tyler c. folsom, phd, pe project manager, qi2, kent, wa professor, university of washington,...
TRANSCRIPT
Planning for Automated Vehicle Technologies
Impact on Energy
Tyler C. Folsom, PhD, PE
Project Manager, Qi2, Kent, WA
Professor, University of Washington, Bothell, WA
Easy predictions:
Safer roads Self-driving taxis blur the distinction
between public and private transportation
Less need for parking
Four Futures
1. Cars with improved Driver Assistance Systems (DAS) but still requiring a driver.
2. Cars that typically drive themselves; no license required.
3. Transit based vehicle automation.4. People moving from fixed homes to
automated Recreational Vehicles. (requires #2)
Why do big cars appeal?
Be able to haul peak load and passengers
SafetyComfortStatus
Automation supports smaller vehicles
Base two-person pods can connect to form larger vehicles.
The vehicle can be right-sized for the task at hand.
If traffic accidents are rare, a motorcycle is almost as safe as an SUV.
Small vehicles need not be cramped or Spartan.
Ultra-light PRT+
Reduced car ownership Motorcycles that are almost as safe as an
SUV Post-automotive cities Energy efficiency of 1000 (one thousand)
mpg equivalent [1] Urban transportation based on renewable
electricity Increased highway capacity with no new
construction [2] Public transportation more convenient,
faster, safer and cheaper than private transportation
Typical urban car average speeds
Location Mi/h km/h Notes
U.S. average commute
28 45 Average trip length is 12 mi. [3]
U.S. EPA city fuel rating
19 31 City driving cycle assumes 43% stopped or decelerating [4]
Japan city fuel rating 15 24 52% stopped or decelerating [4]
Mumbai, India 5-19 8-30 Minimum and maximum average speed [5].
Yakima, WA, USA 23.9 38.5 Average of 44 segments posted for 35 mph during PM peak. [6]
Typical light rail average speeds
Location Mi/h km/h Notes
Tokyo, Japan 16 26 Marunouchi line from Kasumigaseki to Ikebukuro travels 10.8 km in 25 minutes
New York City, USA 17.4 28.1 Average subway scheduled speed [7]
Seattle, USA 22 35 Downtown to airport is 15.5 mi, scheduled in 38 minutes plus 5 minute average wait time [8].
Vancouver, Canada 28 45 Does not include wait times
MARTA, Atlanta, USA 28.8 46.5 Average scheduled speed [7]
Washington, DC, USA 29.5 47.6 Average scheduled speed [7]
Typical light rail average speeds
Power to move a land vehiclePower = K1 * m * v + K2 * v3
Rolling + Aerodynamic
m: mass; v: velocity
The less-simplified version needs additional rolling power to overcome slopes or stop-and-go [9].
Ultra-light Electric Transit Predictions
Once there is a large pool of depleted batteries, energy can be harvested any time the sun shines or the wind blows.
Major reduction in fossil fuel consumption.
Less air and water pollution; improved public health.
Fewer green-house gasses.Oil is no longer a strategic commodity,
and military spending can decrease.
Possible Planning Implications Less required parking. A few remote
lots, rather than at each building. Human-scaled communities? Increased / decreased sprawl? Parking for vehicular homeless? Distributed solar & wind power
generation? Reduced need for heavy buses /
trucks → lighter roads?
Sources
[1] Tyler C. Folsom, Energy and Autonomous Vehicles, IEEE Technology and Society Magazine, Summer 2012, draft on www.qi2.com/index.php/transportation
[2] S. E. Shladover, “Reasons for operating AHS vehicles in platoons”, in Automated Highway Systems, P.A. Ioannou, Ed, New York, NY, Springer, 1996.
[3] Federal Highway Administration (2009) Summary of Travel Trends – 2009 National Household Travel Survey.
[4] S. C. Davis, S. W. Diegel and R. G. Boundy, Transportation Energy Data Book: Edition 29. July 2010 table 4.32. online cta.ornl.gov/data
[5] http://articles.timesofindia.indiatimes.com/2012-01-18/mumbai/30638447_1_kmph-coastal-road-travel-speed
[6] City of Yakima, Travel Speed Study of Urban Streets Using GPS and GIS, 2002. http://www.yakimawa.gov/services/gis/files/2012/05/reportman.pdf
[7] Matt Johnson, Average scheduled speed: How does Metro compare? 2012. http://greatergreaterwashington.org/post/5183/average-schedule-speed-how-does-metro-compare/
[8] http://www.soundtransit.org/Rider-Guide/Link-light-rail[9] F.R. Whitt and D.G. Wilson, Bicycling Science, 2nd ed, Cambridge, MA:
MIT Press 1982.