Reducing GHGs in Transportation: On the Road to Less Carbon 2013 ERC Symposium Madison, Wisconsin June 5, 2013 Matthew Brusstar U. S. Environmental Protection Agency National Vehicle & Fuel Emissions Laboratory
Overview Regulatory outlook for Light-Duty and Heavy-Duty GHGs Criteria emissions Near-term implications to light-duty engines Technology trends and projections EPA s light-duty engine test program Benchmarking activities Technology development areas Role of alternative fuels in heavy-duty engines GHG reductions Alternatives vs. renewables EPA work with RCCI in heavy-duty engines Combustion development On-road demonstration Summary Reducing GHGs in the context of lower criteria emissions 2
Regulatory Outlook EPA Light-Duty Regulations EPA/NHTSA GHG National Program (MY 2017-2025) Together with Phase 1 (MY 2012-2016), reduces GHG emissions by half (2X fuel economy) compared to MY 2010 Tier 3 Vehicle Emissions Program (proposed) Phased-in reductions of tailpipe emissions for cars and trucks: 30 mg/mile combined NOx+NMOG 3 mg/mile PM Reduction in gasoline sulfur content to 10 ppm starting in 2017 Heavy Duty Regulations EPA/NHTSA Phase 1 GHG Program (starting MY2014) NHTSA regulates fuel consumption. EPA regulates CO2, N2O, CH4 and HFCs. EPA/NHTSA Phase 2 GHG Program (as proposed in Phase 1) Agency is in an information gathering stage Compliance model development (GEM) Test procedure development California criteria emissions standards ( 2050 vision targets) 80% NOx reduction from HD trucks starting in 2023 (ARB Workshop, 8/21/12) 3
Light-Duty GHG Standards and Actual Fleet Emissions GHG standards lead to a fleet average of 143 g/mi CO 2 for cars, 203 g/mi for trucks in 2025 Adjusted for real world factors gives around 40 mpg Industry is on course to meet the standards Technologies are being introduced today to enable compliance with 2025 Further technology development will be needed to continue the path to 2025 GHG Emission (g/mile) 700 600 500 400 300 200 100 0 Passenger Car Actual Passenger Car Standard Light Truck Actual Light Truck Standard - Historic GHG Emissions calculated from EPA Trends Report - No adjustments for emission credits 4
Technologies Adopted to Meet Future CO 2 Standards (assumes improvements in A/C systems) 100 90 Number of Models 80 70 60 50 40 30 20 10 CNG EV Fuel Cell PHEV HEV Diesel Gasoline 0 2016 2017 2020 2025 Source: EPA Report 420-R-13-001 5
(Fleet Projections) 6
(Fleet Projections) 7
Light-Duty Rulemaking Context (present-2025) Tier III Fuel Sulfur 10 ppm (proposed for 2017) 2017-2025 Tier 3 Emissions (proposed) 2008-2022 Renewable Fuel Standard 2012-2025 Phase I & II GHG Rules
Shifting Paradigms in Light-Duty Transportation Heavy Oil Imports Few alternatives No renewables Modest Oil Imports Some alternatives Few renewables Low Oil Imports? Many alternatives? Abundant renewables? Tier III Fuel Sulfur 10 ppm (proposed for 2017) Lower 0-60 times Larger (more trucks) Heavier Smaller (fewer trucks) More technologies New technologies 2017-2025 Tier 3 Emissions (proposed) 2008-2022 Renewable Fuel Standard 2012-2025 Phase I & II GHG Rules More hybrids? Dedicated alt fuels? Vastly lighter? Autonomous control? Mode changes?
NVFEL Light-Duty Engine Programs LD GHG Test Program Goals: Conducting feasibility assessments of key emerging powertrain technologies (engines, transmissions, hybrids) Expanding our understanding of subjective factors (e.g., NVH, driveability, etc.) Collecting data for vehicle simulation models (ALPHA) Sharing test results with industry and the public Approach: Benchmarking and near-term technology development, in the following areas: Boosted, downsized GDI engines High-compression ratio naturally-aspirated GDI engines Diesels and Lean Burn Gasoline engines 10
Engine Benchmarking Activities Engine Test Article (on engine dyno) Vehicle/ECU (static) Engine Harness to ECU (on board vehicle)
Steady State Efficiency Mapping Torque Curve/Test Points BSFC Map (Preliminary)
Open ECU Development Step 1: Vehicle evaluation on chassis dyno Emissions measurement, OBD monitoring FTP, HWFET, US06, steady-state Step 2: Engine benchmarking using Stock ECU Repeat vehicle tests using simulated engine cycles Engine fully instrumented CAN bus data recorded Engine data is fed into tables and models used to develop the open-ecu calibration Step 3: Repeat engine benchmarking using Open ECU, with same calibration as Stock ECU Repeat engine cycles Step4: Engine hardware development supported by Open ECU
EPA s GDI Engine Test Program Spray-guided Cold Start (Tier 3) Dilute (EGR) Single-cyl (GREEN) Lean Burn, HCCI Stoich, Tier 3 (Multicyl) Multi-cylinder (BLUE) Baseline Dilute (Multicyl) Wall-guided Stoich, Tier 3 (Multicyl) Multi-cylinder (RED) Baseline High CR, Atkinson 2013 2014 2015 2016 14
GHG Emissions in the MD/HD Sector 3% 3% 2% Transportation Related Greenhouse Gas Emissions (Tg CO2eq) in 2010 8% Light-Duty Vehicles Heavy-Duty Trucks and Buses Aircraft 23% 62% Ships and Boats Rail Other (Motorcycles, Pipelines, Lubricants) Source: U.S. Greenhouse Gas Emissions and Sinks 1990-2010 (EPA 2012) 15
Alternative Fuel Prices: CNG Regional variation in retail fuel prices (April 2013) Diesel Gallon Equivalent (DGE) basis West Coast CNG=$2.74 Diesel =$4.19 Rocky Mountain CNG=$1.81 Diesel =$3.91 National Average CNG=$2.34 Diesel=$3.99 Midwest CNG=$2.07 Diesel =$3.95 New England CNG=$2.87 Diesel=$4.16 Central Atlantic CNG=$2.42 Diesel =$3.97 Source: April 2013 DOE Clean Cities Alternative Fuel Price Report Gulf Coast CNG=$2.36 Diesel =$3.86 Lower Atlantic CNG=$2.22 Diesel =$3.90 16
Alternative Fuel Prices: E85 Regional variation in retail fuel prices (April 2013) $/gallon West Coast E85=$3.53 Diesel =$4.19 Rocky Mountain E85=$3.20 Diesel =$3.91 National Average E85=$3.30 Diesel=$3.99 Midwest E85=$3.21 Diesel =$3.95 New England E85=$3.54 Diesel=$4.16 Central Atlantic E85=$3.42 Diesel =$3.97 Source: April 2013 DOE Clean Cities Alternative Fuel Price Report Gulf Coast E85=$3.13 Diesel =$3.86 Lower Atlantic E85=$3.40 Diesel =$3.90 17
18 Domestic Fuel Pathways Feedstocks Petroleum Conventional Unconventional Tight shale oil Natural Gas Conventional Shale Gas Biomass Woody Herbaceous Corn/sugar Fats/oils Wind/solar/renewables Coal Oil shale (kerogen) Fuels Gasoline Conventional MTG Diesel Conventional Fischer-Tropsch Biodiesel Ethanol Methanol CNG / LNG Electricity Hydrogen Prime Movers Conv. CI/SI Flex-fuel Dedicated fuel Dual-Fuel Alcohol CNG EV/PHEV Fuel cell
Dual Fuel (Diesel/Alcohol) Test Program Outgrowth of three earlier low-temperature combustion activities: Clean-diesel (0.2 g/bhp-hr engine-out NOx) Gasoline HCCI/RCCI Dedicated alcohol SI combustion Use of alcohol opens a range of technical options: Fuels: ethanol (E85) or methanol (M100) NOx aftertreatment: EGR (0.2 g/bhp-hr) or SCR (<0.2 g/bhp-hr) Thermochemical waste heat recovery Engine and vehicle demonstration
Research Engine Description Feature Dual Fuel (Diesel/Alcohol) Base Engine Test Platform Navistar/MWM 4.8L Configuration 4 cyl, inline Displacement 4.8 liters Bore x Stroke 105mm x 137mm Compression Ratio 16.8:1 Max. power 143 kw @ 2200 rpm Valvetrain 4 valve/cyl, overhead valve Fuel Injectors PFI (2/cyl); HPCR/1800 bar Fuel Type M100/Diesel Ignition System (None) Air Induction System VGT Engine Control Module Pre-production controller Exhaust Aftertreatment DOC/DPF 20
Dual-Fuel (RCCI) Engine: Results Diesel-Methanol (M100) Calibrated to 0.27 g/kwh NOx Brake Efficiency (%) 40% Particulate Emissions (FSN).02 to.08 Results from EPA s initial calibration of a 4.8 liter dual-fuel engine 21
Dual-Fuel (RCCI) Engine: Results Diesel-Methanol (M100) M100 Substitution Ratio (mass basis) 91% >90% peak substitution by mass (80% by energy) Fuel substitution limited by combustion stability at lighter load Improvements seen through modified injection strategy Results from EPA s initial calibration of a 4.8 liter dual-fuel engine 22
Dual-Fuel Class 6 Vehicle Demonstration Results of Initial Field Tests Class 6 UPS truck evaluation Fall/Winter 2012/13 Initial results (circled in red) of EPA s proof-of-concept 4.8 liter dual-fuel engine installed in a class 6 UPS package car running on diesel and methanol (as the alcohol fuel). Diesel substitution expected to increase with recent injection strategy improvements Potential usage of up to 60-65% methanol DGE and 35-40% diesel for on-highway usage test date weight Route Diesel * (gals) diesel fuel (%) DF diesel cost ($) Methanol * (gals) Methanol (DGE) Methanol fuel (%) Methanol cost ($) Total Distance (miles) Nov 28 & 29 10600 City 24.20 69.4% $96.80 23.98 10.66 30.6% $31.97 460 Dec 3&3 10600 Highway 9.00 50.1% $36.00 20.16 8.96 49.9% $26.88 247 Dec 4 & 6 16600 Highway 15.00 49.9% $60.00 33.90 15.07 50.1% $45.20 316 23
BTE Sensitivity to EGR Levels
Next-Step Improvements Address NOx aftertreatment tradeoffs Potential for ultra-low NOx emissions (<<0.2 g/bhp-hr) Improve cold temperature operation Improve cold start, warmup transition Avoid late Start of Combustion at inlet air temperatures below 20 F (January in Ann Arbor) Optimize fuel injection strategy Maximize fuel substitution ratio Optimize engine-out emissions, aftertreatment Build confidence in durability Lack of lubricity in FIE, valve seats, cylinder liners Oil dilution So far, so good
Summary: Reducing GHGs, Criteria Emissions Meeting concurrent GHG and criteria pollutant standards pose a different set of challenges ahead: Light-duty: Cold start, PM: spray-guided vs. wall-guided DI systems US06 PM limits: cooled EGR vs. enrichment CA LEVIII PM standards (1 mg/mi after 2025): Injection pressure vs. GPF ULSG: New opportunities for lean burn? Heavy-duty engines: Ultra-low NOx (California) What is the future of Low-Temperature Combustion (LTC)? EGR vs. lean-nox aftertreatment efficiency Alternative/renewable fuels Is the heavy-duty sector the best use of alcohol fuels?