well-to-wheels energy and emission impacts of vehicle/fuel system; development and applications of...

8/3/2019 Well-to-Wheels Energy and Emission Impacts of Vehicle/Fuel System; Development and Applications of the GREET Model

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Well-to-Wheels Energy and Emission Impacts of

Vehicle/Fuel Systems

Development and Applications of the GREET Model

Michael Wang

Center for Transportation ResearchArgonne National Laboratory

California Air Resources Board

Sacramento, CA, April 14, 2003


2/37

Vehicle and Fuel Cycles:

Petroleum-Based Fuels

Vehicle Cycle

Fuel Cycle

Well to Pump

Pumpto

Wheels


3/37

WTW Analysis Is a Complete

Energy/Emissions Comparison

As an example, greenhouse gases are illustrated here

0

100

200

300

400

500

600

Gasoline

Vehicl

e

CornE85

Vehicl

e

Natu

ralGas

Vehicl

e

Gasolin

eFuelCel

lVehicl

e

Meth

anolFu

elCellV

ehicl

e

Eelec

tricV

ehicle,USMi

x

H2FuelC

ellVeh

icle(NG

)

H2FCV

(Electro

lysis)

GHG

Emissions(g

/mi.)

Pump to Wheels Well to Pump


4/37

WTW Analysis for Vehicle/Fuel Systems Has

Been Evolved in the Past 20 Years

Historically, evaluation of vehicle/fuel systems from wells to wheels(WTW) was called fuel-cycle analysis

Pioneer transportation WTW analyses began in 1980s

Early studies were motivated primarily by EVs

Current studies are motivated primarily by FCVs

Transportation WTW analyses have taken two general approaches

Life-cycle analysis of consumer products

Transportation fuel-cycle analysis

Most transportation studies have followed the fuel-cycle analysis approach

For transportation technologies, especially internal combustion enginetechnologies, the significant energy and emissions effects occur in thefuel usage stage first and fuel production stage second

Consequently, efforts have been in addressing energy use andemissions of vehicle operations and fuel production

Since 1995, the U.S. Department of Energy has been supporting theGREET model development at Argonne National Laboratory


5/37

The GREET (Greenhouse gases,

Regulated Emissions, and Energy use in

Transportation) Model

GREET includes emissions of greenhouse gases

CO2, CH4, and N2O VOC, CO, and NOx as optional GHGs

GREET estimates emissions of five criteria pollutants

Total and urban separately VOC, CO, NOx, Sox, and PM10 (PM2.5 not included)

GREET separates energy use into

All energy sources Fossil fuels (petroleum, natural gas, and coal)

Petroleum


6/37

The GREET Model and Its Documents

Are Available at: http://greet.anl.gov


7/37

At Present, There Are More Than 790

GREET Registered Users Worldwide

Consulting Environ Organization

Government Industry

Others University

Industries, universities, and

governmental agencies are

major GREET users

Asia North America

Europe Other

Most GREET users are in

North America


8/37

The Simplified Calculation Logicfor Individual Production Activities in GREET

Inputs

EmissionFactors

CombustionTech. Shares

Energy

Efficiencies

FacilityLocation Shares

Fuel TypeShares

Energy Use byFuel Type

TotalEmissions

UrbanEmissions

Calculations


9/37

The Simplified Calculation Logic

for Individual Transportation Activities in GREET

Energy Intensity(Btu/ton-mile)

Energy Intensity(Btu/ton-mile)

Transport

Distance (mi.)

Transport

Distance (mi.)

Energy Consumption

(Btu/mmBtu Fuel Transported)

Emission Factors

(g/mmBtu fuel burned)

Emission Factors

(g/mmBtu fuel burned)

Share ofProcess Fuels

Emissions by Mode

(g/mmBtu Fuel

Transported)

Mode ShareMode Share

Energy Use by Mode

(Btu/mmBtu Fuel Transported)

Emissions (g/mmBtu

Fuel Transported)


10/37

GREET Considers Upn Well-to-Pump

Steps Through Iteration Calculations

Feedstock

Recovery

Fuel Production

Vehicle Operation

Feedstock

Recovery

Fuel Production

Feedstock

Recovery

Fuel Production

n = 1n = 2n = 3


11/37

GREET Is Designed to

Conduct Stochastic Simulations

Distribution-Based Inputs Generate Distribution-Based Outputs


12/37

GREET Has More Than 30 Fuel Pathway Groups

Petroleum

Conv. & Reform. Gasoline

Conv. & Reform. DieselLiquefied Petroleum Gas

Compressed Natural Gas

Liquefied Natural Gas

Dimethyl Ether

MethanolFT Diesel and NaphthaNatural Gas

Gaseous and Liquid H2

Ethanol

Biodiesel

Corn

Cellulosic Biomass

Soybean

Various Sources Electricity

Flared Gas

Landfill Gas

Crude Naphtha

Liquefied Petroleum Gas

Liquefied Natural Gas

Dimethyl EtherFT Diesel and NaphthaMethanol

Gaseous and Liquid H2

Methanol

Electricity Gaseous and Liquid H2


13/37

Some Additional Fuel Production

Pathways Are to Be Added to GREET

Biomass gasification to produce Ethanol

Methanol

Hydrogen

Coal gasification to produce hydrogen

Hydrogen production from ethanol and methanol at

refueling stations Nuclear thermal cracking of water for hydrogen

production

Sodium borohydride (NaBH4) H2 production andstorage

Metal hydride hydrogen storage


14/37

Two ANL WTW Publications

Are Cited by Many Organizations

Petroleum Refining Is the


15/37

Petroleum Refining Is the

Key Energy Conversion Step for Gasoline

Petroleum Recovery (97%)

Gasoline at Refueling Stations

Petroleum Transport

and Storage (99%)

Transport, Storage, and

Distribution of Gasoline (99.5%)

MTBE or EtOH for Gasoline

WTP Overall Efficiency: 80%

Petroleum Refining to Gasoline (84.5-86%,

Depending on Oxygenates and Reformulation)

Petroleum Refining to Gasoline (84.5-86%,

Depending on Oxygenates and Reformulation)

K I f Si l ti


16/37

Key Issues for Simulating

Petroleum Fuels

Gasoline sulfur content will be reduced nationwide to 30

ppm beginning in 2004 vs. 150-300 ppm current level

Diesel sulfur content will be reduced to 15 ppm in 2006from the current level of ~300 ppm

In addition, marginal crude has high sulfur content

Desulfurization in petroleum refineries adds stress onrefinery energy use and emissions

Ethanol could replace MTBE as gasoline oxygenate

Energy and emission differences between ethanol and MTBE

Production of gasoline blend stock for ethanol vs. MTBE

P d ti d C i A


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Production and Compression Are

Key Steps for Centralized G.H2 Pathways

NA NG Recovery

(97.5%)

Compressed G.H2 at Refueling Stations

LNG Gasification in

Ports

LNG Production (88.0%)LNG Production (88.0%)

LNG Transport via Ocean Tankers 98.5%)

G.H2 Transport via

Pipelines (96.3%)

nNA NG Recovery (97.5%)WTP Overall Efficiency:

NA NG: 58%

nNA NG: 55%

Steam or

Electricity Export

NA: North American

nNA: non-North American

NG: natural gas

G.H2 Compression at Refueling Stations(89.5% & 95.0% for NG & Electric)

G.H2 Compression at Refueling Stations(89.5% & 95.0% for NG & Electric)

G.H2 Production (71.5%)G.H2 Production (71.5%)

NA NG Processing(97.5%)

nNA NG Processing 97.5%)

NG Transport

via pipelines

H Liquefaction Has Higher


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H2 Liquefaction Has Higher

Energy Losses Than H2 Compression

NA NG Recovery (97.5%)

NA NG Processing (97.5%)

L. H2 at Refueling

Stations

L.H2 Transport via Ocean

Tankers (96.9%)

L.H2 Transport

(98.9%)

nNA NG Recovery (97.5%)

nNA NG Processing (97.5%)

H2 Liquefaction

(71.0%)

H2 Liquefaction

(71.0%)G.H2 production

(71.5%)

G.H2 production

(71.5%)

H2 Liquefaction

(71.0%)

H2 Liquefaction

(71.0%)

G.H2 production

(71.5%)

G.H2 production

(71.5%)

WTP Overall Efficiency:

NA NG: 43%

nNA NG: 42%

R d I f t t I


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Resource and Infrastructure Issues

Result in Many Potential H2 Pathways

Produced from natural gas via steam methane reforming (SMR) now, and in

the foreseeable future

SMR plant emissions need to be taken into account

Regional or station SMR production Could reduce or avoid expensive distribution infrastructure

But production emissions move close to urban areas

Some amount of central SMR CO2 emissions can be potentially sequestered

Energy and emission effects of electrolysis H2 depend on electricity sources

Gasification for H2 production

Coal: CO2 and criteria pollutant emissions, but CO2 can be potentially sequestered

Biomass: criteria pollutant emissions

Nuclear H2 has zero air emissions, but nuclear waste will continue to be an

issue

WTP Energy Losses Could Significantly


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WTP Energy Losses Could Significantly

Affect Efficiencies and GHG Emissions

0%

20%

40%

60%

80%

100%

CompressedNG

CrudeNaphtha

LSDiesel

LSGasoline

Methanol,NG

NGNaphtha

CentralGH2,NG

StationGH2,NG

CentralLH2,NG

CellulosicEthano

l

StationLH2,NG

ElectroGH2,U.S.Mix

ElectroL.H2,U.S.mix

WT

PEnergyEffic

iency

GREET Includes More


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GREET Includes More

Than 50 Vehicle/Fuel Systems

Conventional Spark-Ignition Vehicles Conventional gasoline, federal reformulated

gasoline, California reformulated gasoline

Compressed natural gas, liquefied natural

gas, and liquefied petroleum gas

Methanol and ethanol

Compression-Ignition Direct-InjectionHybrid Electric Vehicles: Grid-Independent

and Connected Conventional diesel, low sulfur diesel, dimethyl

ether, Fischer-Tropsch diesel, and biodiesel

Battery-Powered ElectricVehicles U.S. generation mix

California generation mix

Northeast U.S. generation mix

Fuel Cell Vehicles Gaseous hydrogen, liquid hydrogen, methanol,

federal reformulated gasoline, California

reformulated gasoline, low sulfur diesel,

ethanol, compressed natural gas, liquefied

natural gas, liquefied petroleum gas,

and naphtha

Spark-Ignition Hybrid Electric

Vehicles: Grid-Independent and

Connected Conventional gasoline, federal

reformulated gasoline, California

reformulated gasoline, methanol,and ethanol

Compressed natural gas, liquefied natural

gas, and liquefied petroleum gas

Compression-Ignition

Direct-Injection Vehicles Conventional diesel, low sulfur diesel,

dimethyl ether, Fischer-Tropsch

diesel, and biodieselSpark-Ignition Direct-Injection Vehicles Conventional gasoline, federal reformulated

gasoline, and California reformulated gasoline

Methanol and ethanol

GREET Fuel Economy Ratios of Vehicle


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GREET Fuel Economy Ratios of Vehicle

Technologies (Relative to GVs)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

CNGV LPGV E85 FFV Gasoline

Hybrid

Diesel

Hybrid

Gasoline

FCV

MeOH

FCV

GH2 FCV BP EV

FuelEc

onomyRatio

MIT 2003 GM 2001 MIT 2000

Tailpipe Emissions Will Continue to Decline


23/37

Tailpipe Emissions Will Continue to Decline

Tier 2 Standards (Fully in Effect in 2009, g/mi. for 100K miles)

NMOG CO NOxc

PM HCHO

Bin 10a,b 0.156/0.230 4.2/6.4 0.6 0.08 0.018/0.027

Bin 9a,b 0.090/0.180 4.2 0.3 0.06 0.018

Bin 8a 0.125/0.156 4.2 0.20 0.02 0.018Bin 7 0.090 4.2 0.15 0.02 0.018

Bin 6 0.090 4.2 0.10 0.01 0.018

Bin 5 0.090 4.2 0.07 0.01 0.018Bin 4 0.070 2.1 0.04 0.01 0.011Bin 3 0.055 2.1 0.03 0.01 0.011

Bin 2 0.010 2.1 0.02 0.01 0.004

Bin 1 0.000 0.0 0.00 0.00 0.000a The high values apply to HLDTs. The low values applied to cars and LLDTs.b Bins 10 and 9 will be eliminated at the end of 2006 model year for cars and LLDTs and at the end of 2008 model years for

HLDTs.c Corporate average NOx standard will be 0.07 g/mi. and will be fully in place by 2009.

GREET Takes These Steps to


24/37

GREET Takes These Steps to

Estimate Vehicular Emissions

Emissions of VOC, CO, NOx, CH4, and PM10 Baseline gasoline and diesel vehicles:

HC, CO, NOx and CH4 are estimated with EPAs Mobile model

PM10 is estimated with EPAs Part model

Advanced or alternative-fueled vehicles:

Their emission change rates relative to GVs or DVs are estimated with testing

results or engineering analysis

Their emission levels are calculated with the estimated emission change rates

and baseline GV or DV emissions

SOx emissions for each vehicle type are calculated from sulfur

contained in fuels

CO2

emissions for each vehicle type are estimated from carbon

balance

N2O emissions are based on limited testing results; CARB and EPA

efforts here will greatly reduce tailpipe N2O uncertainties

Per-Mile Total Energy Use of


25/37

0

1,000

2,000

3,000

4,000

5,0006,000

7,000

8,000

9,000

ICEV

:CrudeRF

G

ICEV

:Crude

&NGLP

G

ICEV

:CrudeLS

D

ICEH

EV:C

rudeR

FG

FCV:

Crude

Gaso.

ICEH

EV:C

rudeL

SD

ICEV

:NGF

TD

ICEV:C

NG

ICEH

EV:NGF

TD

FCV:

NGMe

OH

FCV:

NGGH2

ICEF

FV:C

ornE

85

FCV:

Cellulo

sicEtO

H

FCV:

U.S.

kWhG

H2

FCV:

Renew

.KWhG

H2

EV:U

.S.kW

h

Btu/Mile

Per Mile Total Energy Use of

Selected Vehicle/Fuel Systems

Natural gas

feedstockCrude oil

feedstock

Electricity

and EtOH

Per-Mile Fossil Energy Use of


26/37

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

ICEV

:CrudeRF

G

ICEV

:CrudeLS

D

ICEV

:Crude

&NGLP

G

ICEH

EV:C

rudeR

FG

FCV:

Crude

Gaso.

ICEH

EV:C

rudeLS

D

ICEV

:NGF

TD

ICEV

:CN

G

ICEH

EV:NGF

TD

FCV:

NGMeO

H

FCV:

NGGH2

ICEF

FV:C

ornE85

FCV:

Cellulo

sicEtOH

FCV:

U.S.

kWhGH

2

FCV:

Renew

.KWhGH

2

EV:U

.S.kW

h

Btu/Mile

gy


Crude oil

feedstock

Natural gas

feedstock

Electricity

and EtOH

Per-Mile Petroleum Use of


27/37

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

5,000

5,500

ICEV

:Cru

deRF

G

ICEV

:Cru

deLS

D

ICEV

:Cru

de&

NGLP

G

ICE

HEV:

Cru

deRFG

FCV:

Cru

deGaso

.

ICE

HEV:

Cru

deLSD

ICEV

:NGFT

D

ICEV

:CNG

ICE

HEV:

NGF

TD

FCV:

NG

MeOH

FCV:

NGGH

2

ICE

FFV:

Cor

nE8

5

FCV:

Cell

ulos

icEtO

H

FCV:

U.S

.kW

hGH

2

FCV:

Ren

ew.K

WhGH

2

EV:U

.S.kW

h

Btu/Mile


Crude oil

feedstock

Natural gasfeedstock

Electricity

and EtOH

Per-Mile GHG Emissions of


28/37

0

100

200

300

400

500

600

ICEV

:Cru

deRF

G

ICEV

:Cru

deLSD

ICEV

:Cru

de&

NGLP

G

ICE

HEV:

Cru

deRFG

FCV:

Cru

deGaso

.

ICE

HEV:

Cru

deLSD

ICEV

:NGFT

D

ICEV

:CNG

ICE

HEV:

NGFT

D

FCV:

NG

MeOH

FCV:

NGGH

2

ICE

FFV:

Cor

nE8

5

FCV:

Cell

ulos

icEtO

H

FCV:

U.S

.kW

hGH

2

FCV:

Ren

ew.K

WhGH

2

EV:U

.S.kW

h

Grams/Mile


Crude oil

feedstockNatural gas

feedstock

Electricity

and EtOH

Per-Mile Urban In-Use VOC Emissions


29/37

Per Mile Urban In Use VOC Emissions

of Selected Vehicle/Fuel Systems

0.00

0.05

0.10

0.15

0.20

0.25

ICEV:

Crude

RFG

ICEV:

CNG

ICEV:

Crude &

NG LPG

ICE

FFV:

Corn

E85

ICEV:

Crude

LSD

ICEV:

NG FTD

ICE

HEV:

Crude

RFG

ICE

HEV:

Crude

LSD

ICE

HEV:

NG FTD

EV: U.S.

kWh

FCV:

NG GH2

FCV:

NG

MeOH

FCV:

Crude

Gaso.

Grams/Mile

PTW WTP

Per-Mile Urban In-Use NOx Emissions


30/37

of Selected Vehicle/Fuel Systems

0.00

0.02

0.04

0.06

0.08

0.10

0.12

ICEV:

Crude

RFG

ICEV:

CNG

ICEV:

Crude &

NG LPG

ICE

FFV:

Corn

E85

ICEV:

Crude

LSD

ICEV:

NG FTD

ICE

HEV:

Crude

RFG

ICE

HEV:

Crude

LSD

ICE

HEV:

NG FTD

EV: U.S.

kWh

FCV:

NG GH2

FCV:

NG

MeOH

FCV:

Crude

Gaso.

Grams/Mile

PTW WTP

Comparison of Five


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Comparison of Five

Publicly Available WTW Studies

MIT: On the Road in 2020 (2000)

GM, ANL, BP, ExxonMobil, and Shell (2001)

Wang of ANL: Journal of Power Sources (2002)

MIT: Update of the 2000 Study (2003)

Rousseau of ANL: SAE 2003 Congress paper (2003)

Studies available but not included in comparison

ADL study for DOE (2002)

GM European WTW study (2002)

Studies to be available soon

GM, ANL, ChevronTexaco, and Shell (2003)

ANL SUV WTW study (2003)

Comparison of Five Recent


32/37

p

WTW Studies: Energy Use Changes

-60%

-50%

-40%

-30%

-20%

-10%

0%

10%

Diesel

CIDI ICE

Gasoline

SI HEV

Diesel

CIDI HEV

Gasoline

FCV Non-

hybrid

Gasoline

FCV

hybrid

MEOH

FCV non-

hybrid

MEOH

FCV

hybrid

StationcH2 FCV

non-

hybrid

Station

cH2 FCV

hybrid

WTWEnergy

Change

GM 2001 Wang 2002 MIT 2000 MIT 2003 Rousseau 2003

Comparison of Five Recent WTW


33/37

p

Studies: GHG Emission Changes

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

10%

Diesel

CIDI ICE

Gasoline

SI HEV

Diesel

CIDI HEV

Gasoline

FCV Non-

hybrid

Gasoline

FCV

hybrid

MEOH

FCV non-

hybrid

MEOH

FCV

hybrid

StationcH2 FCV

non-

hybrid

Station

cH2 FCV

hybrid

WTWGHGChange

GM 2001 Wang 2002 MIT 2000 MIT 2003 Rousseau 2003

Conclusions


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Conclusions

WTW analysis becomes necessary when comparingvehicle technologies powered by different fuels

Advanced vehicle/fuel technologies could significantly

reduce energy use and GHG emissions

Fuel pathways need to be carefully examined for achieving

intended energy and emission benefits by advanced

vehicle/fuel systems

For criteria pollutants

As vehicle tailpipe emissions continue to decline, WTP emissions could

become a significant share of total WTW emissions

To reduce vehicle-induced WTP emissions, fuel producers will need to be

actively engaged

Limitations of the Current GREET Version


35/37

So far, PM emissions have been measured and regulatedfor PM10. PM2.5 and smaller-size PM are moredamaging; relative differences between PM10 and PM2.5could be very different among vehicle technologies

Black carbon emissions contribution to GHG emissionscould be potentially large

Secondary formation of PM emissions from NOx and SOx

could be important ambient PM emission sources Lack of adequate tailpipe N2O emission measurements

for vehicles powered by different fuels

Fuel consumption and GHG emissions of accessorypower systems such as AC could be significant sources

Outstanding Issues in WTW Analyses

Need to Be Addressed Continuously


36/37

Need to Be Addressed Continuously

Multiple products System expansion vs. allocation (GREET takes both)

System expansion: allocation vs. attribution of effects

Technology advancement over time

Current vs. emerging technologies leveling comparison field

Static snap shot vs. dynamic simulations of evolving technologies

and market penetration over time

Dealing with uncertainties Risk assessment vs. sensitivity analysis

Regional differences, e.g, CA vs. the rest of the U.S.

Trade-offs of impacts

WTW results are better for identifying problems than for

giving the answers

On-Going GREET Efforts


37/37

On Going GREET Efforts

Adding new fuel pathways

Integrating GREET into EPAs MOVES model

Assisting DOE in evaluating its vehicle technology

portfolio

Developing a fully functioning CA version?