Refueling in Winnipeg:How Long & How Often?

PHEV Recharging and Vehicle Refueling

• What is the connection? Why are we studying petroleum refueling habits?

• Because we are working under the assumption that drivers will want to

change their current behavior as little as possible – we think that recharging could

be as convenient as refueling.

Method

• Using AUTO-21 data from the University of Winnipeg Otto driving study – 44 million data points from 76 drivers over 1 year, at 1

second intervals

• Determining the ‘refueling events’ – how can we tell if someone is putting gasoline in their vehicle? Criterion: – Stopped for 1-30 minutes– Parked in a gas station, mapped in ArcMap– At least one day apart

Problems??

• Data error in the original data set– Multi-path error in the GPS data– Gas Stations are almost all under a roof!

• Non-refueling events occurring at gas stations– Gas stations may have associated convenience

shops– For example, one volunteer maked 51 stops 3 days or

less apart from each other!• Smokes, slurpees, work related?

Some Stations have well fitting refueling stopswhere the stops are obviously refueling stops.

Other stations have points which weremore ambiguous.

RESULTS!

How long do we refuel for?

• Duration of refueling events measured in minutes

• Histogram of refueling durations produced and the questions arising…– No one-minute refueling stops?– Peak at 4 minutes– Most stops < 10 minutes

Frequency of Stops by Length of Refueling stop

0

50

100

150

200

250

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

Length of Stop (minutes)

Fre

qu

ency

How Often Do We Refuel?

• Measured in Days Between Refueling Events (DBRE)

• About equally likely to refuel for each of the first 10 days, then less likely for each day after that.

Cumulative Probability of Refueling as a Function of DBREy = -0.0017x2 + 0.0747x - 0.0446

R2 = 0.998

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1 6 11 16

DBRE

Cum

ulat

ive

Pro

babi

lity

The probability of refueling after x days (on the x-axis) is well-described as a function of DBRE alone: 99.8% of the time, the probability of refueling after x days is

PR = -0.0017(x^2) + 0.0747x – 0.0446

Can Recharging be similar to Refueling?

• Mean Refueling Time in Winnipeg: 4.971 minutes

• MINIMUM Recharging Time with Level 2 – 240V, 30A – Recharging Infrastructure (for an economy-sized sedan with a battery capable of powering the vehicle 16km) : 30 minutes

PHEV Level 3 Recharging Stations

Charging

• Level 3 Charging is not a viable option, according to the US Government’s Plug-in Hybrid Electric Vehicle Charging Infrastructure Review

• Level 2 Commercial Charging combined with Level 1 Opportunity Charging is the most economical and effective option

Can Recharging be similar to Refueling?

• Median DBRE for Winnipeg drivers: 10

• Compare this to PHEVs, which would likely need to be recharged each day that they are driven!

Topics to Address in the Future…

Winnipeg & Climate

• Winnipeg’s Cold Climate!

• 5 consecutive months with Min Temperature < -10 (C)

• How does this affect battery performance in PHEVs?

Winnipeg’s Climate

PHEV viability

Two possible paths:

• We change our driving behavior to fit the needs of PHEV technology

• We change PHEV technology to adapt to our behavior