR and 6.7 times higher forvehicles > 6,000 GVWR. Again, this is so lenient as to be almost completely ineffective.

Discussion

After application of the standard 50 percent compliance margin, hot, runningNMHC+NOx emissions on the FTP are about 4.5 mg/mi. Current SFTP NMHC+NOxemissions from Tier 2 bin 2 and LEVII-SULEV vehicles are a bit less than twice this

amount. This is a reasonable ratio between SFTP and hot, running FTP emissions.This, in turn, indicates that the hot, running FTP comparison supports the analysis ofSFTP emissions from current vehicles.

Both the current SFTP data and the proposed hot, running emissions on the FTPsupport actual SFTP NMHC+NOx emissions of less than 10 mg/mi. After adding thestandard x2 in-use compliance margin, the SFTP NMHC+NOx standard should be setat no more than 20 mg/mi.

As cold starts have a relatively small impact on particulate emissions, the same timestwo factor found for SFTP NMHC+NOx emissions should also be applied to particulate

emissions. This means that the SFTP PM standard should be set at no more than 6mg/mi.

Further, there is no reason why light-duty vehicles over 6,000 GVWR should be held toless stringent particulate standards. This violates the premise established with the Tier 2emission standards that all light-duty vehicles should be held to the same emissionstandards. It is especially important that GVWR not be used to discriminate between


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different standards, as GVWR is easily gamed.

Setting appropriate SFTP standards is especially important for diesel vehicles. The coldstart in the FTP largely determines the emission control system design for gasolinevehicles. The primary need for SFTP gasoline engine standards is to ensure that proper

calibrations are used off-cycle and that emissions remain reasonable in-use. However,for diesel engines, the emission control system design is largely determined by highload operation. Thus, while the proposed SFTP requirements would likely not impactgasoline hardware design, ineffective SFTP standards could lead to selection of dieselemission control systems that are less effective in-use.

In fact, this has already been seen in Europe, where Euro IV and Euro V heavy-dutyvehicles equipped with selective catalytic reduction (SCR) systems have significantlyelevated emissions of nitrogen oxides (NOx) during in-use driving, particularly whenoperating in urban traffic. In some cases, actual in-use urban emission levels may be ashigh as or higher than those from much older vehicles with engines certified to morelenient emission standards.9 This illustrates the importance of setting emissionstandards using representative test procedures and appropriate standards.

4) Certification Test Fuel

The ICCT is concerned about the proposed revision to use E15 for the certification testfuel. While the ICCT supports using a more representative fuel for certification testing,E15 is not representative of in-use fuel. E10 is representative of current in-use fuels andshould be used for emission and fuel economy testing.

In addition to violating the principle of using representative fuels, the ICCT has anumber of serious concerns with E15: E15 can cause damage if it is used in smallengines or in legacy vehicles; it is specific to ethanol (as opposed to drop-in biofuelpathways), which encourages the use of food feedstocks such as maize instead of moreenvironmentally friendly feedstocks; and it provides significant evaporative cooling,which manufacturers could exploit to generate higher fuel economy on the tests than thevehicles would actually experience in use.

The problems and potential damage if E15 is used in small engines and legacy vehicleshas been well documented by Honda and other vehicle manufacturers and will not be

repeated here. However, our concerns in this area are exacerbated by the lack ofsystems to provide proper fuel and prevent misfueling in-use. For example, EPA has notproposed a system to separate the use of E15 for newer vehicles and E10 for oldervehicles. A system where E15 is used for regular fuel and E10 for premium fuel wouldencourage misfueling of small engines and legacy vehicles, as customers choose E15

9Lowell,D.andKamakate,F.,"Urbanoff-cycleNOxemissionsfromEuroIV/Vtrucksandbuses",

April2012.http://theicct.org/urban-cycle-nox-emissions-euro-ivv-trucks-and-buses


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just because it is cheaper. If E10 is used for regular fuel and E15 is used for premiumfuel, this would discourage the use of E15 in vehicles that could safety use it and wouldmake it impossible for older vehicles requiring premium to be refueled properly. Thus,for the refueling system to work properly, it appears that service stations must provideseparate pumps for both E10 and E15 for both regular and premium. This is not likely to

happen unless EPA requires it. Until EPA addresses the refueling situation withregulations, refueling will almost certainly be marked by confusion and misfueling.

The ICCT is also concerned that E15 will encourage biofuels made from food crops,instead of advanced biofuels. It is not currently cost effective to make ethanol out ofcellulose, thus simply increasing the ethanol blend wall is effectively a mandate for morefood-based biofuels that can easily be turned into ethanol. Several pathways forproducing advanced biofuel from feedstocks such as cellulose will likely be able todeliver drop-in fuels. As drop-in fuels have a higher value in the market than ethanol, itis also possible that cellulose can be more profitably turned into drop-in fuels. E15would work against this by incentivizing ethanol, not drop-in fuels. Insofar as wider useof E15 supports increased use of maize and sugarcane ethanol rather than drivinginvestment into advanced drop-in fuel pathways, the net result will be that E15 wouldtend to increase food prices (and hence worldwide food insecurity), decreasebiodiversity due to land use change, create yet another roadblock for advanced, lowercarbon, biofuels and deliver less carbon reductions than would be available fromcommercializing biofuels from cellulosic wastes and energy crops.

The ICCT's third concern is specific to fuel economy testing. 15% ethanol contentprovides significant evaporative cooling in the cylinder. This would allow manufacturersto advance ignition timing or make other modifications to improve fuel economy on the

test cyclesand which would not be likely to be achieved in-use.

The advantages of even E10 were demonstrated in a test program to maximize enginepower on a variety of fuels. Grassroots Motorsports (December 2012) tested a MazdaMiata on the following fuels, using a standalone computer to tune the vehicle for eachfuel on a Dynapack dynamometer to make the most power:

Table 4: Results of Mazda Miata testing by Grassroots Motorsports

OCTANE ETHANOLPOWER

(HP)TORQUE(FT-LB)

87 E10 135 117

93 E10 136 124

93 0 134 122

100 0 137 123

105 0 137 124

-- E85 143 128

The charge cooling effect of E10 boosted performance on 93-octane fuel by about 1.5%


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and virtually matched the performance of 100 and 105-octane race gasoline. GRMcouldn't redesign the engine and they were only able to revise spark timing, camshafttiming, and air/fuel ratio at WOT. The higher charge cooling with E15 would allowmanufacturers to do even more optimizingand they could also optimize the design ofthe engine over all operation.

It is important that the fuel used for certification and fuel economy testing berepresentative of in-use fuel. However, that fuel is currently E10, which is what shouldbe used for EPA's testing. E15 is not currently representative of in-use fuel and its usefor EPA testing has several major problems, which should be avoided.

5) Provisions for E30 Vehicles

The draft proposal requested comments on the use of E30 in certification testing:

"we are proposing to allow vehicle manufacturers to request approval for analternative certification fuel such as a high-octane 30 percent ethanol by volume(E30) blend for vehicles they might design or optimize for use on such a fuel."

The ICCT is supportive of all ways to increase efficiency. In particular, the ICCT wouldstrongly support increasing the minimum required octane for all gasoline.

Despite this, the ICCT could support the E30 provision only if the vehicles actually usedE30 the vast majority of the time in-use. However, this would create major infrastructuredifficulties: how would the E30 infrastructure be developed in advance of offering E30-

capable vehicles? It also has potentially troubling consequences related to food-basedhigh-iLUC ethanol, as discussed above with respect to E15.

An entirely new infrastructure would be needed for E30, which means a huge chicken-and-egg problem. Just like with E85, one way to attempt to solve this is to offer creditsto E30 vehicles, whether or not they actually use E30 in-use. The ICCT is extremelyconcerned that this will become another loophole, with large credits against theCO2/CAFE standards granted and little use in the real world, reducing the benefits of thestandards. Our concerns are magnified by the recent EPA Manufacturer GuidanceLetter on E85 usage, which proposed to grant flexible-fueled vehicles a 20% E85 usagerate (F-factor), even though E85 usage in the real world has remained steady at 1.1%

since 1998.

Our infrastructure concerns are exacerbated by the fact that E30 has 10% lower energycontent than gasoline. Certainly some of this can be recaptured with higher efficiency,but it won't be a 10% efficiency improvement. Thus, customers will be able to travelfurther on gasoline (or E10 or E15) than with E30, unless the vehicle is designed so thatit does not run well on E10 or E15.


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Which raises another concern with vehicles designed for E30. A recent SAE paper onthe impacts of ethanol blends reviewed what happens when a vehicle designed for E30is run on 87-octane gasoline:10

"With engine downsizing, the reduction in full load torque with regular grade 91

RON fuel will be proportional to the amount of downsizing, and can result inunacceptable vehicle performance attributes for aggressive levels of downsizing."

This loss of performance on regular fuel just makes the chicken-and-egg problemworse. Engines that require E30 are going to be a tough sell in the market.

Given the infrastructure concerns, E30 must offer substantial efficiency benefits to justifythe investment in a new infrastructure. Thus, the key question is: What is the efficiencybenefit of running on E30 compared to alternative technologies? The Stein 2013 SAEpaper concluded: "From an engine standpoint, the primary motivation for increasingethanol content is improved knock resistance."11 However, high EGR rates also offerimproved knock resistance. If E30 basically duplicates the benefits of boosted-EGR, it ishard to see how creation of a new infrastructure can be justified.

Given all of the above, E30 should only be allowed if the manufacturer can demonstratethat the vehicle will almost always be refueled with E30 in-use. Given the historicalabuse of similar provisions, such as FFV credits and the recent proposal for 20% F-factor for FFVs, the ICCT is very concerned about the potential to also abuse thisprovision.

What is really needed is higher octane for regular fuel, regardless of the ethanol

content. For example, the Mazda had to reduce the compression ratio of the Skyactivengine for the US market, compared with Europe. Also OEMs simply won't try to sell amass-market non-luxury vehicle that requires mid- or high-grade gasoline in the US.

Unfortunately, when fuel providers added ethanol to gasoline in the past, the fuelproviders took out the non-ethanol octane elements - so that, in practice, there hasnever been a gain in octane through increased ethanol blends. It is likely that E15 willbe the samewe won't actually get more octane. Rather than focus on ethanolrequirements, the EPA should raise the minimum octane requirements for all gasoline.

10Stein,R.,Anderson,J.,andWallington,T.,"AnOverviewoftheEffectsofEthanol-GasolineBlends

onSIEnginePerformance,FuelEfficiency,andEmissions," SAEInt.J.Engines6(1):470-487,2013,

doi:10.4271/2013-01-163511

Ibid.


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6) Heavy-Duty Standards

It is ICCT's position that technology-neutral performance standards are critical in anytransportation policy, especially one that involves multiple and alternative fuels that canall be utilized as part of meeting emissions and energy objectives. Thus, we are

supportive of maintaining fuel neutral criteria emissions standards for heavy-dutyvehicles.

The ICCT fully supports extending chassis-based emission requirements to all completevehicles up to 14,000 gross vehicle weight. The trend since the first standards wereadopted in the 1970s has been to increase the GVW of pickup and other light trucksabove the threshold for light-duty emission standards. This has especially been aproblem for diesel engines in pickup trucks, which are only sold above 8,500 GVW inorder to avoid the light-duty emission standards. Extending the threshold to 14,000GVW will ensure emission standards are applied appropriately to all complete vehicles.

Similarly, the ICCT fully supports extending the supplemental FTP requirements tocomplete vehicles between 8,500 and 14,000, which were previously exempt.

As noted by EPA, companies with much larger sales of light-duty trucks build most ofthese vehicles and frequently share major design characteristics and potentialemissions control technologies with their LDT counterparts. Combined with the less-stringent standards proposed by EPA (as compared to light-duty vehicles), compliancewith the proposed heavy-duty standards should be feasible at reasonable cost.

7) R-Factor for Carbon Balance EquationThe R-factor is an adjustment made by EPA to maintain compatibility with the testprocedures used in 1975 for calculating fuel economy, as required by the 1975 EPCA.The R-factor is used to adjust the FE test results for changes in the net heating value(NHV) of the test fuel. EPA is accomplishing this by incorporating the R-factor into thecarbon balance equation, instead of doing the adjustment after calculation of the fueleconomy.

Specifically, the R-factor is the sensitivity of the fuel economy to changes in NHV.Ethanol blends reduce the NHV of the test fuel. To the extent that NHV affects engine

efficiency, this change must be accounted for under the 1975 EPCA.

Current, an R-factor of 0.6 is in the regulations. This was based upon data submitted byGM and others in 1985 on primarily carbureted vehicles. In the past there was not a lotof variation in fuel properties of indolence, so this R-factor had a minor effect and therewas no need to revisit it.


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However, switching to E10 as the test fuel will cause a much larger change in the NHV -about 3.5% for E10 (and over 5% for E15). Using an R-factor of 0.6 would give anartificial upward adjustment of over 2% (0.4 x 5%) to E15 vehicles.

ICCT commends EPA for having the foresight to readdress the R-factor. A contractor

report for EPA by ORNL, based upon test data on recent vehicles using E0, E10, E15,and E20, calculated R-factors for the entire fleet, Tier 2 vehicles only, and with andwithout exclusion of an outlier vehicle.12

The existing R-factor is clearly outdated and needs to be replaced. Vehicles certified toTier 2 are representative of current vehicles and are the closest representation of futureTier 3 vehicles, so data from older non-Tier 2 vehicles should not be used. The HondaAccord data is clearly an outlier and is likely the result of an error in testing. It isstandard practice in statistics to exclude such obvious outliers. Thus, the ICCTrecommends that the R-factor found in the report for Tier 2 vehicles without the outlier,0.96, be adopted in the final rule.

8) Refueling Emissions of Natural Gas Vehicles

The impact of refueling emissions on all alternative fuel vehicles, especially gaseous-fueled vehicles, should be assessed. A key concern for natural gas vehicles, inparticular, is the atmospheric venting of natural gas that occurs during refueling. Naturalgas not only contains criteria hydrocarbon pollutants, it also contains a large percentageof methane with a 100-year global warming potential 25 times that of CO2. It is veryimportant that this venting of natural gas be controlled and recaptured.

The ICCT recommends that EPA develop and adopt requirements for refuelingemissions from gaseous-fueled vehicles.

9) FTP Particulate Emission Standards

The FTP supports the proposed FTP particulate standards. These would largelyharmonize EPA's requirements with CARB's.

One key difference between the Tier 3 proposal and the LEV III rule is that under LEV

III, automakers must meet a tailpipe emission standard of 1 mg/mi beginning in 2025.Instead, the Tier 3 proposal extends only to model year 2023, citing concerns expressedin the CA LEV III rulemaking with regard to the state of PM measurement capability toenable testing and compliance with a 1 mg/mi standard.. The ICCT strongly

12Sluder, C. and West, B., "PreliminaryExaminationofEthanolFuelEffectsonEPAsR-factorfor

VehicleFuelEconomy",ORNLreportforEPA,June2013


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recommends that EPA harmonize with the LEV III particulate standards beginning in2025. This will allow plenty of time to develop more accurate particulate measurementmethods.

A notable omission from the proposed particulate standards is a particle number limit

standard, similar to already adopted requirements in Europe. Although the proposalcites the 2010 US EPA Integrated Risk Assessment for Particulate Matter, whichhighlights evidence of a causal association between PN exposure and adverse healthimpacts, the document notes a desire for further research to find more robustassociations between PN exposure and health impacts. The ICCT strongly encouragesEPA to investigate harmonization with the European particulate number standards in thefuture. California is likely to pursue particle number measurement methods to ensurecompliance with 1 mg/mi, which carries the possibility of a transition to a particlenumber limit in future rulemakings.

Comments on Tier 3 LDV NPRM

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