hubbert's peak, the question of coal and climate change

1

Hubbert’s Peak, The Question of Coal, and Climate Change

Dave RutledgeChair, Division of Engineering and Applied Science

Caltech

“There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact.”

Mark TwainLife on the Mississippi

slides (.ppt) and spreadsheets (.xls) at http://rutledge.caltech.edu/

2

The UN Panel on Climate Change

• The UN Intergovernmental Panel on Climate Change publishes assessment reports that reflect the consensus on climate change

• The 4th report is being released this year – Over one thousand authors– Over one thousand reviewers

• Updated measurements show that the temperature is rising 0.013C per year (1956-2005)

3

IPCC Climate-Change Predictions

• Report discusses climate simulations for fossil-fuel carbon-emission scenarios

• There are 40 scenarios, each considered to be equally valid, with story lines and different government policies, population projections, and economic models

4

0

10

20

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1980 2000 2020 2040 2060 2080 2100

Ann

ual F

ossi

l-Fue

l Car

bon

Em

issi

ons,

Gt Carbon Emitted A1 AIM

A1 ASF A1 Image

A1 Message A1 Minicam

A1 Maria A1C AIM

A1C Message A1C Minicam

A1G AIM A1G Message

A1G Minicam A1V1 Minicam

A1V2 Minicam A1T AIM

A1T Message A1T Maria

A2 ASF A2 AIM

A2G Image A2 Message

A2 Minicam A2-A1 Minicam

B1 Image B1 AIM

B1 ASF B1 Message

B1 Maria B1 Minicam

B1T Message B1High Message

B1High Minicam B2 Message

B2 AIM B2 ASF

B2 Image B2 Maria

B2 Minicam B2High Minicam

B2C Maria

B1T Message

A1C AIM

The 40 UN IPCC Scenarios

• Data from the EIA (open symbols, 1980 to 2004)• Emissions have increased 18% since the Kyoto Agreement was negotiated in 1997• Large differences in emissions among scenarios• Oil production in 17 of the scenarios is greater in 2100 than in 2005

5

The Wall Street Journal April 5 Collapse of the World’s Second-Highest Producing Oil Field

World crude-oil production fell in 2006 by roughly the amount of this drop

6

Outline• The 4th UN IPCC Assessment Report• Hubbert’s peak

– The history of US oil production– How much oil do the Saudis have?– The future of world hydrocarbons– The Canadian oil sands

• The coal question– British coal, a nearly complete history– Chinese coal– American coal– The future of world coal, by regions

• Climate change– Simulations of future temperature and sea level– Carbon capture– Wind and sun

• Concluding thoughts

7

King Hubbert

• Geophysicist at the Shell lab in Houston

• In 1956, he presented a paper “Nuclear Energy and Fossil Fuels” at a meeting of the American Petroleum Institute in San Antonio

• He made predictions of the peak year of US oil production based on two estimates of the ultimate production

8

Hubbert’s Peak

• From his 1956 paper• Hubbert drew these by hand, and integrated by counting squares• For the larger estimate, Hubbert predicted a peak in 1970

9

0

1

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3

1900 1920 1940 1960 1980 2000

An

nu

al C

rud

e-O

il P

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ion

, b

illio

ns

of

ba

rre

ls .

What Actually Happened?

• Data from the DOE’s Energy Information Administration (EIA) • Production has dropped 15 years in a row

1970 Hubbert’s PeakAlaskan oil

10

US Crude-Oil Production

• EIA data (1859-2006)• Cumulative normal (lms fit for ultimate of 225Gb, mean of 1975, and sd of 28 years)• Hubbert’s larger ultimate was 200 billion barrels (the Alaska trend is 19 billion barrels)

0

100

200

1900 1950 2000 2050 2100

Cu

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, b

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ns

of

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ls .

29Gb remaining

11

The Largest US Oil Field Prudhoe Bay, Alaska Discovered 1968

12

Prudhoe Bay Oil Production

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200

400

600

0 5 10

Cumulative Production, billions of barrels

An

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, m

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of

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ls .

Trend for ultimate is 12 billion barrels

• FY1977-2006 data from the Alaska Department of Revenue, Tax Division• Initially considered as 8 billion barrels of reserves

13

Estimating Remaining Production from Reserves is Challenging

• Reserves refer to fossil fuels that are appropriate to produce, taking the price into account

• Reserves may be listed conservatively, as for Prudhoe Bay

• Coal reserves have been too high, and they are often not properly distinguished from resources, which are volume estimates for coal seams of a minimum thickness and a maximum depth

• Often reserves are not adjusted for production• New discoveries are important for oil and natural gas• In most countries, the details of oil reserves are

secret, and this means that the published reserves are political statements

14

OPEC Reserves Go Up When the Price Goes Down!

• Data from the 2006 BP Statistical Review• 269Gb rise in reserves, no adjustment for 65Gb produced since 1986

0

50

100

1975 1980 1985 1990 1995 2000 2005

Re

serv

es,

bill

ion

s o

f b

arr

els

.

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Pri

ce,

do

llars

pe

r b

arr

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Iran

Iraq

Kuwait

UAE

Price

15

0

100

200

1975 1980 1985 1990 1995 2000 2005

Res

erve

s, b

illio

ns o

f bar

rels

. Saudi control

264Gb reservesNehring RAND study 176Gb reserves

• Data from the 2006 BP Statistical Review• 95Gb rise in reserves, no adjustment for 53Gb of production since 1988

Saudi Reserves

16

Estimating Remaining Production from a Graph

• In plots of annual production vs cumulative production– We can estimate the remaining production from a trend line– Advantage is that we can identify points on the trend line– Disadvantage is that we cannot make an estimate until the

production drops• Alternative is to plot the growth rate of the cumulative production

(annual production over cumulative production) instead of the annual production – First applied to Daphnia populations in biology in 1963– King Hubbert introduced this approach for estimating remaining oil

production in 1982– Advantage is that we can make an estimate before the peak– Disadvantage is that we need to know the cumulative production

17

0%

5%

10%

0 100 200


Gro

wth

Ra

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or

Cu

mu

lativ

e .

Growth-Rate Plot for US Crude Oil

• EIA data (cumulative from 1859, open symbols 1900-1930, closed symbols 1931-2006)

Trend line is for normal fit (225 billion barrels)

18

0%

5%

10%

0 50 100 150 200


Gro

wth

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or

Cu

mu

lativ

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How Much Oil do the Saudis Have?

• EIA data (open 1975-1990, closed 1991-2006), 1975 cumulative from Richard Nehring• Matt Simmons was the first to call attention to this anomalous situation in his book,

Twilight in the Desert

Trend line is for 1978 RAND study (90Gb remaining)

Official Saudi reserves are 264 billion barrels

19

0%

2%

4%

6%

0 1 2 3

Cumulative Production, trillion barrels of oil equivalent

Gro

wth

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or

Cu

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lativ

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Growth-Rate Plot for World Hydrocarbons

• Oil + natural gas + natural gas liquids like propane and butane• Data 1965, 1972, 1981, 2006 BP Statistical Review (open 1960-1982, closed 1983-2005)• The German resources agency BGR gives hydrocarbon reserves as 2.7Tboe

– Expectation of future discoveries and future OPEC oil reserve reductions– Includes 500Gboe for non-conventional sources like Canadian oil sands

Trend line for 3Tboe remaining

20

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1

2

3

4

1960 1980 2000 2020 2040 2060 2080 2100

Cu

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,Tb

oe

.

World Hydrocarbon Production

• Cumulative normal (ultimate 4.6Tboe, lms fit for mean 2018, sd 35 years)• IPCC scenarios assume that 11 to 15Tboe is available

3Tboe remaining

21

Fort McMurray, Alberta Oil Sands

22

Canadian Oil Sands

• 1.0 Mb per day in 2005, increasing 8% per year• 35Gb reserves for mining (comparable to one year of

world oil production)• 140Gb reserves for wells

– Production with a steam process– Production and upgrading to synthetic crude oil use 25% of the

oil energy equivalent in natural gas– Canadian gas reserves are 10Gboe (end of 2005)– Annual gas production is 12% of reserves per year– Challenges in meeting obligations under the Kyoto agreement

• The Uppsala Hydrocarbon Depletion Group were the first to call attention to these limitations

23






24British Coal

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1850 1900 1950 2000

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British Coal Production

• Data from the US National Bureau of Economic Research (1854-1876), the Durham Coal Mining Museum (1877-1956), and the British Department of Trade and Industry (1957-2006)

• In the peak production year, 1913, there were 3,024 mines

26

0%

2%

4%

0 5 10 15 20 25

Cumulative Production, Gt

Gro

wth

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Growth-Rate Plot for British Coal

• 1854-2006, 1853 cumulative from William Jevons, The Coal Question• Already near the trend line in 1854

27

0.0%

0.1%

0.2%

26.2 26.4 26.6


Gro

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10% per year

Remaining Production for British Coal

• Data from the UK Department of Trade and Industry (1993-2006) • 6 producing underground mines several with less than ten years of coal• 35 strip mines are producing, but there are difficulties in getting permits for new mines

Trend line for 200Mt remaining

28

0

10

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1850 1900 1950 2000

Cu

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Cumulative British Coal Production

• Pre-war lms fit (1854-1945, ultimate 25.6Gt, mean 1920, sd 41 years)• Post-war lms fit (1946-2006, ultimate 27.2Gt, mean 1927, sd 39 years)

Pre-war fit

Post-war fit

29

0

300

600

900

0 50 100Years since Edward Hull's Reserve Survey in 1864

R/P

ra

tio,

yea

rs

Reserves-to-Production Ratio for UK Coal

• 1864 reserves from Edward Hull of the Geological Survey• Other data from the World Energy Council Surveys• Current R/P ratio is 7 years

30

0

1

10

100

1000

1850 1900 1950 2000

Gt

.

Reserves vs Remaining Production

Reserves

Remaining Production

Resources + Reserves

• 1864 reserves from Edward Hull of the Geological Survey• Other data from the World Energy Council Surveys of Energy Resources• Resources include seams of 2ft or more at depths of 4000ft or less

Hull

31

Fraction of Reserves Eventually Produced

• 1864 reserves from Edward Hull of the Geological Survey• Other data from the World Energy Council Surveys of Energy Resources• Will use trends if they exist, reserves otherwise

Hull

0%

20%

40%

1850 1900 1950 2000% o

f R

ese

rve

s E

ven

tua

lly P

rod

uce

d .

Hull

32

Why Are Coal Reserves Too High?

• It seems likely that there are many social, environmental, and technical hindrances that are not fully taken into account in the reserve estimates

• The German Energy Watch Group was early in pointing out that there is a problem with reserves worldwide

• Here are some technical restrictions from the USGS 2000 National Coal Assessment for the Illinois basin

33

Production and Reserves

• 2005 Production numbers from the BP 2006 Statistical Review• Reserves from the World Energy Council surveys of resources (2006/2007

South Africa Yearbook for South Africa, and the Chinese Ministry of Land and Resources 2001 by way of Sandro Schmidt at the BGR)

Production, Gt Reserves, Gt

China 2.38 189

USA 1.05 247

India 0.45 92

Australia 0.37 79

Russia 0.31 157

South Africa 0.26 29

World 6.20 963

34

Chinese Coal

35

0%

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10%

15%

0 10 20 30 40 50


Gro

wth

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lativ

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Growth-Rate Plot for China

• Data from Tim Wright, D.W. Dwyer, and BP 2006 Statistical Review (cumulative from 1896, open symbols 1918-1961, closed symbols 1962-2005), corrections by Jianjun Tu

• Reserves from the Chinese Ministry of Land and Resources 2001 by way of Sandro Schmidt at the BGR

Trend line for 70Gt remaining Reserves are 189Gt

36

0

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100

1950 2000 2050 2100

Cu

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Cumulative Production for China

• Cumulative normal (ultimate 111Gt, lms fit for mean 2015 and sd 27 years)

37

American Coal

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0

500

1,000

1850 1900 1950 2000

An

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t .US Coal Production

• Data from the USGS (Robert Milici)• Will consider the East and the West separately

West of the Mississippi

Total

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60

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1850 1900 1950

An

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Anthracite in Pennsylvania

• Data from the USGS (Robert Milici) • Anthracite is a grade of coal used for home heating that burns with little smoke

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0%

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4%

6%

0 1 2 3 4 5


Gro

wth

Rat

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umul

ativ

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Growth-Rate Plot for PA Anthracite

• Data from the USGS (Robert Milici) cumulative from 1800, symbols 1875-1995• 16% of the 1913 reserves have been produced

41

0

1

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4

5

1850 1900 1950 2000

Cu

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Cumulative PA Anthracite Production

• Normal lms fit for ultimate 5.00Gt, mean 1916, and sd 27 years

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0

20

40

1900 1950 2000

An

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Bituminous Coal in Virginia

• Data from the USGS (Robert Milici) and the EIA• Virginia has coal with high energy content, and much of it is used for metallurgy

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0%

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6%

8%

10%

0 1 2 3


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.Growth-Rate Plot for VA Bituminous

• Data from the USGS (Robert Milici) cumulative from 1800, closed 1900-1940, open 1941-1945, closed 1946-2006, reserves from the EIA

• Trend is for 16% of the 1924 reserves to eventually be produced

Trend is for 800Mt remaining Reserves are 2.8Gt

Pre-war Trend

WWII

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0

1

2

3

1900 1950 2000 2050

Cu

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, G

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Cumulative VA Bituminous Production

• Pre-war normal (ultimate 0.40Gt, lms fit for mean 1926 and sd 16 years)• Post-war normal (ultimate 3.03Gt, lms fit for mean 1984 and sd 34 years)

Pre-war fit

Post-war fit

45

0%

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4%

6%

8%

0 20 40 60


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Coal East of the Mississippi

• Does not include Pennsylvania anthracite• Data from the USGS (Robert Milici) cumulative from 1800, closed 1900-

1940, open 1941-1948, closed 1949-2005, reserves from the EIA

Trend is for 40Gt remaining Reserves are 96Gt

Pre-war Trend

WWII

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0

20

40

1850 1900 1950 2000

Cu

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Cumulative Production for the East

• Does not include Pennsylvania anthracite• Pre-war normal (ultimate 20Gt, lms fit for mean 1924 and sd 20 years)• Post-war normal (ultimate 86Gt, lms fit for mean 1999 and sd 67 years)

Post-war fit

Pre-war fit

47

Western Coal

48

0%

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0 5 10 15


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Coal West of the Mississippi

• Data from the USGS (Robert Milici) closed 1800-1970, open 1971-1978, closed 1979-2005• Reserves from the EIA• Montana is the state with the largest reserves, 68Gt, but annual production is only 36Mt

Trend is for 25Gt remaining Reserves are 79Gt without Montana

Pre-70’s trend

49

0

5

10

15

1900 1950 2000

Cu

mu

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, G

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Cumulative Production for the West

• Pre-70’s normal (ultimate 1.6Gt, lms fit for mean 1929 and sd 23 years)• Post-70’s normal (ultimate 38Gt, lms fit for mean 2016 and sd 25 years)

Pre-70’s fit

Post-70’s fit

50

3%

4%

5%

6%

3 10


Gro

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.

Growth-Rate Plot for Australia and New Zealand

• Data (1981-2005) from the 2006 BP Statistical Review• 1990 Australia cumulative from the History of Coal Mining in Australia, A.J. Hargraves• Reserves from the 2004 World Energy Council survey


51

0%

1%

2%

50 75 100


Gro

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.

Growth-Rate Plot for Europe

• Data (1981-2005) from the 2006 BP Statistical Review• 2005 cumulative from the 2005 BGR Energy Resources Report• Reserves from the 2004 World Energy Council survey, down from

171Gt in 1990


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0%

2%

4%

6%

8%

0 5 10


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..

Growth-Rate Plot for Africa

• Data (open 1981-1990, closed 1991-2005) from the 2006 BP Statistical Review• 2005 cumulative from the 2005 BGR Energy Resources Report• South African reserves were recently reduced by 20Gt (2006/2007 South Africa

Yearbook)


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0%

2%

4%

15 25 35


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. .

Former Soviet Union

• Data from BP (closed 1981-1988, open 1989-2005)• 2005 cumulative from the 2005 BGR Energy Resources Report• Drop that started in 1989 is from the collapse of the Soviet Union• Reserves from World Energy Council surveys, unchanged since the

collapse of the Soviet Union

Trend line for 18Gt remaining 1996 reserves are 157Gt

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0%

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10%

0 5 10 15


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Growth-Rate Plot for South Asia

• Data (1965-2005) from the 2006 BP Statistical Review• Earlier production from World Energy Council Surveys• Reserves from the 2004 World Energy Council survey

Exponential Growth Reserves are 111Gt

55

0%

5%

10%

0.0 0.5 1.0 1.5


Gro

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.

Growth-Rate Plot for Central and South America

• Data (1981-2005) from the 2006 BP Statistical Review• 2005 Cumulative from the BGR Resources Report• Reserves from the 2004 World Energy Council survey

Exponential Growth Reserves are 20Gt

56

Reserves vs Trends for Remaining Production

• North America includes trends for the East (40Gt), the West (25Gt), reserves for Montana (68Gt), and trends for Canada and Mexico (2Gt)

• IPCC scenarios assume 18Tboe is available for production

Region Reserves Gt Trends Gt

North America 255 135

East Asia 190 70

Australia and New Zealand 79 50

Europe 55 23

Africa 30 10

Former Soviet Union 223 18

South Asia 111

Central and South America 20

World (at 3.6boe/t) 963 (3.5Tboe) 437 (1.6Tboe)

57

0

1

2

3

4

1960 1980 2000 2020 2040 2060 2080 2100

Cu

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, T

bo

e .

Future Fossil-Fuels Production

• Hydrocarbons cumulative normal (ultimate 4.6Tboe, lms fit for mean 2018, sd 35 years)• 2005 coal cumulative from the 2005 BGR Energy Resources Report (USGS for US)• Coal cumulative normal (ultimate 2.6Tboe, lms fit for mean 2024, sd 48 years)• The standard deviations of 35 and 48 years can be compared to time constants for

temperature and sea level

1.6Tboe coal remaining

3.0Tboe hydrocarbons

remaining

58






59

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200

400

600

800

1960 1980 2000 2020 2040 2060 2080 2100

Cu

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arb

on

Em

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s, G

t .

Fossil-Fuel Carbon Emissions

• Total fossil-fuel carbon is an input for climate-change models• Carbon coefficients from the EIA: oil (110kg/boe), gas (79kg/boe), coal (141kg/boe),

and future hydrocarbons weighted by BGR reserves (98kg/boe)• The Super-Kyoto Profile is a 50% stretch-out in time with the same ultimate production

520Gt remaining

Producer-Limited Profile

Super-Kyoto Profile

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1,000

2,000

2000 2050 2100Cu

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Gt .

Comparing with the IPCC Scenarios

• Our Producer-Limited profile has lower emissions than any of the 40 IPCC scenarios• Jean Laherrere was the first to point out this anomalous situation

Producer-Limited Profile

61

0

5

10

2000 2100 2200 2300 2400

Year

Fo

ssil-

Fu

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arb

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, G

t

280

330

380

430

Ca

rbo

n-D

ioxi

de

Co

nce

ntr

atio

n,

pp

m .

Producer Limited Carbon

Super Kyoto Carbon

Producer Limited CO2

Super Kyoto CO2

Simulated CO2 Levels

• Predictions using the program MAGICC from Tom Wigley at the National Center for Atmospheric Research in Boulder with a modified WRE profile

• The Producer-Limited Profile gives a peak CO2 concentration of 460ppm in 2070• The Super-Kyoto Profile gives a 440ppm peak

62

0.0

0.4

0.8

2000 2100 2200 2300 2400

Year

Ass

oci

ate

d T

em

pe

ratu

re R

ise

, °C

.

Temperature Rises Associated with Future Fossil-Fuel Use

• Predictions from Tom Wigley’s MAGICC (no mechanical ice model)• The temperature rise is a maximum of 0.8C in 2100• The Super-Kyoto Profile (dashed lines) reduces the maxima by 0.04C• Time constant is of the order of a thousand years (an integrator)• Sensitivity to errors is 0.0012C/Gt carbon

63

CO2 Capture and Storage for Coal Power Plants

• MIT has just completed an outstanding study, The Future of Coal, that gives a cost of $150/t of carbon avoided

• To reduce the temperature in 2100 by 0.001C, the cost would be 100 billion dollars

• Additional cost for transportation and burial– A distribution system is needed that is comparable to our

present natural gas pipeline system– Cannot have leaks on the time scale of a thousand years

64

Wind and Sun

• The time constants of around 50 years for fossil-fuel exhaustion imply that a transition to renewable sources of energy is likely

• Wind is the fastest growing renewable– Current world capacity is 74GW, increasing at 25% per year– 19% of new US capacity last year– Advantage is a production learning curve

• Solar photovoltaics for the home and business– World production in 2006 was 2.2GW, up 33% from 2005– Advantage is that there is no need for new transmission lines– Caltech is installing a 230-kW plant on top of a parking structure

• Concentrating solar– Current capacity is 350MW, built in the 80s in the Mojave Desert– New Nevada Solar One with 64MW near Las Vegas– Advantages are that it uses the direct sunlight available in the Southwest, and

the possibility of thermal storage– The major California utilities, Southern California Edison, San Diego Gas and

Electric, and Pacific Gas and Electric, are each planning to spend a billion dollars on concentrating solar plants

65

Kramer Junction, California

66

• From Schott Glass• Area in red circle in California

could supply sufficient energy to replace the entire US grid

67

Nevada Solar OneJune 2, 2007

68

Concluding Thoughts

• Results– Estimate for future hydrocarbon production (3Tboe) is consistent with

reserves– Estimate for future coal production (1.6Tboe) is about half of reserves– The time constants for fossil-fuel exhaustion are of the order of 50 years– The time constant for temperature is of the order of 1,000 years

• Implications– Since estimate for future fossil-fuel production is less than all 40 UN IPCC

scenarios, producer limitations could provide useful constraints in climate modeling

– A transition to renewable sources of energy is likely– To lessen the effects of climate change associated with future fossil-fuel

use, reducing ultimate production is more important than slowing it down• Opportunities

– One-third of US fossil-fuel reserves are on federal lands, so ultimate production could be reduced substantially by limits on new leases for mining and drilling

– The US has an outstanding resource in its direct sunlight

69

Thanks for Advice, Criticism, Discussion, and Slides

• Tom Wigley and Steve Smith at the National Center for Atmospheric Research in Boulder

• Bill Bridges, Dave Goodstein, Melany Hunt, John Ledyard, Ken Pickar, Tapio Schneider, John Seinfeld, and Tom Tombrello at Caltech

• Dimitri Antsos at the Jet Propulsion Laboratory• John Rutledge at Freese and Nichols, Inc. in Fort Worth• Charlie Kennel at the University of California at San Diego• Sandro Schmidt at the BGR• Juha Karhu at the University of Helsinki

Special thanks to Sandy Garstang in the Caltech Library and Dale Yee in the Caltech Engineering Division for their ingenuity in locating mining records

hubbert's peak, the question of coal and climate change

Documents

gb of production

remaining oil production

scenarios oil production

remaining production

ultimate production

history of us oil production

peak year of us oil

details of oil reserves