Biodiesel Utilization Ann Brennan, Manager Technology Integration Group Center for Transportation Technologies & Systems Mobilizing NC Conference April 18, 2007

2 What is NREL? National Renewable Energy Laboratory, Golden, CO  Nation’s premier laboratory dedicated to renewable energy and energy efficiency R&D  Established by U.S. Department of Energy in 1977  Programs span basic science to technology implementation; solar, wind, and buildings to fuels and vehicles  Center for Transportation Technologies and Systems  Advanced Vehicle Systems: hybrids and PHEVs, auxiliary loads, energy storage, tires  Fuels Performance: renewable and advanced fuels research and testing, ReFUEL vehicle lab  Technology Evaluation & Integration: fleet evaluation; data and information; support to fleets, Clean Cities, Alternative Fuels Data Center

3 What is biodiesel? Mono-alkyl esters of fatty acids (i.e., methyl or ethyl esters) Mostly made from soybean oil; also other oils, waste fats & grease Made in chemical reaction that combines oil, alcohol, and catalyst Must meet the quality requirements of ASTM D6751 Typically used as blend with petrodiesel (up to 20%) $1/gal tax credit for agri-biodiesel (vegetable oil/animal fat), $0.50/gal for waste cooking oil – initiated in January 2005

4 What is NOT biodiesel? Biodiesel is NOT unrefined vegetable oil or used cooking oil The much higher boiling point and viscosity of straight vegetable oil leads to engine carbon deposits, reducing engine life or increasing maintenance costs Fact sheet can be found here

5 How is Biodiesel being used in US? As a blending stock with petrodiesel (B20)  Federal, state, and alternative fuel provider fleets  EPAct and Executive Order Compliance  Other public and private fleets In low levels with petrodiesel (B2)  Lubricity and Ultra Low Sulfur Diesel Fuel  Agriculture supporting its own product Very limited B100 Use

6 Biodiesel Production National Biodiesel Board estimates 250 million gallons for 2006 Current production capacity is more than 500 million annual gallons More than 500 million annual gallons under construction or planned

7 Biodiesel Blenders Tax Credit American Jobs Creation Act ¢ per percentage of biodiesel blended  Vegetable oils and animal fats  B20 = 20 ¢, B2 = 2 ¢ 1/2 ¢ for recycled oils Must meet ASTM D6751 Highway Trust Fund is not impacted Effective January 1, 2005 Expires December 31, 2008 (extended in 2005 Energy Policy Act)

8 Biodiesel Operational Issues (≤ B20) Fuel Properties  High cetane, ultra-low sulfur, high lubricity, poor cold flow Fuel quality and proper storage are critical  Compliance with ASTM D6751 No engine modification required Slightly reduced fuel economy  B100 is ~10% lower energy content per gallon than diesel Potential for reduced oil drain interval based on lower particulate matter emissions Warranty coverage varies by manufacturer

9 Emission Benefits of B20 Broad agreement on emission reductions:  10% to 25% reduction in PM, depending on engine, test cycle, and other factors  10% to 20% reductions in CO, HC, and toxic compounds Several studies confirm life-cycle CO 2 emission reductions ~16% for B20 Impact on NO x emissions is less certain

10 Biodiesel Effect on NO x NO x can go up or down depending on engine and cycle –This is not well understood quantitatively Compilations of available data that are not weighted to one engine model show no change in NO x on average for B20 Based on the data available today: –B20 appears to have no significant or consistent impact on NO x emissions

11 B20 results in substantial PM reduction even with DPF B20 Testing with Diesel Particulate Filter Williams, et al., “Effect of Biodiesel Blends on Diesel Particulate Filter Performance” SAE Reduction with DPF ranges from 20% to 70%, depending on basefuel, test cycle, and other factors Reduction in sulfate emissions Increased PM reactivity caused by biodiesel

12 Biodiesel Fleet Evaluations Compares B20 to diesel control group  Identical engines, similar routes  Data collected on fuel use, mileage, maintenance, emissions FleetLocationVehicle Denver RTDBoulder, COOrion V / Cummins ISM – 40’ transit bus St. Louis MetroSt. Louis, MOGillig / Cummins ISM – 40’ transit bus USPSMiami, FLMack model MR866P tractor and Ford 9-ton cargo van

13 RTD: Fuel Economy and Maintenance Study concluded in July month duration Over 100,000 miles per vehicle Slightly higher maintenance costs for B20 Not statistically significant Caused by one event near end of study Oil analysis indicates no harm in terms of ZDDP and TBN decay, oxidation, fuel dilution, or viscosity. Potential advantage in lower soot loading, lower wear metals.

14 USPS Fleet Results Mack engine & maintenance costs similar until Nov 03 injector replacement  Suspected cause is out-of-specification B20 fuel Differences not observed in Ford cargo vans  Differences in maintenance costs not attributed to biodiesel-related issues MackFord

15 NBB Fleet Evaluation Team A preliminary report, “Equipment Effects Of Using B20, a 20% Biodiesel Blended Fuel, As a Replacement for Diesel Fuel in the United States” Review of data from four fleet studies Findings  Filter plugging  Materials compatibility  Fleets “satisfied” with B20 use Technical Recommendations  Ensure biodiesel meets ASTM specs  Ensure homogenous product  Avoid long-term storage  Be aware of cold weather properties

16 Closing Remarks Biodiesel is a significant sustainable energy resource for the United States Use of high quality biodiesel meeting ASTM D6751 is critical for good performance Work is ongoing to develop ASTM specifications for biodiesel blends B20 produces robust reductions in emissions of soot, toxics, and carbon monoxide There are not sufficient data to say if B20 blends cause NO x, on average, to go up or down Quantitative fleet evaluation results show no significant difference in operating costs or engine wear for use of petrodiesel versus B20 –much more in-use data is required to fully understand B20 impacts Major research need is testing of biodiesel in post-2006 engines

17 Biodiesel Resources NREL Fuels Group: Biodiesel Publications DOE Alternative Fuels Data Center  Publications  Federal & state incentives  Handling & use guidelines  Station locations DOE Regulated Fleet Programs National Biodiesel Board