1. Analysis for WLTP UF development
ACEA EV Group

2. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
The Utility Factor describes the ratio of travelled distance in
Charge Depleting Mode to total travelled distance.
max. CD range
There are several methods how the UF can be determined.

3. weighted emission [g/km]
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Basics and usage of the Utility Factor (according to US regulation)
cd-range [km] UF
100 %
phase
emission
[g/km]
weight
[%]
weighted emission [g/km] CS
150 35 53
2-4
140 5 7
2-3
124 6
2-2
100 4
2-1 3
1-4 10
1-3 14
1-2 11
1-1 13
distance[km]
3.1
4.8
7.2
8.2
phase 1 2 3 4
WLTC
total: 70
A sequential UF weights the CO2 of each CD-cycle phase with the CO2 of the CS-cycle.

4. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Different Methods for the Determination of Utility Factors
The fleet UF can only be used if the database represents a vehicle fleet of customers of a special hybrid concept.
The methodology that can be applied to the present databases to determine an average customer UF is the SAE method for the determination of the “Individual Utility Factor” (considers all vehicles equally).

5. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
impact of long distance vehicles
2 customer with average daily traveled miles of 150 km
12 customers with average daily traveled miles of 30 km UF
100 80
2 long distance vehicles reduce the UF of 12 city vehicles essentially. 60 40
UF for 12 city customers (30 km) 20
UF for the fleet
UF for 2 long distance customers (150 km) 50
100
150
electric range [km]

6. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Main database influences on the utility factor UF
WLTP charge depleting range [km]
With a constant digression of daily traveled miles the utility factor increases with a decreasing average of daily traveled miles.
average daily traveled miles
percentage UF
WLTP charge depleting range [km]
With a constant average of daily traveled miles the utility factor increases with a decreasing standard digression of the daily traveled miles.
distribution of average daily traveled miles
average daily traveled miles
percentage

7. WLTP charge depleting range [km]
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Main database influences on the utility factor UF
WLTP charge depleting range [km]
An increasing charging frequency increases the daily miles traveled in charge depleting mode. That’s the reason for an increasing UF.
charging behavior
Up to now it is not possible to validate the future OVC-HEV customers charging behavior. According to SAE J2841 the assumption of one charging event per day (overnight charge) is used for the following analysis.
Chevrolet Volt data in the EV project currently show a charging frequency 1.4 in US.
charging events
1 / day
2/ day
cd range per day

8. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Databases
Former UF analysis did not include Swedish vehicle/driver.
In addition the FIAT ECODRIVE database was analysed.
exclude N1- class vehicles (not representative for OVH-HEV customers – to be confirmed by COM)
delete drives with implausible dates
recalculation of driving days
158 of 158 vehicles
individual daily traveled miles: 58 km
fleet daily traveled miles: 49 km
milage: ~0,38 Mio. km
driving days: 7811
1275 of 1275 vehicles
individual daily traveled miles: 39 km
fleet daily traveled miles: 36 km
milage: ~1,8 Mio. km
driving days: 49769
132 of 158 vehicles
individual daily traveled miles: 46 km
fleet daily traveled miles: 47 km
milage: ~0,34 Mio. km
driving days: 7343
individual daily traveled miles: 40 km
fleet daily traveled miles: 37 km
driving days: 49043
WLTP database
FIAT ECODRIVE database
Phase 1 WLTP

9. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Distribution of daily traveled miles
Phase 1 WLTP

10. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Analysis results, pure NEDC UF versus NEDC UF corrected on WLTP
UF [%]
100 80 60 40
NEDC
WC - Compressed NEDC (UF-neutral for the reduced electric range of an WC-OVC-HEV in WLTP) 20 50
100
150
electric range [km]
Phase 1 WLTP

11. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
Analysis results, NEDC UF corrected on WLTP versus FIAT and WLTP database
UF [%]
100 80 60
Individual UF FIAT database*
Individual UF WLTP database* 40
WC - Compressed NEDC (UF-neutral for the reduced electric range of an WC-OVC-HEV in WLTP) 20 50
100
150
electric range [km]
* The lower and upper 5 % extreme customers regarding the average daily traveled distance are not included.
Phase 1 WLTP

12. Analysis for WLTP UF development
ACEA WLTP E-Lab group
Analysis for WLTP UF development
WLTP phase 2 Utility Factor
- Inclusion of charging frequency for the Utility Factor determination required.
- Statistically significant charging behavior data from the ,,EV Project’’, founded by the US Department of Energy, showed an average charging frequency of 1,4 charging events per day.
- ACEA E-Lab propose to include this recharging behavior in the methodology to determine the Utility Factor function by considering recharging at non operation times.
- ACEA E-Lab proposes the EU Commission to investigate real world EU statistical driving and recharging behavior data for OVC HEV.
Phase 2 WLTP