Energy Efficiency through Automation

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Motivation for full automation – we need it …
yesterday & tomorrow
Energy Efficiency through Automation
Tyler Folsom, PhD, PE
QUEST Integrated, Inc.
91st Meeting of the Transportation Research Board of the
National Academy
Jan. 22, 2012, Washington DC
Time Frames
•
•
•
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Business: Next quarter; fiscal year
Politics: Next election
Transportation planners: 30 years
Iroquois nation: 7th generation
$$$
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“The economy is a wholly owned subsidiary of the
ecosystem.” - Robert F. Kennedy Jr.
Lovins in “Reinventing Fire” finds that it is possible
for the U.S. to eliminate all petroleum, coal and
nuclear energy by 2050 with a savings of $3.8T in
transportation while increasing transport volume.
Renewable energy is more job intensive than oil or
coal.
Gilbert and Perl in “Transport Revolutions” chart
how the U.S. and China can each eliminate oil by
2030.
National Security
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European countries fought wars over access to
salt.
Making oil no more strategic than salt
eliminates the need to protect resources
militarily.
There is evidence that the demand for oil is
peaking before the supply peaks.
A gallon of gasoline delivered to Afghanistan
costs $25 to $45.
Reasons to eliminate oil
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Environmental: Pollution, sustainability, global
warming
National security: Devalue the principal asset
of unfriendly countries
Business: High oil prices, high oil volatility,
better opportunities elsewhere
WIKISPEED
Announced cars
Electric
Year
Price
Range
Tesla roadster
2008
$100,009
244
Nissan Leaf
2011
$33,000
100
Mitsubishi MiEV
2009
$29,000
62-100
Coda
2012
$41,000
150
Toyota Scion IQ
2012
BMW i3
2013
$35,000
100
Plug-in hybrids
Year
Price
Range
Chevy Volt
2011
$40,000
40
Toyota Prius plug-in
2012
$32,000
15
Gasoline
Year
Price
mpg
Volkswagen SL1
2013
50
230
Transport Revolutions
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Britain's move to railways, starting in 1830.
Substantial reversal of automobile travel in the
U.S. during World War II.
The change from ships to planes for
transatlantic travel.
The introduction of high speed rail from 1960
to 1985.
The use of air freight starting in 1980.
U.S. driving habits
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•
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•
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5% use mass transit.
Average bus occupancy is 8.8 people.
88% drive to work with 76% traveling alone.
Average trip to work is 12 mi @ 28 mph.
19% of trips are to work.
30% of trips are social and recreational.
Average car occupancy is 1.57 people.
65% of miles driven are urban.
Energy to move vehicle
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Power = K1*V + K2 * V3
For a car, rolling resistance is dominant until
35 mph.
For a light vehicle, air drag takes over at 12
mph.
Energy to overcome rolling
resistance
dW/dt = CV/η Σm·g[CR+s/100+a/g(1+mW/Σm)]
CV: Speed of vehicle
η: Overall mechanical efficiency of transmission
Σm: Total mass of vehicle, rider and baggage
g: Gravitational acceleration
CR: Coefficient of rolling resistance
s: Upslope (%)
a: vehicle acceleration
mW: Effective rotational mass of wheels
Safety allows smaller vehicles
• 93% of accidents are caused wholly or in part
by human factors.
• 41% of fatal accidents involve alcohol.
• Annual U.S. economic cost of accidents is
$230B.
• Autonomous trains are an order of magnitude
safer than manual trains.
• When all vehicles are computer controlled, a
motorcycle is almost as safe as an SUV.
Energy to overcome
aerodynamic drag
dW/dt = 0.5 CV/η CD A ρ (CV+CW)2
CV: Speed of vehicle
η: Overall mechanical efficiency of transmission
CD: Aerodynamic drag coefficient
A: Frontal area of vehicle and rider
ρ: Air density
CW: Headwind
Drag coefficients
Motorcycle
1.8
Bicycle
1.1
Bus
0.6 – 0.8
Toyota Prius
0.26
Pod car
0.20
Urbee
0.15
Supersonic
fighter
0.016
•Urbee is a two passenger car designed for
sustainability
City driving cycles
U.S.A.
Europe
Japan
Average
speed (mph)
19
20
15
Maximum
speed (mph)
56
74
43
Time stopped or
decelerating (%)
43
25
52
Typical light rail: 15.5 mile line.
Scheduled time is 38 minutes.
Average speed = 24.5 mph or 22 mph with wait.
1000 mpg is possible
• An electric pod-car has travelled 62 miles in
one hour on two ordinary lead-acid batteries;
equivalent to 2200 mpg.
• Practical vehicles weighing less than the rider
can achieve a 30 mile range from a 20 lb
battery; refueling by battery swap becomes
practical.
• Even if pod-car electricity comes from coal,
U.S. carbon savings can be equivalent to 12
trains of 100 coal cars daily.
Details and references
T. C. Folsom, Social Implications of Autonomous
Urban Land Vehicles, IEEE Technology and
Society Magazine, Spring, 2012.
T.Folsom @ qi2. com
www. enviroteach. com
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