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Vehicle Transport System by Sharing, Electrification and
Automatization
Toshiyuki YamamotoNagoya University
1
CASE
• Connected
• Autonomous
• Shared
• Electric
2
C
A
S
E
“Connected, Autonomous, Shared, Electric: Each of these has the power to turn our entire industry upside down. But the true revolution is in combining them in a comprehensive, seamless package.” by Dr. Dieter Zetsche (Chairman of the Board of Management of Daimler AG)
Shared autonomous vehicles
3
A
S
Automation levels (SAE)
4
Source: https://www.nhtsa.gov/technology-innovation/automated-vehicles-safety
Level3
2020
Level 4
2025Target year in Japan
Car sharing• The fleet is made available for use by members of
the car sharing organization• Merits: Rational mode choice, decrease car
dependency, fuel efficient vehicle, save parking space, etc.
5Car sharing in Japan
(Source: Foundation for Promoting Personal Mobility and Ecological Transportation)
0200,000400,000600,000800,0001,000,0001,200,000
05,000
10,00015,00020,00025,00030,000
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
Mem
bers
hip
(per
son)
Flee
t size
(veh
icle
)
Year
Fleet size (vehicle)Membership (person)
A
S
Weak point of car sharing
• One-way system is more convenient for users than return-only system
• But, one-way operation causes imbalance of fleet, deteriorating efficiency
6
Autonomous vehicle can relocate by themselves
Objective
Forecast supply and demand of shared autonomous vehicles
• Probability for sharing private cars• Potential demand for driverless taxi• Required fleet size
7
Study area
Meito Ward, Nagoya, Japan• Area: 19.45 km2
• Population: 164,570• East-end of Nagoya City• Residential area• Good access to CBD by
subway
8
Sharing of private autonomous cars
9
Uber:Private car driven by
human driver as taxi
Shared private autonomous
car:private
autonomous car used as taxi at spare time
Now Future
Framework
Car ownershipand shared use
Mode choice Traffic network
10
Car availability
Traffic demand
CongestionWaiting timeFleet supply
• Interaction is roughly considered• Equilibrium state is not rigorously calculated
Revenue
Intention for autonomous vehicle ownership & shared use (N=803)
• 70,000 Private cars in the area -> 9100 potential shared cars-> Driverless taxis system can be organized by them 11
Own car w/o share55%
Own car & share it
13%
Don't own & use shared
car32%
Age difference in intention
12
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
20s
30s
40s
50s
60+
Own car w/o share Own car & share it Don't own & use shared car
Current car use (or non-use)
• 14 & 13 hrs. at garage on weekday and weekend on average• 10 & 14% of households don’t use car on weekday and
weekend 13
0 50 100 150 200 250
Almost everyday4-5 days/week2-3 days/week
1 day/week1 day/2-3 weeks
1 day/month1 day/2-3 months
1 day/half year1 day/year
Less than aboveNo drive
No license
Drive frequency
0 50 100 150
Not fixed
3
6
9
12
15
18
21
24
Car at garage (hours/day)
Weekend Weekday
Z Z z…
Expected monthly income by sharing
14
3,000JPY13% 5,000JPY
11%
10,000JPY17%
15,000JPY11%
20,000JPY36%
30,000+JPY9%
Other3%
• Assumed to provide your private car for 5 hrs. each day
Nested logit model of intra-zonal travel mode choice
15By Chukyo person trip survey data in 2011
Estimation results (N=4542)Generic variable Coef.
Travel cost [100JPY] -0.126**
Travel time [hour] -0.998**
Waiting time [hour] -2.211**
16
Alternative specific variable Rail Bus Taxi Car 2wheel
Male 0.106 -0.328 0.253 0.071* -0.059*Child (<16) -2.241** -0.348* -0.785**Student -0.350* 0.335**Old (65+) 0.197 2.419** 0.805**Unemployed -0.605* 0.224 -0.163 -0.129** -0.161**Commute 1.007** 1.711** -0.141**Constant -2.199 -3.907 -0.71 0.273 -0.099
• Adjusted rho-square = 0.158• Value of time = 792 JPY/hr• Inclusive value = 0.245** (for NMT)
=1.0 (fixed for MT)
• Walk as base alternative * 5% significance, ** 1% significance
Potential demand scenarios• Cost is assumed as 55 JPY/km (slightly less than private car)• Waiting time is assumed as 1 minute• Those who own car w/o share will not use other share cars
17
Rail1.2%
Bus2.1% Taxi
0.2%
Car22.3%
Bike14.6%
Walk39.7%
SAV19.9%
Mode share
Those who own car w/o share
Waiting time won’t use will use
1 minute 22455 trips 43307 trips5 minutes 18107 trips 34005 trips
Trip demand by scenario
Agent-based simulation
18
Empty taxi En route to customer
Occupied taxi Waiting customer
• Trip demand:– Generated based on
actual OD pattern
• Vehicle agent:– Distributed based on
population distribution
• Vehicle speed:– 18.9 km/h (peak hour)– 24 km/h (off-peak)
System behavior by scenario
19
0
1
2
3
4
5
100% 75% 50%
Prob
abili
ty (%
)
Proportion of SAV supply
Probability of waiting time over 1 minutes
Waiting time: 1 min, limited user Waiting time: 5min, limited usersWaiting time: 1min, all users Waiting time: 5 min, all users
1 minute of waiting time is satisfied at 95+%
Relationship between supply and income
20
05000
100001500020000250003000035000400004500050000
30% 40% 50% 60% 70% 80% 90% 100%
MO
NTH
LY IN
CO
ME
OF
SAV
S (J
PY/C
AR
)
PROPORTION OF SAV SUPPLY
Cumulative distribution of expected income
Electrification of university car fleet: A case of Nagoya University
21
S
E
Electric vehiclesEVs (Electric vehicles)
BEVs(Battery Electric
Vehicles)
PHEVs(Plug-in Hybrid
Electric Vehicles)
HEVs(Hybrid Electric
Vehicles)
FCEVs(Fuel-Cell
Electric Vehicles)
Charging Level Type* Power
supplyCharging time
(24kWh battery) Typical use Standard
Level 1 Normal 120V AC 16 hours Home SAE J1772
Level 2 Normal 240V AC 8 hours Home or public places SAE J1772
Level 3 Fast 480V DC 30 minutes Public places CHAdeMO/CCS/Tesla
Battery charging
*Normal charging aka slow chargingFast charging aka quick or rapid charging
S
E
Anxiety about electric vehicle
• Shorter drive distance than gasoline vehicle
• Increase in electricity demand
23
Mostly short distance trips are served by car sharing
V2G can contribute peak cut of demand
Vehicle to grid (V2G)
• Batteries in EV could be used to let electricity flow from the car to the electric grid
• Provide power to help balance loads by “valley filling” and “peak-shaving”
24Source: http://www.cenex.co.uk/vehicle-to-grid/
Objective• To evaluate the reduction of CO2 emission by
replacing university car fleet with EV• To quantify electricity supply with V2G for
campus use
25
Method• Fitting the Daily Travel Distance (DTD) data with
different distribution functions• Based on the distribution function, determining the
vehicles that can be replaced by EV• Calculating electricity supply with V2G considering
usage and charging pattern
DataNagoya University’s fleet system• Observations: Oct. 2014 to Sept. 2015 with 54 vehicles• Item: department, vehicle ID, vehicle type, time of
check-out and check-in, etc.
26
Graduate School of Env. Studies 12School of Agricultural Science 10Research Institutes 10Secretariat 8Faculty of Science 5Faculty on Liberal Arts 3School of Engineering 2School of Informatics and Science 2Museum 1Physical Education Center 1
Number of vehicles by Faculty
47
25
Vehicle Type
ordinary gasolinevehicle
diesel vehicle
hybrid vehicle
Vehicle use rate by time of day
27
0%
1%
2%
3%
4%
5%
6%
7%
8%
9%
10%0
1:00
2:00
3:00
4:00
5:00
6:00
7:00
8:00
9:00
10:0
0
11:0
0
12:0
0
13:0
0
14:0
0
15:0
0
16:0
0
17:0
0
18:0
0
19:0
0
20:0
0
21:0
0
22:0
0
23:0
0
The
use
rate
Time of day
SUN MONTUE WEDTHU FRISAT
Two peaks (10:00 and 13:00) and significant drop at 12:00Consistent with people’s daily work schedule
Trip distance per check-out
2016/03/29 28
0%
10%
20%
30%
40%
50%
60%
10 20 30 40 50 60 70 80 90 100110120130140150160170180190200km
0%2%4%6%8%
10%12%14%16%
1 2 3 4 5 6 7 8 9 10km
• Mostly, vehicles are used for short distance trips
The number of vehicles used at the same time
• At maximum, 21 vehicles (out of 48) are used at the exact same hour, and it happened only once in a year. 29
0
500
1000
1500
2000
2500
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Num
ber o
f hou
rs p
er y
ear
Number of vehicles in use
The number of vehicles in use at the exact same hour
Significant number of vehicles can be reduced by implementing car-sharing system
Distribution of daily travel distance
Log-normal56.3%
Gamma18.8%
Weibull12.5%
Normal12.5%• Best fitted distribution
is chosen for each vehicle although 20 vehicles didn’t fit any at 95% confidence level
30
0
0.1
0.2
0.3
0.4
Prob
abilit
y
km
Vehicle 4637Observation Log-normal
Replace by EV
31
5 EV Scenarios• Type 1: Mitsubishi i-MiEV (100km, 16kWh)• Type 2: Chevrolet Spark EV (130km, 21kWh)• Type 3: Kia Soul EV (150km, 27kWh)• Type 4: Nissan Leaf (170km, 30kWh)• Type 5: Tesla Model 3 (320km, 60kWh)
22 23 25 2630
05
1015202530
Type 1 Type 2 Type 3 Type 4 Type 5
Num
ber o
f veh
icle
s
Type 1:i-MiEV
Type 2:Spark
Type 3:Soul
Type 4:Leaf
Type 5:Tesla
The number of vehicles that can be replaced by each type of EV
satisfying 95% of travel can be covered
CO2 reduction
14% 14% 15% 16%20%
0%
5%
10%
15%
20%
25%
Type 1:i-MiEV
Type 2:Spark
Type 3:Soul
Type 4:Leaf
Type 5:Tesla
Reduction of CO2 emission
32
Emission factorGasoline Electricity
2.3 kg/L 0.39 kg/kWh
�𝐶𝐶𝐶𝐶2 from 𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒 =𝐷𝐷𝐷𝐷𝐷𝐷
𝐷𝐷𝑒𝑒𝑒𝑒𝐷𝐷𝑒𝑒𝐷𝐷𝐷𝐷 𝑒𝑒𝑟𝑟𝐷𝐷𝐷𝐷𝑒𝑒× 𝐶𝐶 × 0.39
𝐶𝐶𝐶𝐶2 from 𝐷𝐷𝑟𝑟𝑔𝑔𝑔𝑔𝑒𝑒𝑒𝑒𝐷𝐷𝑒𝑒 = 𝐷𝐷𝐷𝐷𝐷𝐷/𝐽𝐽𝐶𝐶08 × 2.3
Vehicle to grid
33
• University provides real time data of electricity use
• Collected data from Jun 20th
2017 to Jul 9th 2017, and used the average as reference
• According to NU announcement, even 0.3% reduction at peak could be helpful for contract
02000400060008000
10000120001400016000kW
Time of Day
13561
Charge/discharge speed
34
� 𝑒𝑒𝑡𝑒𝑒 𝑔𝑔𝑠𝑠𝑒𝑒𝑒𝑒𝑠𝑠 𝑔𝑔𝑜𝑜 𝑒𝑒𝑡𝑟𝑟𝑒𝑒𝐷𝐷𝑒𝑒𝐷𝐷𝐷𝐷𝑒𝑒𝑡𝑒𝑒 𝑔𝑔𝑠𝑠𝑒𝑒𝑒𝑒𝑠𝑠 𝑔𝑔𝑜𝑜 𝑠𝑠𝑒𝑒𝑔𝑔𝑒𝑒𝑡𝑟𝑟𝑒𝑒𝐷𝐷𝑒𝑒𝐷𝐷𝐷𝐷 ⇒ 10𝑘𝑘𝑘𝑘 𝑠𝑠𝑒𝑒𝑒𝑒 𝑡𝑔𝑔𝑜𝑜𝑒𝑒S𝑠𝑠𝑒𝑒𝑒𝑒𝑠𝑠
Vehicle Battery Size
Level 2 LCS-30 5.8kW
Level 2 LCS-30 7.7kW
Level 2 LCS-30 9.6kW
Level 2 LCS-30 11.5kW
Mitsubishi i-MiEV 16kWh 5 5 5 5Chevrolet Spark EV 21kWh 7 7 7 7
Kia Soul EV 27kWh 4.5 4 4 4Nissan Leaf 30kWh 5 4.5 4.5 4.5
Tesla Model 3 60kWh 10.5 8 6.5 5
Estimated Electric Vehicle Charge Times
Source: https://www.clippercreek.com/charging-times-chart/
• Available electricity from EV is calculated according to charge/discharge speed considering vehicle usage pattern
Average available electricity by V2G
35
0
50
100
150
200
250
300
Avai
labl
e el
ectri
city
(kW
h)
Time of day
TYPE 1 TYPE 2 TYPE 3 TYPE 4 TYPE 5
Type 1:i-MiEV
Type 2:Spark
Type 3:Soul
Type 4:Leaf
Type 5:Tesla
1.21% 1.28% 1.40% 1.47% 1.72%
Peak hour
Final remark: Image of Car
36
• Status symbol• Independence• Pollution emitter
• Mobility tool• Fleet (cars)• Part of energy
management
Now Future