December 5, 2000 1

Heavy Truck Fuel Savingsthrough the application of

Surface Wind Forecasts

Case Study/DemonstrationRobert Wright

Planning Systems Incorporated7923 Jones Branch Drive

McLean, Virginia 22102-3304(703) 734-3446

rwright@plansys.com

December 5, 2000 2

• Weather/Wind Forecasts - Applied Successfully for Military Aircraft & Ship Operations -- e.g., Optimum Path Aircraft Routing System (Air Transportation) -- e.g., Optimum Track Ship Routing (Sea Transportation) - Forecast Wind Fields Impact Routes/Scheduling -- Optimize for:

Minimum Fuel• Similar Application for Land Transportation Commercial Heavy Trucking Operations - Long Haul - Determine Optimum (Minimum Fuel) Schedule/Route Based On :

Route Forecast Surface Winds (head/tail and cross) Truck Highway SpeedAerodynamic Drag (truck /trailer type and configuration )

CONCEPT

December 5, 2000 3

• Application when Forecast Surface Winds: - Strong (significant impact on fuel consumption) - Change in Time (significant change in fuel consumption) - Verify (reliable prediction of fuel consumption change)

• Long Haul Trucking Operations: Flexibility = Fuel Savings - Departure Scheduling: -- Take Advantage of Periods of Predicted Minimum Fuel Consumption

-- Avoid Periods of Predicted Maximum Fuel Consumption

- Route Selection: -- Take Advantage of Routes with Predicted Minimum Fuel Consumption

-- Avoid Routes with Predicted Maximum Fuel Consumption -- Applicable for Longer, Cross-Country Routes; use Longer Lead-Time Forecasts

CONCEPT

December 5, 2000 4

DEMONSTRATIONFuel Consumption versus Departure Time

WeatherTypical, Early Spring,Midwest Low PressureSystem

Rapid Movement from SE Colorado to Central Wisconsin - 05 April through 06 April 1999 Representative Surface Wind Fields (30 meter elevation) - 5th-Generation NCAR/Penn State Mesoscale Model (MM5) - Analysis: 05 April 1999/0600Z - Forecasts: Every 3 Hours: 0900Z, 1200Z, 1500Z, etc. - Model Horizontal Grid Resolution: 22.4 Miles (36 KM)

TruckModern Diesel-PoweredTractor-Trailer

Class 8 Tractor-Trailer - Weight: 80,000 Pounds - Drag Coefficient (CD): 0.6 - Power: Turbocharged Diesel Engine with 0.048 gal/HP-hr Specific Fuel Consumption

RouteCheyenne, Wyoming toOmaha, Nebraska onInterstate-80

East-West MM5 Model Grid Line Approximation of Interstate-80 Route Total Grid Line Distance: 492 Miles - 22 Segments; Each 22.4 Miles (36KM) Long

December 5, 2000 5

• Representative Drive Model - Average Highway Speed: 67 MPH - Total Time: 10 Hours -- 4 Drive Segments:

2 Hours (134.1 Miles)1 Hour 40 Minutes (111.8 Miles)2 Hours (134.1 Miles)1 Hour 40 Minutes (111.8 Miles)

-- 3 Intervening Rest Periods 40 Minutes, 1 Hour, 1 Hour

• Head/Tail Wind Forecast Synchronized with Truck Location/Time - Time-Phased Integration of Drive Model and Forecast Wind Fields

DEMONSTRATIONFuel Consumption versus Departure Time

December 5, 2000 6

NOAA NWS Daily Weather Map, 05 April 1999/1200Z

Interstate-80Cheyenneto Omaha

December 5, 2000 7

NOAA NWS Daily Weather Map, 06 April 1999/1200Z

Interstate-80Cheyenneto Omaha

December 5, 2000 8

MM5 Analysis 05 Apr 99/0600Z

MM5 Grid Line

Cheyenneto

Omaha

Truck Vector67 MPH

December 5, 2000 9

MM5 Forecast 05 Apr 99/1200Z

MM5 Grid Line

Cheyenneto

Omaha

Truck Vector67 MPH

December 5, 2000 10

MM5 Forecast 05 Apr 99/1800Z

MM5 Grid Line

Cheyenneto

Omaha

Truck Vector67 MPH

December 5, 2000 11

MM5 Forecast 06 Apr 99/0000Z

MM5 Grid Line

Cheyenneto

Omaha

Truck Vector67 MPH

December 5, 2000 12

MM5 Forecast 06 Apr 99/0600Z

MM5 Grid Line

Cheyenneto

Omaha

Truck Vector67 MPH

December 5, 2000 13

Route Segment Head(-)/Tail(+) WindsCheyenne to Omaha

At Indicated Time Time-Phased with Drive Model [Truck Departs at Indicated Time]

05 Apr 99/0600Z

-40

-30

-20

-10

0

10

20

30

40

1 3 5 7 9 11 13 15 17 19 21

Route Segment

Win

d S

pe

ed

(M

PH

)

05 Apr 99/1200Z

-40

-30

-20

-10

0

10

20

30

40

1 3 5 7 9 11 13 15 17 19 21

Route Segment

Win

d S

pe

ed

(M

PH

)

December 5, 2000 14

Route Segment Head(-)/Tail(+) WindsCheyenne to Omaha

At Indicated Time Time-Phased with Drive Model [Truck Departs at Indicated Time]

05 Apr 99/1800Z

-40

-30

-20

-10

0

10

20

30

40

1 3 5 7 9 11 13 15 17 19 21

Route Segment

Win

d S

pe

ed

(M

PH

)

06 Apr 99/0000Z

-40

-30

-20

-10

0

10

20

30

40

1 3 5 7 9 11 13 15 17 19 21

Route Segment

Win

d S

pe

ed

(M

PH

)

December 5, 2000 15

Horsepower Contributions

0

50

100

150

200

250

300

350

20 30 40 50 60 70 80 90

Level Highway Speed, MPH

Aerodynamic Drag CD=0.6

Rolling Friction&

Accessories

Horsepower Required to Overcome Aerodynamic Drag and Rolling Friction/AccessoriesClass 8 Tractor-Trailer: 80,000 Pounds

Courtesy/Permission Professor Fred BrowandUniversity of Southern California, Los AngelesDOE Heavy Vehicle Aerodynamic Drag Projectfrom A Multi-Year Program Plan for the AerodynamicDesign of Heavy Vehicles

Assumptions: Cross-Wind Does Not Affect:• CD

• Rolling Friction

December 5, 2000 16

Relative Wind Fuel Consumption

Fuel Consumption to Overcome Aerodynamic Drag and Rolling Friction/AccessoriesClass 8 Tractor-Trailer; 80,000 PoundsCD = 0.6 Highway Speed: 67 MPH

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

20 30 40 50 60 70 80 90 100 110 120

Relative Wind Speed (MPH) (Highway Speed -/+ Head/Tail Wind)

Ga

llons

pe

r M

ile

December 5, 2000 17

Total Fuel Consumed versus Departure Time

0

20

40

60

80

100

120

140

160

180

6 8 10 12 14 16 18 20 22

Departure Time (Z); 05 April 1999

Tot

al F

uel C

onsu

med

(ga

llons

)

December 5, 2000 18

Operational Implementation

• National Centers for Environmental Prediction Model Forecast Surface Wind Fields - NOAAPORT NWS Telecommunication Gateway - Eta, Nested Grid Model, Rapid Update Cycle• Compute Fuel Consumption as a Function of Possible: - Truck Types/Configurations, Routes, Departure Times• Fuel Consumption & Departure Time - Additional Parameters for Load Optimization/Scheduling Programs - For Dispatcher: Wind Optimization Feature ON or OFF

• For Independent Truckers/Small Trucking Companies - Internet Web Site - Select Truck Type/Configuration, Route, Average Speed - Display Total Fuel Consumption versus Departure Time

December 5, 2000 19

Potential Fuel Savings - Complete Study Required

• Midwest/Great Plains Interstate Highway Routes

December 5, 2000 20

Potential Fuel Savings - Study Design/Parameters

• Fall-through-Spring Period(s)• Surface Wind Analyses [e.g., FSL Hourly, 40-Km Rapid Update Cycle]• Model/Adjust Surface Winds to Truck Height• Interpolate Surface Winds to Interstate Highway Routes• Accurate Fuel Consumption Model: Include Cross-Wind Effects - Rolling Friction & Drag Coefficient • Tailor to Long Haul Centrally Dispatched Trucking Operations - Type of Trucks/Configurations (drag coefficients) - Route Traffic Density (typical number of trucks scheduled by route) - Daily Departure Times (typical number of departures by time-of-day) - Scheduling Flexibility (allowable change versus lead-time)

• Metric: Total Fuel Saved versus Change in Departure Time