Well-To-Wheels Energy Use and Greenhouse Gas Emissions of Plug-in Hybrid Electric Vehicles
Amgad Elgowainy, Andy Burnham, Michael Wang, John Molburg, and Aymeric Rousseau
Center for Transportation ResearchArgonne National Laboratory
Presentation at MIT/Ford/Shell Research Workshop
June 8, 2009
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Scope of Argonne’s PHEV WTW Analysis
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To examine relative energy and emission merits of PHEVs; the vehicle types addressed were: Conventional international combustion engine vehicles (ICEVs) Regular hybrid electric vehicles (HEVs) ICE plug-in hybrid electric vehicles (PHEVs) Fuel cell (FC) PHEVs
Fuel options: Petroleum
Gasoline Diesel
E85 with ethanol from Corn Switchgrass
Hydrogen with several production pathways Electricity with different generation mixes
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Argonne’s PHEV WTW Analysis Addresses The Following Key Issues
PHEV performance evaluation with Argonne’s PSAT model Explored PHEV operating strategies Processed fuel economy results for various PHEV configurations Examined effects of all electric ranges (AER) of PHEVs
Electricity generation mixes to charge PHEVs Reviewed studies completed in this area Generated five sets of generation mixes for PHEV recharge
PHEV mileage shares by power source Relied on national average distribution of daily vehicle miles traveled (VMT) Determined VMT shares by charge depleting (CD) and charge sustaining
(CS) operations
GREET WTW simulations of PHEVs Expanded and configured GREET for PHEVs Conducted GREET PHEV WTW simulations
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Five Sets of Generation Mixes for PHEV Recharge Were Used in This Study (%)
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• US Average: the default GREET average mix for 2020• IL, NY, and CA Marginal: from the 2020 mix with 2kW charging capacity starting at 10 PM from
a study by Hadley et al.• Renewable: a scenario reflecting upper limit on benefits of PHEVs
Mix Coal Oil Natural Gas
Nuclear Other
US Average 52.5 1.3 13.5 20.1 12.6
Illinois – Region 4 (MAIN) Marginal 75.2 0.0 24.7 0.0 0.1
New York – Region 6 (NPCC-NY) Marginal 3.4 67.2 29.4 0.0 0.0
California – Region 13 (WECC-CA) Marginal 0.0 0.0 99.0 0.0 1.0
Renewable 0.0 0.0 0.0 0.0 100.0
Mix Coal Oil Natural Gas
Nuclear Other
US Average 52.5 1.3 13.5 20.1 12.6
Illinois – Region 4 (MAIN) Marginal 75.2 0.0 24.7 0.0 0.1
New York – Region 6 (NPCC-NY) Marginal 3.4 67.2 29.4 0.0 0.0
California – Region 13 (WECC-CA) Marginal 0.0 0.0 99.0 0.0 1.0
Renewable 0.0 0.0 0.0 0.0 100.0
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A Set of Vehicle/Fuel Systems Was Included in This Analysis
Vehicle types included: ICEV: Gasoline SI, E85 SI, Diesel CI HEV: Gasoline SI, E85 SI, Diesel CI; Hydrogen FC PHEV: Gasoline SI, E85 SI, Diesel CI; Hydrogen FC
Model year 2015 midsize car
Fuel economy results were adjusted using EPA 2007-adopted formula for on-road performance
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6
Fuel Consumption Calculated from PSAT Fuel Economy Values (Btu/mi)
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Fuel consumption for each operation is the following:• CD electric: electricity consumption in CD operation• CD Engine: fuel consumption by ICE/FC in CD (blended mode) operation• CS operation: fuel consumption in CS operation
AER 0 AER 10 AER 20 AER 30 AER 40
Fuel ICEV Regular Hybrid
CD Electric
CD Engine
CS Engine
CD Electric
CD Engine
CS Engine
CD Electric
CD Engine
CS Engine
CD Electric
CD Engine
CS Engine
Gasoline 3790 2680 520 1135 2590 560 1010 2600 670 725 2620 670 750 2645
E85 2840 515 1200 2740 560 1050 2750 665 760 2780 665 780 2810
Diesel 2470 535 1080 2435 575 955 2450 690 680 2470 685 710 2490
Hydrogen 1890 760 510 1895 745 595 1915 650 795 1940 735 670 1960
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PHEVs with 20-Mile AER Can Potentially Drive 40% of Daily VMT , PHEVs with 40-Mile AER More than 60%
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0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 10 20 30 40 50 60 70 80 90 100
All Electric Range (mi)
% V
MT
on
Ele
ctr
icit
y (
Uti
lity
Fa
cto
r)
NHTS
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WTW Total Energy Use for CD Mode (Electricity and Fuel) vs. CS mode (Fuel) – 20 AER; US Mix
PHEV20 - US Mix (Model Year 2015)
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
SI R
FG, C
DS
I RFG
, CS
CI L
SD
, CD
CI L
SD
, CS
SI E
85 -C
orn,
CD
SI E
85 -C
orn,
CS
SI E
85 -H
.Bio
mas
s, C
D
SI E
85 -H
.Bio
mas
s, C
SFC
H2-
Dis
tibut
ed S
MR
, CD
FC H
2- D
istib
uted
SM
R, C
SFC
H2-
Dis
tibut
ed E
lect
roly
sis,
CD
FC H
2- D
istib
uted
Ele
ctro
lysi
s, C
SFC
H2-
Cen
tral
H.B
iom
ass,
CD
FC H
2- C
entr
al H
.Bio
mas
s, C
S
To
tal E
ne
rgy
Us
e [
Btu
/mi]
PTW (On-board)
PTW (Grid Electricity)
WTP (Grid Electricity)
WTP (On-board)
9
WTW GHG Emissions for CD Mode (Electricity and Fuel) vs. CS Mode (Fuel) – 20 AER; US Mix
PHEV20 - US Mix (Model Year 2015)
-200
0
200
400
600
800
SI R
FG
, CD
SI R
FG
, CS
CI L
SD
, CD
CI L
SD
, CS
SI E
85 -
Co
rn, C
D
SI E
85 -
Co
rn, C
S
SI E
85 -
H.B
iom
ass,
CD
SI E
85 -
H.B
iom
ass,
CS
FC
H2-
Dis
tibu
ted
SM
R, C
DF
C H
2- D
istib
ute
d S
MR
, CS
FC
H2-
Dis
tibu
ted
Ele
ctro
lysi
s, C
DF
C H
2- D
istib
ute
d E
lect
roly
sis,
CS
FC
H2-
Cen
tral
H.B
iom
ass,
CD
FC
H2-
Cen
tral
H.B
iom
ass,
CS
GH
G E
mis
sio
ns
[g
/mi]
PTW (On-board)
WTP (Grid Electricity)
WTP (On-board)
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WTW GHG Emissions for CD Mode (Electricity and Fuel) vs. CS Mode (Fuel) – 20 AER; CA Mix
PHEV20 in CA (Model Year 2015)
-200
0
200
400
600
800
SI R
FG
, CD
SI R
FG
, CS
CI L
SD
, CD
CI L
SD
, CS
SI E
85 -
Co
rn, C
D
SI E
85 -
Co
rn, C
S
SI E
85 -
H.B
iom
ass,
CD
SI E
85 -
H.B
iom
ass,
CS
FC
H2-
Dis
tibu
ted
SM
R, C
DF
C H
2- D
istib
ute
d S
MR
, CS
FC
H2-
Dis
tibu
ted
Ele
ctro
lysi
s, C
DF
C H
2- D
istib
ute
d E
lect
roly
sis,
CS
FC
H2-
Cen
tral
H.B
iom
ass,
CD
FC
H2-
Cen
tral
H.B
iom
ass,
CS
GH
G E
mis
sio
ns
[g
/mi]
PTW (On-board)
WTP (Grid Electricity)
WTP (On-board)
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WTW GHG Emissions for CD Mode (Electricity and Fuel) vs. CS Mode (Fuel) – 20 AER; IL Mix
PHEV20 in IL (Model Year 2015)
-200
0
200
400
600
800
SI R
FG
, CD
SI R
FG
, CS
CI L
SD
, CD
CI L
SD
, CS
SI E
85 -
Co
rn, C
D
SI E
85 -
Co
rn, C
S
SI E
85 -
H.B
iom
ass,
CD
SI E
85 -
H.B
iom
ass,
CS
FC
H2-
Dis
tibu
ted
SM
R, C
DF
C H
2- D
istib
ute
d S
MR
, CS
FC
H2-
Dis
tibu
ted
Ele
ctro
lysi
s, C
DF
C H
2- D
istib
ute
d E
lect
roly
sis,
CS
FC
H2-
Cen
tral
H.B
iom
ass,
CD
FC
H2-
Cen
tral
H.B
iom
ass,
CS
GH
G E
mis
sio
ns
[g
/mi]
PTW (On-board)
WTP (Grid Electricity)
WTP (On-board)
0
100
200
300
400
500
600
700
0 10 20 30 40
All Electric Range [mi]
GH
G E
mis
sio
ns
[g/m
i]
ICEV SI Gasoline PHEV FC SMRPHEV FC Electrolysis PHEV FC BiomassPHEV SI Gasoline PHEV SI Corn E85PHEV CI Diesel PHEV SI Biomass E85
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WTW GHG Emissions – US Mix: Comparison of Technology and All Electric Range
Regular Hybrid
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Summary of Petroleum Energy and GHG Effects of All Evaluated Options
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
Petroleum Use (relative to GV)
GH
G E
mis
sio
ns
(re
lati
ve
to
GV
)
Baseline (GV) PHEV SI Gasoline PHEV CI Diesel PHEV SI Corn-E85 PHEV SI H. Biomass-E85 PHEV FC Distributed SMR-H2 PHEV FC Central H. Biomass-H2 PHEV FC Distributed Electrolysis-H2
Small marker for PHEV10Large marker for PHEV40
AER 0 (Regular HEV)
US Ave. Mix
CA Mix
NY Mix
IL Mix
Renewable
[ VMTCD / VMTtotal ]PHEV10 = 23%
[ VMTCD / VMTtotal ]PHEV40 = 63%
Petroleum Fuels
E85
H2
color/pattern of marker = fuel/vehicle typeshape of marker = electricity generation mixsize of marker = AER rating
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
Petroleum Use (relative to GV)
GH
G E
mis
sio
ns
(re
lati
ve
to
GV
)
Baseline (GV) PHEV SI Gasoline PHEV CI Diesel PHEV SI Corn-E85 PHEV SI H. Biomass-E85 PHEV FC Distributed SMR-H2 PHEV FC Central H. Biomass-H2 PHEV FC Distributed Electrolysis-H2
Small marker for PHEV10Large marker for PHEV40
AER 0 (Regular HEV)
US Ave. Mix
CA Mix
NY Mix
IL Mix
Renewable
[ VMTCD / VMTtotal ]PHEV10 = 23%
[ VMTCD / VMTtotal ]PHEV40 = 63%
Petroleum Fuels
E85
H2
color/pattern of marker = fuel/vehicle typeshape of marker = electricity generation mixsize of marker = AER rating
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Thank you!
GREET web site:http://www.transportation.anl.gov/modeling_simulation/GREET/index.html
PHEV WTW Analysis Report:http://www.transportation.anl.gov/pdfs/TA/559.pdf
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PSAT Fuel Economy Results (Miles Per Gasoline Equivalent Gallon, Wh/Mile for CD Electric Operation)
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• CD Electric = charge depleting operation with grid electricity
• CD Engine = charging depleting operation with on-board power systems (ICE or Fuel Cell)
• CS = charge sustaining operation with on-board power systems
• AER 0 = zero-mile AER (i.e., regular HEV)
• AER 10 = 10-mile AER; AER 20 = 20-mile AER; AER 30 = 30-mile AER; AER 40 = 40-mile AER
• UDDS = Urban Dynamometer Driving Schedule; HWFET = Highway Fuel Economy Test
CD electric operation and CD on-board operation complement each other for the same CD miles (i.e., blended mode operation)
ICEV AER 0 AER 10 AER 20 AER 30 AER 40
Regular Hybrid
CD Electric
CD Engine
CS Engine
CD Electric
CD Engine
CS Engine
CD Electric
CD Engine
CS Engine
CD Electric
CD Engine
CS Engine
UDDS 27.6 45.6 148.1 132.4 47.1 141.3 122.3 46.9 174.1 184.3 46.6 165.1 153.4 46.2 Gasoline ICE
HWFET 34.0 39.7 107.8 78.3 41.1 136.9 103.9 41.0 158.2 134.5 40.6 168.0 152.6 40.2
UDDS 42.9 146.1 125.5 44.4 141.2 118.4 44.2 172.6 179.7 43.8 164.3 148.6 43.4 E85 ICE
HWFET 37.5 106.3 73.8 38.9 136.9 99.3 38.8 156.8 126.2 38.3 167.0 144.4 37.9
UDDS 49.4 151.4 138.1 50.0 144.7 127.5 49.7 179.7 191.3 49.3 169.7 158.7 48.9 Diesel ICE
HWFET 43.0 110.2 84.1 43.8 140.3 112.2 43.6 163.3 145.7 43.2 172.6 164.5 42.9
UDDS 59.4 157.7 132.6 59.5 154.2 123.4 58.8 156.2 120.7 58.1 181.8 142.7 57.3 H2 FC
HWFET 62.3 229.4 1514.4 61.5 224.0 601.5 60.9 170.1 189.6 60.3 184.7 225.4 59.7
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Processing of PSAT MPG Results for GREET Fuel Consumption Inputs
PSAT fuel economy results were first converted into fuel consumption
The city (UDDS) and highway (HWFET) results of PSAT were combined with 55% UDDS and 45% HWFET
The PSAT results for CD electric operation did not include charging losses; we assumed a 85% efficient charger
PSAT fuel consumption for CD and CS operations were combined using the “Utility Factor” (FCCDGrid + FCCDICE
)* UF + FCCS * (1-UF)
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Concluding Remarks
PSAT simulations of the blended mode operation of PHEVs show that grid electricity accounts for a small share of total vehicle energy use in combined CD and CS operations (~6% for PHEV10 and ~24% for PHEV40)
The effect of electric generation mix becomes smaller with the blended mode operation; However, electric generation mix is still shown to have a significant effects on WTW results, especially for GHG emissions Petroleum use declines when electricity is generated from non-petroleum sources GHGs are highest with large coal shares, but decreased with NG, and decreased even further with
renewables
HEV vs. PHEV Petroleum use decreases as AER increases (except for generation mixes with high share of oil) GHGs in general decrease as AER increases (except for carbon intensive generation mixes and
biomass-to-E85 and H2)
Gasoline ICE PHEV vs. FC PHEV FC PHEVs have much lower petroleum energy use FC PHEVs using SMR-H2 slightly reduce GHGs; Biomass-to-H2 FC PHEVs significantly reduce
GHGs
Outstanding issues Electric generation mix for recharging PHEVs is affected by many factors: total electricity demand by
PHEVs, location of PHEVs, time of day for recharging, PHEV buffer ability for the utility system Utility dispatch modeling may be necessary for further analysis
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