Transcript Document

Alternative Fuels:
Where Are We?
Where Are We Headed?
CalACT 2007 Spring Conference & Expo
April 25, 2007
Paul Griffith
National Projects Manager
ATTI
Presentation Outline
• Energy Basics
• Regulated Emissions and Greenhouse Gases
• Global Warming
• EPA and CARB Regulations
• Bus Fuel Options
• Historical Fuel-Use Trends in Bus Industry
• Comparative Emissions
• Conclusions
Forms of Energy
Kinetic (motion)
– Electrical
– Radiant
• Solar
– Thermal
• Geothermal
– Motion
• Wind
– Sound
Potential (stored)
– Chemical
•
•
•
•
Petroleum
Natural Gas
Propane
Biomass
– biodiesel
– Stored Mechanical
– Nuclear
– Gravitational
• Hydropower
Sources: US Energy Information Administration
Renewables vs. Nonrenewables
6%
94%
(CONSERVATION)
Source: US Energy Information Administration
Secondary Energy Forms
• “Energy Carriers”
• Used to easily store, move, delivery energy
• Electricity
–
–
–
–
–
38% Natural Gas
20% Coal
17% Large Hydro
14% Nuclear
11% Renewable
• Hydrogen
– Natural Gas
– Water
Sources: US Energy Information Administration; CA Energy Commission
US Energy Consumption by Source & Sector
Source: US Energy Information Administration
Dependence on Foreign/
Unstable Sources
Energy Considerations: Availability
Domestic Oil & NG production
past their peak
Domestic Demand
Sources: Assoc. for the Study of Peak Oil and Gas; US Army Corps of Engineers
Non-Renewables: Domestic & World Reserves
300
Domestic Reserves
Years of Reserves
250
200
World Reserves
150
100
50
0
Oil
NG
LNG
Coal
Uranium
Fuel
Source: US Army Corps of Engineers (ERDC/CERL TR-05-21)
Prices
Energy Considerations: Affordability
Domestic & World Demand
Source: US Army Corps of Engineers (ERDC/CERL TR-05-21)
No. 2 Diesel - Average Retail Prices
350
300
200
150
100
U.S.
California
50
Source: U.S. DOE, Energy Information Administration
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
0
1994
Cents per Gallon
250
Natural Gas Prices (Commercial Rate)
18
16
12
10
8
6
4
Residential
2
Commercial
Source: U.S. DOE, Energy Information Administration
2005
2000
1995
1990
1985
0
1980
Price ($/1000 cf)
14
California Average Retail Electricity Prices
16
12
10
8
6
4
Residential
2
Commercial
Industrial
Source: California Energy Commission
2005
2000
1995
1990
1985
0
1980
Cost (cents/kWh)
14
Normalized Price Trends: Diesel, NG, Elect.
Price (Relative to 1994)
2.5
2.0
1.5
1.0
Diesel (US avg)
NG (commercial)
Electricity (commercial)
0.5
Sources: U.S. DOE, Energy Information Administration; California Energy Commission
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
0.0
Projected Price Trends
NON-RENEWABLES
Coal
Fairly Stable
Nuclear
Fairly Stable
LNG
Fairly Stable
Oil
Steady Increases
RENEWABLES
Conservation
Declining
Solar
Declining
Wind
Ethanol
Stable or Declining Stable or Declining
?
Hydroelectric
Stable
Biomass
Stable
H2
Tech. Dependent
ELECTRIC GRID
Slow Increase
Source: US Army Corps of Engineers (ERDC/CERL TR-05-21)
NG
Volatile
Energy Considerations: Security
Combustible fuels
Explosive fuels
create security risks
Nuclear materials
US: 5% of world’s population,
uses 25% annual energy production
-- loss of goodwill
-- context for military conflicts
Source: US DHS; US Army Corps of Engineers
Energy Considerations: Sustainability
Earth’s natural resources depleting at alarming rate
– 100 million years creation = 1-yr world consumption
Global warming
Smog
Acid rain
Ground-level ozone
Fuel mining/production
– destroys ecosystems & biodiversity
Sources: Jellinbah Resources; AP; PDPhoto.org;
US Army Corps of Engineers
Oil
NG
LNG
Coal
Nuclear
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U
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R
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G
N
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Environmental Impacts: Non-Renewables

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









Source: US Army Corps of Engineers (ERDC/CERL TR-05-21)
Ethanol
Biomass
Solar
Wind
Hydroelectric
Geothermal
Conservation
Im
pa
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Environmental Impacts: Renewables

Hydrogen




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
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




Source: US Army Corps of Engineers (ERDC/CERL TR-05-21)
>90% of Californians Breath Unhealthy Air at Times
Source: California Air Resources Board
Criteria Emissions
• Fine Particulate Matter (PM10)
– reduces visibility; penetrates deep into lungs, impairing function
• Carbon Monoxide (CO)
– invisible; reduces oxygen in blood
• Nitrogen Oxides (NOx)
– brownish haze; impair breathing; react in sunlight to form ozone
• Non-Methane Hydrocarbons (NMHC)
– react in sunlight to form ozone
Ground-Level Ozone (O3)
– Invisible; powerful respiratory irritant; damages crops, degrades
rubber & paint
Source: US Environmental Protection Agency
Observed Climate Change
Magnitude, rate and duration of warming in the 20th century is
greater than in any of the previous nine centuries.
The 1990s were the warmest decade in the past 1,000 years.
Simplified Greenhouse Effect




Source: US EPA Climate Change Outreach Kit
Anthropogenic Greenhouse Gases
CA world’s 9th largest emitter
Source: SBAPCD; California Energy Commission
CO2 and Temperature Records
Standard Deviations from Mean
3
Temperature Data CO2 Data Antarctic Ice Core Samples
2.5
2
1.5
1
0.5
0
-0.5
-1
-1.5
-2
800,000 700,000 600,000
500,000
400,000 300,000
200,000
100,000
Years Before Present
Sources: Leland McInnes; NOAA; ORNL
0
Carbon Emissions Since Industrial Revolution
Source: Robert A. Rohde; Emission Database for Global Atmospheric Research
Global Temperature Since Industrial Rev.
20th Century:
Temp +1.1 °F (+0.6 °C)
Source: Robert A. Rohde; Global Warming Art
Top 6 Warmest Years Worldwide Since 1890s
1) 2005
2) 1998
3) 2002
4) 2003
5) 2006
6) 2004
(11 of 12 Warmest Years have Occurred Since 1995)
Source: Goddard Institute for Space Studies (NASA)
Scientific Consensus on Global Warming
1965 Increasing atmospheric CO2 could lead to “marked changes
in climate” by 2000 (Scientific Advisory Board to President
Johnson)
1990 “Observed warming could be largely due to natural climate
variability” (IPCC)
1995 “Evidence suggests a discernable human influence on global
climate” (IPCC)
2001 “New & stronger evidence that most of warming observed
over the last 50 years is attributable to human activities“ (IPCC)
2007 “Global warming very likely manmade” (IPCC)
Sources: Intergovernmental Panel on Climate Change
Glacial Retreat
Length
Collection of
20 glacier
length records
from different
parts of world
1500
2000
Source: World Glacier Monitoring Service
Rhone Glacier, Swiss Alps
1859
2,500-m retreat,
450-m higher
2001
Source: Gary Braasch Photography
Pasterze Glacier, Austria
1875
2,000-m retreat
2004
Source: Univ. Salzburg; Gary Braasch Photography
Portage Glacier, Alaska
1914
Alaska's glaciers receding at
2x rate previously thought
(7-19-02 Science journal)
2004
Source: NOAA; Gary Braasch Photography
Grinnell Glacier, Glacier Nat’l Park, Montana
1911
NPS estimates that all
but a few of the 30
glaciers in this park will
be gone by mid-century
2000
Sources: National Park Service; Gary Braasch Photography
Water Withdrawals from Rivers & Lakes
. . . have doubled
since 1960
Lake Chad
1960
World’s 6th largest lake
1963-2001
Shrunk 95%;
wetlands spoiled
Sources: World Resources Institute;
UNEP (United Nations Environment Programme)
One Planet Many People:
Atlas of our Changing Environment
Amazon River Basin Drought Effects
Source: World Resources Institute
Destabilization of Ocean Currents
25º N lat
Measurements indicate a
30% reduction in ocean
circulation volume
since 1957
Significant climate
changes for areas like
Scandinavia and Britain
that are warmed by the
North Atlantic drift.
Sources: World Resources Institute; Ocean current figure: www.NASA.gov; Transect information: Bryden, Harry L.
et al. "Slowing of the Atlantic meridional overturning circulation at 25° N." Nature 438: 655-657. 1 December 2005
Frequency of Weather Related Disasters
Source: Swiss Re 2005
That’s Where 1°F Gets Us . . .
Where to next?
Climate Model Predictions for Global Warming
SRES A2 Emissions Scenario (assumes no action taken to reduce emissions)
Source: Robert A. Rohde; Global Warming Art
Largest GHG Emitters
(5% of World Population)
Source: World Resources Institute
Think Globally, Act Locally
No Silver Bullet
Photo Credit: 101 In Motion
US Public Transportation Ridership
During First Six Months of 2006:
• ~5 billion passenger trips (+3.2%)
– Light rail +9.4%
– Commuter rail +3.4%
– Bus +3.2%
– Subways +2.6%
– Paratransit +3.8%
– Trolleybus +0.5%
– Other +0.2%
Source: APTA
Energy Policy Act of 1992 (EPAct)
• Mandated alternative fuels as component of
federal, state, and alt fuel provider fleets
• 2004 Final Rule exempts private & local
government fleets
• Although public transit fleets not subject to EPAct,
many have pioneered alt fuel technologies
Source: US Department of Energy
California Urban Bus Emission Standards
Emission Standards (g/bhp-hr)
18.0
Criteria Pollutants
16.0
CO
14.0
12.0
98% Reduction 1988-2010
10.0
8.0
NOx
6.0
4.0
2.0
0.0
HC
PM
1985
NMHC
1990
1995
2000
2005
Source: California Air Resources Board (CCR§1956.1)
2010
Alternative Fuel Options: Mobile Applications
Fuel Characteristics
Transit Bus Manufacturer Comments
Compressed Natural Gas (CNG)
• Works well as a bus fuel, but low energy content,
storage densities, and fuel efficiencies = low range.
• Powers:
> 90% of alt fueled small buses
> 95% of alt fueled mid- to full-size buses
• US produces ~87% of NG it consumes with most of
remainder coming from Canada.
• 2400-3600 psi; onboard cylinders require periodic
inspection and certification.
• Extensive modifications to facilities that fuel, service,
and maintain CNG buses (ventilation and leak detection
& monitoring systems).
• Strong training programs crucial.
Liquefied Natural Gas (LNG)
• Cryogenic liquid fuel: very low temp (-120 to
-260F) & relatively low pressure (< 100 psi).
• Liquefaction process expensive & energy
intensive.
• Less common than CNG
• Similar fuel efficiency, training, facilities
modifications as CNG.
NG Fuels: Bus Manufacturer Comments
• “NG market consistent but not growing”
• “Initially problematic: engine problems, fuel
impurities, and infrastructure costs; those
problems generally resolved”
• “Lingering challenges: reduced range, higher
vehicle weight, fuel availability, and increased
fuel & maintenance costs”
• “LNG has fuel advantages over CNG, but interest
as bus fuel has faded over last 5 years”
• “Concerns about potential liabilities. CNG: high
pressures, potential leaks and fires. LNG:
cryogenic nature, potential to boil off as methane
creates emissions and additional safety concerns”
Source: ATTI Survey of Bus Manufacturers
Liquefied Petroleum Gas (LPG or Propane)
• Used in vehicles since the 1920s.
• Successfully deployed in 30-ft & under bus market.
• ~90% of LPG used in US is domestically produced.
• Range, fuel efficiency, and fueling station cost issues
less challenging than CNG or LNG.
• Heavier-than-air, precautions necessary to avoid
ignition sources in low-lying areas.
Propane: Bus Manufacturer Comments
• “Appropriate for small buses”
• “Higher vehicle cost and fuel availability
limits its application”
• “Safety concerns regarding heavier-than-air
characteristic”
Source: ATTI Survey of Bus Manufacturers
Alcohol-Based Fuels (Ethanol and Methanol)
• Not presently utilized as engine fuels in the bus market
(although some fuel cell demonstrations have used
methanol to produce hydrogen).
• Ethanol
– Previous users report higher costs, premature engine failures
– Industry focusing on lighter-duty engines
• Methanol
– Previous users report engine unreliability and high fuel prices
– Special precautions necessary as flame virtually invisible
Alcohol-Based Fuels: Bus Mfr. Comments
• Ethanol
– increased cost of operation
– option for vans; hybrid cutaway bus in development
• Methanol
– increased cost of operation
– toxic, water-soluble fluid, creating concerns about
groundwater contamination from release during an accident
– corrosive, attacking engine and fuel system components
– although regulated emissions reduced, formaldehyde is
produced
Source: ATTI Survey of Bus Manufacturers
Biodiesel
• Domestically produced, cleaner burning, renewable
fuel derived from vegetable oils or animal fats.
• Usually blended with petro-diesel.
• Becoming increasingly popular since U.S. DOE
ruling in 2001 than EPAct credits apply to blends of
at least 20% (B20).
• Pending: B20 = “CARB Diesel”
• Because blends up to B20 can be used in existing
diesel engines without modifications, it has lowest
capital cost of alt fuels.
Biodiesel: Bus Manufacturer Comments
• “Blends of 10% or less (B5, B10) generally
supported by engine manufacturers; B20
generally not covered under warranty.”
• “Lack of engine warranty in part because
strong specification regulating biodiesel
production has not been adopted by all states.”
Source: ATTI Survey of Bus Manufacturers
Battery-Electric
• Small (22-ft) electric buses successfully
deployed in Santa Barbara CA, Chattanooga
TN, Norfolk VA, and Miami Beach FL; to
date, limited to shuttle operations.
• Quiet, emission-free operation yields
substantial increases in ridership.
• Battery limitations have resulted in low
range, reduced reliability, increased lifecycle costs.
Hydrogen
• Derived from renewable sources or petroleum feedstocks.
• Can be utilized in ICEs and fuel cells.
• Currently plays minimal role in US energy mix; huge potential
• Ford demonstrating V-10, E-450 hydrogen cutaway buses
• Most industry officials believe hydrogen engine and fuel cell
paths at least 10 years away.
• Fuel infrastructure and fuel cell cost greatest challenges.
• Mitigation of hydrogen leaks inside buildings include proper air
ventilation, leak detectors, explosion-proof wiring.
• Safety issues: ability to detonate & to embrittle certain materials.
Hydrogen: Bus Manufacturer Comments
• “When we started fuel cell project we thought
technology 10-12 years out; after delivery to
customer, we believe it more like 15-20 years out”
• “Too expensive, ~$3 million per bus”
• “Costs can come down in volume, but transit
industry does not have necessary volume”
• “More promising platform is automobile, but
volume production won’t happen there before
HUGE investment in refueling infrastructure”
• “Well-to-wheels cost of hydrogen production ~2X to
3X that of petroleum products”
• Hydrogen economy won’t be competitive until
petroleum fuels reach ~$10/gal
Source: ATTI Survey of Bus Manufacturers
Hybrid-Electric
• Substantial attention & development:
– Increased fuel economy (10-50% reported)
– Reduced vehicle emissions
– Reduced operating noise on acceleration
• Thirteen hybrid auto models in commercial production
• ~1,100 hybrid transit buses in regular service in NA
Hybrid-Electric: Bus Manufacturer Comments
• Most benefits, fewest concerns:
–
–
–
–
–
Low regulated emissions
No new emissions
Lower fuel costs partially offset higher acquisition cost
Quieter, smoother operation
Positive perception / public relations reported by customers
• GM Allison developing smaller hybrid drive
• “Plug-in hybrids could result in further improvements
in fossil fuel economies”
Source: Survey of Bus Manufacturers
Bus Manufacturer Survey Summary
• Evaluated CNG, LNG, propane, biodiesel, ethanol,
methanol, hydrogen, electric, and hybrid-electric.
• “Higher costs, reduced performance of alternative fuels
previously justifiable by substantial emissions savings”
• “Emissions differences between ultra-low sulfur diesel
and alt fuels becoming too small to justify the
incremental costs, challenges of alternative fuels”
• “Diesel hybrids achieve comparable emissions with alt
fuels, at lower fuel/maintenance costs”
• “Clear shift away from gaseous fuels toward hybridelectrics; near- to mid-term direction”
Source: Survey of Bus Manufacturers
Alt Fuels vs. 2005 Diesel Heavy-Duty Vehicles
Diesel w/
PM1 Trap
CNG
Propane
Biodiesel
(B20)
BatteryElectric
Emissions
significant
reductions
significant
reductions
until MY10
moderate
reductions
slight
reduction
until MY07
no local
emissions
Domestic
44%
87%
90%
100% (B100)
100%
$2.81/gal
$2.30/DGE3
$2.56/gal
$3.94/DGE
$2.91/gal
$2.92/DGE
16¢/kWh
$1.25/DGE
Life-Cyc Cost
+~3%
+~15%
+~10%
+~7%
+~20%
Power
same
similar
similar
similar
similar
Range
same
slightly
reduced
slightly
reduced
slightly
reduced
reduced
Refueling Infra.
Cost
same
high
moderate
same
moderate
Safety
same
3000 psi;
facility mods.
heavier
than air
same
high voltages
Fuel Price2
1. Particulate Matter
2. Overall average prices, September 2005
3. Diesel Gallon Equivalent
Sources: U.S. Department of Energy; Energy Efficiency & Renewable Energy; SBMTD
Alternative Fueled Buses Under 27.5-ft
2001
2002
2003
2004
CNG (Compressed Natural Gas)
833
700
810
716
LNG (Liquefied Natural Gas)
21
21
21
0
LPG (Liquefied Petroleum Gas, Propane)
55
51
49
35
Battery-Electric
17
13
28
29
E85 (Ethanol)
0
0
0
0
M85 (Methanol)
0
0
0
0
Hydrogen
0
0
0
0
2005 data not yet available
Hybrid-electric buses not considered “alternative fueled” by EPA if input fuel is diesel or gasoline
Source: Energy Information Administration, U.S. Government
Alternative Fueled Buses Over 27.5-ft
2001
CNG (Compressed Natural Gas)
2002
2003
2004
4,710 5,086 5,883 6,240
LNG (Liquefied Natural Gas)
738
947
948
1,012
LPG (Liquefied Petroleum Gas, Propane)
86
101
300
317
Battery-Electric
56
38
11
4
E85 (Ethanol)
0
0
0
0
M85 (Methanol)
11
0
0
0
Hydrogen
0
0
1
1
2005 data not yet available
Hybrid-electric buses not considered “alternative fueled” by EPA if input fuel is diesel or gasoline
Source: Energy Information Administration, U.S. Government
Comparative Emissions
30-ft. Transit Buses
Criteria Emissions
Greenhouse Gas Emissions
2006 Comparative Emissions: Diesel vs. CNG
Certified Emissions for 2006 230-hp Cummins ISB/BG 230
NOx
1
NMHC PM10
CO
LS Diesel1 (g/bhp-hr)
2.03
0.08
0.10
1.3
CNG (g/bhp-hr)
1.43
0.00
0.00
1.0
Tested with Low-Sulfur Diesel (500 ppm). Ultra-Low Sulfur Diesel (15 ppm) reduces
emissions of sulfur compounds enabling NOx, HC, and PM reductions.
2007 & 2010 Regulations
NOx
2007 (g/bhp-hr)
2010 (g/bhp-hr)
1.2
0.2
NMHC PM10
0.14
0.14
0.01
0.01
Sources: Cummins; CARB; US EPA
CO
1.3
1.3
30-ft Diesel & CNG Bus Emissions
Emissions (g/mi) = Emission Rate x
Fuel Density
Brake Spec. Fuel Consumption x Fuel Efficiency
where:
Fuel Density = 7.16 lb/gal diesel
Brake Specific Fuel Consumption = 0.4 lb/bhp-hr diesel
Fuel Efficiency = 5.02 mpg diesel (2004 Gillig LF 30)
LS Diesel (g/mi)
CNG (g/mi)
2007-09 (g/mi)
2010 (g/mi)
NOx
7.2
4.9
NMHC
0.29
0.00
PM10
0.36
0.00
CO
4.6
3.4
4.3
0.7
0.50
0.50
0.04
0.04
4.6
4.6
Sources: Cummins; CARB; US EPA
Relative to LSD
Biodiesel Emissions
Negligible criteria emissions benefits when blended with ULSD
Sources: US EPA; California Energy Commission, Consumer Energy Center
30-ft Electric Bus Emissions
U.S. Marginal Off-Peak Power Generation Emissions
NOx
NMOG
PM10
CO
g/kWh
0.073
0.025
?
?
Emissions (g/mi) = Emission Rate x AC Energy Consumption Rate
where: AC Energy Consumption Rate (30-ft EB) = 1.56 AC kWh/mi
g/mi
NOx
NMOG
PM10
CO
0.11
0.039
?
?
Source: Electric Power Research Institute; SBMTD
2006 30-ft Bus Emissions (Normalized)
100%
NOx
NMHC
Emissions
80%
PM10
60%
CO
40%
20%
??
0%
LS
Diesel
MY2007
MY2010
ULSD or
B20
Hybrid
(B20 or
ULSD)
CNG
Electric
Local
Sources: Cummins; CARB; US EPA; EPRI; SBMTD
Electric
Total
Well-to-Wheels Emissions
Source: California Energy Commission
GHG Emissions: CO2
Transit Buses
1800
Combustion
Fuel Production
1600
1400
1000
800
600
400
200
Propane
CNG/LNG
Hybrid
(B20)
Hybrid
B20
0
Diesel
g/km
1200
Source: CSIRO (Life-Cycle Emissions Analysis of Alternative Fuels for Heavy Vehicles)
GHG Emissions: CH4
Transit Buses
3.0
Combustion
Fuel Production
2.5
1.5
1.0
0.5
Propane
CNG/LNG
Hybrid
(B20)
Hybrid
B20
0.0
Diesel
g/km
2.0
Source: CSIRO (Life-Cycle Emissions Analysis of Alternative Fuels for Heavy Vehicles)
GHG Emissions: N2O
Transit Buses
0.14
Combustion
Fuel Production
0.12
0.08
0.06
0.04
0.02
Propane
CNG/LNG
Hybrid
(B20)
Hybrid
B20
0.00
Diesel
g/km
0.10
Source: CSIRO (Life-Cycle Emissions Analysis of Alternative Fuels for Heavy Vehicles)
Global Warming Potential of GHGs
Greenhouse Gas
% of
Total
Global Warming
Potential (100-yr)
Carbon Dioxide (CO2)
72%
1
Methane (CH4)
18%
23
Nitrous Oxide (N2O)
9%
296
Hydrofluorocarbons (HFCs)
1%
4,600- 14,000
Sources: Emission Database for Global Atmospheric Research;
Intergovernmental Panel on Climate Change (3rd Assessment Report, 2001)
Total GHGs: Weighted by 100-yr GWP
GWP Wtd. Combustion
1800
1600
GWP Wtd. Fuel Production
1400
1200
1000
800
600
400
200
Propane
CNG/LNG
Hybrid
(B20)
Hybrid
B20
0
Diesel
g/km CO2-equivalents
Transit Buses
Source: CSIRO (Life-Cycle Emissions Analysis of Alternative Fuels for Heavy Vehicles)
Summary & Conclusions
• CNG has dominated the alt fuels bus market
• Emissions gap between diesel & alt fuels narrowing
– 2010 regulations: diesel emissions comparable with alt fuels
• Biodiesel
– lowest capital cost of alt fuels
– Renewable, energy security, reduced GHG emissions
• Bus industry moving towards diesel hybrids
– improved fuel economy, reduced emissions
• Electric Buses
– lowest emissions