# Presentation: 416491

## BEST PRACTICES FOR GREENHOUSE GAS EMISSIONS REDUCTIONS IN FREIGHT TRANSPORTATION

**Department of Civil, Construction, and Environmental Engineering**
**North Carolina State University**
**Raleigh, NC  27695**
**Prepared for:**
**Talking Freight Seminar Series**
**Federal Highway Administration **
**January 17,  2007**

**BEST PRACTICES FOR GREENHOUSE GAS EMISSIONS REDUCTIONS IN FREIGHT TRANSPORTATION**

**H. Christopher Frey, Ph.D. and Po-Yao Kuo **

## Objectives

- Identify and characterize potential best practices for reduction of greenhouse gas (GHG) emissions from the freight transportation sector
- Assess and compare these best practices
- Develop a guidebook regarding these best practices

## Introduction

- Definition of Key Concepts
- Study Methodology
- List of Best Practices
- Total Modal GHG Emissions Reductions
- Comparisons of Best Practices Assessed Quantitatively
- Inter-modal Substitutions
- Overview of the Guidebook
- Conclusions and Recommendations

## GHG Emissions in U.S. Freight Transportation, 2003

**GHG Emissions in U.S. Freight Transportation, 2003**

- *U.S. Total includes Bunker fuel for international aviation and marine

- (9%)

- Billion Tons CO2 eq.

## Distribution of GHG Emissions by Mode within the U.S. Freight Sector, 2003

- Total GHG Emissions: 7.20×108 Tons CO2 Equivalent

- Rail
-  6%

- Water
-   13%

- Air
-  5%

- Pipeline
-    16%

- Truck
-   60%

## Definitions and Concepts

**Best Practices:**
- Technological or operational strategies
- Existing or developing strategies or technologies
- Reduce GHG emissions
- Reduce energy use or use of alternative fuels
- Reduce refrigerant leakage or increase use of low Global Warming Potential (GWP) refrigerants

## Definitions and Concepts

**Subgroup:**
- A collection of best practices in a mode that have either common goals or attributes
**Greenhouse Gas Emissions:**
- Focus on CO2, CH4, and HFCs
- Global Warming Potential (GWP):
- GWP =        1 	for CO2
- GWP =      21 	for CH4
- GWP = 1,300 	for HFC-134a
**Developmental Status:  **New concepts, pilot tests, and commercially available systems

## Study Methodology

| (1) | Identify best practices |
| --- | --- |
| (2) | Assess maximum reductions in 2025 GHG emissions and energy or refrigerant use |
| (3) | Assess cost savings |
| (4) | Summarize and report assessment results |

## Assessment of Potential GHG Emissions Reductions for Individual Best Practices

**Per-device reductions**:
- Differences in 2025 per-device emissions with vs. without the Best Practice (BP)
- For alternative fuels, life cycle inventories were assessed
- May apply only to a fraction of devices in a mode
**Modal reductions**:
- Differences in 2025 modal emissions with or without the BP
- Best estimate of market penetration by 2025

## Assessment of Potential GHG Emissions Reductions for Multiple Best Practices

- Aggregate reductions for a subgroup:
- Linear combination of individual best practices
- Mutual exclusion
- Some BPs cannot be used simultaneously
- Based on BP with the highest reduction potential
- Interaction:
- Some BPs can be used together but interact
- Quantification of interaction is unknown or not reported
- Used a linear combination as an estimate

## Qualitative and Quantitative Assessment of Best Practices

- Quantitative estimates of the reductions in GHG emissions, energy use and refrigerant use are made for all best practices
- Quantitative Assessment of Costs of Best Practices:
-    - Where sufficient cost data are available
-    - Summarized in standardized reporting tables
- Qualitative Assessment of Best Practices:
- 	- Lack of quantitative cost data
-    - Summarized in simplified summary tables

## Quantitative Assessment of Best Practices (Example: Auxiliary Power Units)

- A truck with sleeper cab is estimated to consume up to        0.85 gallons of diesel per hour while idling

- Source: Volvo Trucks North America, www.volvo.com/trucks/na/en-us/
- Auxiliary power units (APUs) are estimated to consume 0.2-0.4 gallons of diesel per hour

## Quantitative Assessment of Best Practices (Example: Auxiliary Power Units)

- Practice goals, 2025:
-    - Trucks with sleeper cabs
-    - Reduce CO2 by 15 million tons per year
-    - Reduce energy use by 185 Tera BTU per 	year
- Practice summary: Auxiliary power units (APU)
- 	- Small diesel engine-generator
- 	- Used instead of base engine for idling
- 	- Supply power for electrical air conditioning, 	heating, and auxiliary loads

## Quantitative Assessment of Best Practices (Example: Auxiliary Power Units)

| Variable | Unit | Value |
| --- | --- | --- |
| Annual ton-miles for the mode | 109 ton-miles/year | 2,098 |
| Annual ton-miles to which a practice is applicable | 109 ton-miles/year | 453 |
| Annual GHG emissions reduction | 106 ton CO2 eq./year | 15.0 |
| Annual energy use reduction | 1012 BTU/year | 185.0 |
| Unit GHG emissions reduction | 10-3 lb CO2 eq./ton-mile | 66 |
| Unit energy use reduction | BTU/ton-mile | 409 |

**Standardized Reporting Table**** for Expected Reductions, 2025**

## Quantitative Assessment of Best Practices (Example: Auxiliary Power Units)

| Variable | Unit | Value |
| --- | --- | --- |
| Capital cost | 106 USD ($) | 9,370 |
| Annual O & M cost | $ 106 /year | 520 |
| Annualized cost | $ 106 /year | 2,990 |
| Annual energy cost saving | $ 106 /year | 3,430 |
| Net savings | $ 106 /year | 440 |
| Net savings per unit of GHG emissions reductions* | $/ton CO2 eq. | 29 |
| Net savings per unit of energy use reduction* | $/106 BTU | 2.3 |
| Simple payback period | years | 3.2 |

- *Positive values denote cost savings

**Standardized Reporting Table**** for Expected Practice Costs and Cost Savings, 2025**

## Summary of Best Practices for Freight Transportation

*A total of 59 potential best practices have been identified*

| Mode | Number of  Potential Best Practices |
| --- | --- |
| Truck | 33 |
| Rail | 6 |
| Air | 10 |
| Water | 5 |
| Pipeline | 5 |

## List of 33 Best Practices for the Truck Mode

| Subgroup | Names of Best Practices | Note |
| --- | --- | --- |
| Anti-idling | Truck Stop Electrification (Off-board, on-board);* Auxiliary Power Units;* Direct-fired Heaters (with or without Thermal Storage Units | E* |
| Air Conditioning System Improvement | Enhanced Air Conditioning System (to reduce Direct Emissions# or Indirect Emissions); Alternative Refrigerants: CO2;*, # HFC-152a;*, # HC*, # | E*
I# |
| Aerodynamic Drag Reduction | Vehicle Profile Improvement (Tractor; Truck Side and Underside;# Trailer or Van); Pneumatic Aerodynamic Drag Reduction;*, # Planar Boat Tail Plates on a Tractor-trailer; Vehicle Load Profile Improvement* | E*
I#
 |
| Tire Rolling Resistance Improvement | Automatic Tire Inflation Systems; Wide-base Tires;* Low-Rolling-Resistance Tires;* Pneumatic Blowing to Reducing Rolling Resistance | E* |

- E *= mutually exclusive within a subgroup; I# = interaction within a subgroup.

## List of 33 Best Practices for the Truck Mode (Continued)

| Subgroup | Names of Best Practices | Note |
| --- | --- | --- |
| Hybrid Propulsion | Hybrid Trucks |  |
| Weight Reduction | Lightweight Materials |  |
| Transmission Improvement | Advanced Transmission; # Low-viscosity Transmission Lubricants# | I# |
| Diesel Engine Improvement | Low-viscosity Engine Lubricants; Increased Peak Cylinder Pressures; Improved Fuel Injectors; # Turbocharged, Direct Injection to Improved Thermal Management; # Thermoelectric Technology to Recovery Waste Heat | I#
 |
| Accessory Load Reduction | Electric Auxiliaries;*, # Fuel-cell-operated Auxiliaries*, # | E*
I# |
| Driver Operation Improvement | Truck Driver Training Program |  |
| Alternative Fuel | B20 Biodiesel Fuel for Trucks |  |

- E* = mutually exclusive within a subgroup; I# = interaction within a subgroup.

## List of 6 Best Practices for the Rail Mode

| Subgroup | Names of Best Practices | Note |
| --- | --- | --- |
| Anti-idling | Combined Diesel Powered Heating System and Auto Engine Start/stop System;* Battery-diesel Hybrid Switching Locomotive;* Plug-in Units* | E* |
| Weight Reduction | Lightweight Materials |  |
| Rolling Resistance Improvement | Lubrication Improvement |  |
| Alternative Fuel | B20 Biodiesel Fuel for Locomotives |  |

- E* = mutually exclusive within a subgroup; I# = interaction within a subgroup.

## List of 10 Best Practices for the Air Mode

| Subgroup | Names of Best Practices | Note |
| --- | --- | --- |
| Aerodynamic Drag Reduction | Surface Grooves; Hybrid Laminar Flow Technology; Blended Winglet;* Spiroid Tip* | E* |
| Air Traffic Management Improvement | Air Traffic Management Improvement |  |
| Weight reduction | Airframe Weight Reduction; Non-essential Weight Reduction |  |
| Ground Support Equipment Improvement | Ground-based Equipment as an Alternative to Auxiliary Power Units; Electric or Hybrid Heavy Duty Delivery Trucks |  |
| Engine Improvement | Improved Engine Combustion Efficiency |  |

- E* = mutually exclusive within a subgroup; I# = interaction within a subgroup.

## List of 5 Best Practices for the Water Mode

| Subgroup | Names of Best Practices | Note |
| --- | --- | --- |
| Propeller System Improvement | Off-center Propeller;* Propeller Boss Cap with Fins;* Auxiliary Free-rotating Propulsion Device behind the Main Propeller* | E* |
| Anti-idling | Shoreside Power for Marine Vessels at Ports |  |
| Alternative Fuel | B20 Biodiesel Fuel for Ships |  |

- E* = mutually exclusive within a subgroup; I# = interaction within a subgroup.

## List of 5 Best Practices for the Pipeline Mode

| Subgroup | Names of Best Practices | Note |
| --- | --- | --- |
| Process Control Device Improvement | Convert Natural Gas Pneumatic Controls to Instrument Air; Replace High-bleed Natural Gas Pneumatic Devices with Low-bleed Pneumatic Devices |  |
| Connecting Method | “Hot Tap” Method |  |
| Maintenance |  Transfer Compression; Inline Inspection |  |

## Total 2025 Modal GHG Emissions Reductions Compared to 2025 Without Best Practices

- GHG Emissions
- Reductions (%)

## Total 2025 Modal GHG Emissions ReductionsCompared to 2025 Without Best Practices

- Reductions in Total Modal GHG
- Emissions (Million Tons CO2 eq.)

## Changes in GHG Emissions from 2003 to 2025 with Best Practices

- Total Modal GHG Emissions
- (Million Tons CO2 eq.)

## Changes in GHG Emissions from 2003 to 2025 with Best Practices

- Percentage Change (%)

## Comparisons of Best Practices Assessed Quantitatively

- To date, sufficient information has been obtained to assess 13 practices quantitatively.

| Mode | Name of Best Practices |
| --- | --- |
| Truck | 1. Off-board Truck Stop Electrification
2. Auxiliary Power Units
3. Direct-fired Heaters
4. Hybrid Trucks
5. B20 Biodiesel |
| Rail | 6. Combined Diesel Powered Heating and Start/stop System
7. Battery-diesel Hybrid Switching Locomotive
8. Plug-in Units
9. B20 Biodiesel |

## Comparisons of Best Practices Assessed Quantitatively (Continued)

| Mode | Names of Best Practices |
| --- | --- |
| Water | 10. B20 Biodiesel |
| Pipeline | 11. Natural Gas-powered Pipeline Process Control Device: replaced by compressed air-powered
12. Natural Gas-powered Pipeline Process Control Device: replaced by low-bleed pneumatic devices;
13. “Hot Tap” Method |

## Comparison of Best Practices Assessed Quantitatively (Continue)

-  (Million Tons CO2 eq. / Year)

- Truck

**Comparison of Best Practices Assessed Quantitatively (Continue)**

- Rail

- Water

- Pipeline

- Auxiliary
- Power
- Units

- Hybrid
- Trucks

- B20 Biodiesel

## Comparisons of Best Practices Assessed Quantitatively (Continued)

- Truck

**Comparisons of Best Practices Assessed Quantitatively (Continued)**

- Rail

- Water

- Pipeline

- Auxiliary
- Power
- Units

- Hybrid
- Trucks

- B20
- Bio-
- diesel

## Inter-Modal Comparison of Average ModalGHG Emission Rates

- GHG Emissions per Unit of Freight Transport (lb CO2 eq. / ton-mile)

## Overview of the Organization and Content of The Guidebook

**Overview of the Organization and Content of The Guidebook**

- Definitions and

- Concepts

**Chapter 2**

- Methodology

**Chapter 3**

- Fuel Properties

**Appendix F**

**Background and Methodology**

**Assessments of Individual and Subgroups of **

**Best Practices by Mode**

- Mode

- Summary Material

- Supporting Details

- Truck

**Chapter 4**

**Appendix A**

- Rail

**Chapter 5**

**Appendix B**

- Air

**Chapter 6**

**Appendix C**

- Water

**Chapter 7**

**Appendix D**

- Pipeline

**Chapter 8**

**Appendix E**

- Summaries of and

- Comparisons

- Between Modes

**Chapter 9**

- Conclusions and

- Recommendations

**Chapter 10**

## Conclusions

- Aggressive implementation of best practices may lead to a *net decrease* in total GHG emissions in freight transportation
- Even larger percentage reductions are possible if Inter-modal shifts (e.g., substitute rail for truck) are encourage

## Conclusions

- There is limited quantitative data upon which to base assessments of best practices
- For 13 best practices for which adequate data are available:
-   - The normalized cost savings per unit of GHG
-      emissions reduction was highly variable
-   - The variability mostly depends on the magnitudes
-      of their energy cost savings.

## Conclusions

- Some best practices (e.g., biodiesel for trucks) offer potential for large magnitudes in GHG emissions reductions, but may not be as cost-effective
- From a national policy perspective, governments should promote research, development, and demonstration (RD&D) to foster best practices that lead to large absolute reductions in GHG emissions
- Some best practices may lead to “no regrets”
- e.g., net cost savings to an operator
- Additional benefits of GHG emissions or energy use reduction

## Recommendations

- Update information as new information becomes available
- Evaluate key assumptions (e.g., market penetration rates) that influence the selection of best practices via sensitivity analysis
- Develop tools (e.g., a decision tree, a decision support framework) to support decision making regarding best practices

## Acknowledgement/Disclaimer

- This work is supported by the U.S. Department of Transportation via Center for Transportation and the Environment.
- The authors are responsible for the facts and accuracy of the data presented herein.
- The contents do not necessarily reflect the official views or policies of either the U.S. Department of Transportation or the Center for Transportation and the Environment at the time of publication.
- This report does not constitute a standard, specification, or regulation.