Stabilization Wedges: Mitigation Tools for the Next Half-Century Robert Socolow Princeton University [e-mail] World Bank Washington, DC March 6, 2006 This talk is based on a paper by Stephen Pacala and Robert Socolow, published in the

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Stabilization Wedges Mitigation Tools for the
Next Half-Century Robert SocolowPrinceton
Universitysocolow_at_princeton.eduWorld
BankWashington, DCMarch 6, 2006This talk is
based on a paper by Stephen Pacala and Robert
Socolow, published in the August 13, 2004, issue
of Science, 305 (5686), pp. 968-972, and its
Supporting Online Material, available at
www.princeton.edu/cmi
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What if the fossil fuel future is robust, but the
Greenhouse problem is severe?
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Outline of Talk

• The Wedges Model A simple quantification of
  carbon mitigation as the need for seven wedges
• Some specific wedges
• The challenge of meeting Basic Human Needs is at
  most 0.2 wedges.
• 4. Parting thoughts.

4
Past Emissions
Billion of Tons of Carbon Emitted per Year
14
Historical emissions
7
1.9 ?
0
2105
2055
2005
1955
5
The Stabilization Triangle
Billion of Tons of Carbon Emitted per Year
14
Currently projected path ramp
Stabilization Triangle
Interim Goal
O
Historical emissions
7
Flat path
1.9 ?
0
2105
2055
2005
1955
6
Beat doubling or accept tripling
Billion of Tons of Carbon Emitted per Year
Easier CO2 target
14
850 ppm
Currently projected path ramp
Stabilization Triangle
Interim Goal
O
Historical emissions
7
Flat path
Tougher CO2 target
500 ppm
1.9 ?
0
2105
2055
2005
1955
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The Interim Goal is Within Reach

• Reasons for optimism that global emissions in
  2055 need not exceed todays emissions
• The world today has a terribly inefficient energy
  system.
• Carbon emissions have just begun to be priced.
• Most of the 2055 physical plant is not yet built

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Wedges
Billion of Tons of Carbon Emitted per Year
14
14 GtC/y
Currently projected path
Seven wedges
O
Historical emissions
7 GtC/y
7
Flat path
1.9 ?
0
2105
2055
2005
1955
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What is a Wedge?
A wedge is a strategy to reduce carbon
emissions that grows in 50 years from zero to 1.0
GtC/yr. The strategy has already been
commercialized at scale somewhere.
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Fill the Stabilization Triangle with Seven Wedges
Methane Management
Energy Efficiency
Forests Soils
14 GtC/y
Fuel Displacement by Low-Carbon Electricity
Stabilization
Decarbonized Electricity
Triangle
7 GtC/y
2004
2054
Decarbonized Fuels
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Humanity Already Has The Tools

• READINESS All wedge technologies are already
  deployed somewhere at commercial scale.
• PORTFOLIO No single wedge technology can do the
  whole job, or even half the job.
• CHOICE Not every wedge technology is needed.

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Outline of Talk

• The Wedges Model A simple quantification of
  carbon mitigation as the need for seven wedges
• Some specific wedges
• The challenge of meeting Basic Human Needs is at
  most 0.2 wedges.
• 4. Parting thoughts.

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Allocation of 6.2 GtC/yr
includes coal for heating and cooking
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Efficient Use of Fuel
lifestyle
transport
Effort needed by 2055 for 1 wedge 2 billion cars
at 60 mpg instead of 30 mpg.
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Efficient Use of Electricity
buildings
industry
power
Effort needed by 2055 for 1 wedge . 25 - 50
reduction in expected 2055 electricity use in
commercial and residential buildings
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Wind Electricity
Effort needed by 2055 for 1 wedge One million
2-MW windmills displacing coal power. Today
50,000 MW (1/40)
Prototype of 80 m tall Nordex 2,5 MW wind turbine
located in Grevenbroich, Germany (Danish Wind
Industry Association)
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Effort needed by 2055 for 1 wedge 700 GW (twice
current capacity) displacing coal power.
Nuclear
Electricity
Phase out of nuclear power creates the need for
another half wedge.
Graphic courtesy of NRC
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Power with Carbon Capture and Storage
Effort needed by 2055 for 1 wedge Carbon
capture and storage at 800 GW coal power plants.
Graphics courtesy of DOE Office of Fossil Energy
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IGCC plants are nearly coal CCS plants

• BP will use petcoke and add at Carson refinery,
  California, USA
• CO2 capture CO H2O ? CO2 H2, CO2 - H2
  separation, CO2 absorption
• H2 to turbine for power 3) CO2 pressurization
  and export off site for EOR.

Graphics courtesy of DOE Office of Fossil Energy
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Carbon Storage
Effort needed by 2055 for 1 wedge 3500 Sleipners
_at_1 MtCO2/yr 100 x U.S. CO2 injection rate for
EOR A flow of CO2 into the Earth equal to the
flow of oil out of the Earth today
Sleipner project, offshore Norway
Graphic courtesy of David Hawkins
Graphic courtesy of Statoil ASA
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Already, in the middle of the Sahara!
At In Salah, Algeria, natural gas purification by
CO2 removal plus CO2 pressurization for nearby
injection
Separation at amine contactor towers
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The Future Fossil Fuel Power Plant

• Shown here After 10 years of operation of a 1000
  MW coal plant, 60 Mt (90 Mm3) of CO2 have been
  injected, filling a horizontal area of 40 km2 in
  each of two formations.
• Assumptions
• 10 porosity
• 1/3 of pore space accessed
• 60 m total vertical height for the two
  formations.
• Note Plant is still young.

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Biofuels
Effort needed by 2055 for 1 wedge Two billion 60
mpg cars running on biofuels 250 million hectares
of high-yield crops (one sixth of world cropland)
Usina Santa Elisa mill in Sertaozinho, Brazil
(http//www.nrel.gov/data/pix/searchpix.cgi?getrec
5691971display_typeverbosesearch_reverse1_
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Coal-based Synfuels with CCS Carbon capture
and storage
Effort needed for 1 wedge by 2055 Capture and
storage of the CO2 byproduct at plants producing
25 million barrels per day of coal-based
synfuels Assumption half of C originally in the
coal is captured, half goes into synfuels.
Graphics courtesy of DOE Office of Fossil Energy
Result Coal-based synfuels have no worse CO2
emissions than petroleum fuels, instead of
doubled emissions.
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Possible 14 GtC/y and 7 GtC/y worlds in 2055
Total 14 GtC/y
Total 7 GtC/y
You can play too!
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Summary Whats appealing about stabilization
wedges?

• The stabilization triangle
• Does not concede doubling is inevitable.
• Shortens the time frame to within business
  horizons.
• The wedge
• Decomposes a heroic challenge (the Stabilization
  Triangle) into a limited set of monumental tasks.
• Establishes a unit of action that permits
  quantitative discussion of cost, pace, risk.
• Establishes a unit of action that facilitates
  quantitative comparisons and trade-offs.

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Outline of Talk

• The Wedges Model A simple quantification of
  carbon mitigation as the need for seven wedges
• Some specific wedges
• The challenge of meeting Basic Human Needs is at
  most 0.2 wedges.
• 4. Parting thoughts.

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Basic Human Needs and Fossil Energy
The challenge of meeting Basic Human Needs for
electricity and clean cooking fuels is widely
understood to be political, not technical Power
can be brought to all villages. The indoor air
quality catastrophe related to cooking fuels in
rural and urban areas can be solved with modern
fuels. The diesel fuel for village-scale
engines and the LPG (propane) or DME (dimethyl
ether) fuel for clean cooking can be produced
from biomass, natural gas, crude oil, or coal.
The following four slides explain that meeting
these needs for all humanity has a negligible
effect on global carbon emissions.
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Basic Human Needs and Carbon
Basic Human Need People without access (billions) Sufficiency (per capita-year) Carbon required (GtC/yr)
Electricity 1.6 50W 0.15
Clean cooking fuel 2.6 35 kg propane 0.07
Total 0.22
using global average C-intensity of power in
2002 160 kgC/kWh
current global carbon emissions 7 GtC/yr
Instantly meeting Basic Human Needs for
electricity and clean cooking fuel would produce
only a three percent increase in global CO2
emissions. Including coal and kerosene not
burned, estimates would be still less.
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-0.15 wedges Faster provision of electricity for
1.6 billion people
0.15 GtC/yr
Accelerated Access
3.75 GtC
Business As Usual



2055
2005
2030
1.6 Billion people get access to 600 kWh/yr of
electricity by 2030 in AA, but only by 2055 in
BAU. Electricity is provided at the current world
average carbon intensity 160 gC/kWh. With linear
ramps, AA adds 3.75 GtC of CO2 emissions to the
atmosphere. One stabilization wedge is 25 GtC
of avoided emissions, so following AA instead of
BAU is -0.15 wedges.
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-0.07 wedges Faster provision of clean cooking
fuels for 2.6 billion people
0.07 GtC/yr
Accelerated Access
Business As Usual
1.75 GtC



2055
2005
2030
2.6 Billion people get access to 35 kg/yr of LPG
(propane) or equivalent clean cooking fuel by
2030 in AA, but only by 2055 in BAU. With linear
ramps, AA adds 1.75 GtC of CO2 emissions to the
atmosphere. One stabilization wedge is 25 GtC
of avoided emissions, so following AA instead of
BAU is -0.07 wedges.
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Wedges
projected path
Billion of Tons of Carbon Emitted per Year
14
14 GtC/y
Basic Human Needs for cooking and electricity
Seven wedges
O
Historical emissions
7 GtC/y
7
Flat path
1.9 ?
0
2105
2055
2005
1955
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Problems of Poverty, Problems of Modernity

• Distinguish problems of poverty from problems of
  modernity.
• Problems of poverty are largely a matter of
  political will. They are solved when governments
  are sufficiently motivated to give priority to
  equity and public health.
• Problems of modernity require more than political
  will. Examples are the growing scarcity of
  low-cost hydrocarbons and the build-up of CO2. No
  country can solve such problems on its own.
  Still, there is an immense amount that every
  country can do.
• Both kinds of problems are daunting and urgent.
  But they almost do not overlap.

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Outline of Talk

• The Wedges Model A simple quantification of
  carbon mitigation as the need for seven wedges
• Some specific wedges
• The challenge of meeting Basic Human Needs is at
  most 0.2 wedges.
• 4. Parting thoughts.

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Emission Commitments from Capital Investments
Policy priority Deter investments in new
long-lived high-carbon stock not only new power
plants, but also new buildings. Needed
Commitment accounting.
Credit for comparison David Hawkins, NRDC
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New Coal Build by Decade
Total 1391 GW
Source IEA,WEO 2004 Reference Scenario
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Mitigate in developing countries now!
Some argue that developing countries should not
be burdened with carbon mitigation until
significant steps have been taken in
industrialized countries. This formulation is
seriously misguided. Much of the worlds
construction of long-lived capital stock is in
developing countries. Unless energy efficiency
and carbon efficiency are incorporated into new
buildings and power plants now, wherever they are
built, these facilities will become a liability
when a price is later put on CO2 emissions.
Instead, call for leapfrogging The
introduction of advanced technology in developing
countries first, or at least no later than in
industrialized countries. The world learns
faster, reducing everyones costs. Leapfrogging
is a path to globally coordinated
mitigation. How to compensate those who move
first is a separable challenge.
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Consensus Building via Wedges?

• Advocates of particular wedges agree
• It is already time to act.
• It is too soon to pick winners.
• Subsidy of early stages is often desirable.
• At later stages, markets help to choose the best
  wedges.
• The best wedges for one country may not be the
  best for another.
• The environmental and social costs of scale-up
  need attention.
• Can a consensus for early action be built on
  stabilization wedges?

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National subsidies have elicited wedge
technologies at large scale
Wedges Technology Subsidy
CO2 transport EOR (U.S.)
CO2 geological storage EOR (U.S.), Sleipner (Norway)
Wind Wind electricity (Germany, Denmark, U.K.)
Nuclear power Nuclear power (U.S., Russia, France)
Coal-to-H2 Fertilizer (China)
Biofuels Sugarcane ethanol (Brazil), wood waste (Sweden)
Coal-to-liquids (negative wedges) Synfuels (South Africa)
All of the wedge technologies have already been
commercialized at scale, but generally in only a
few countries. Most subsidies have been motivated
by energy security, not climate. The whole
world has learned from these national
experiences.
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100/tC
Carbon emission charges in the neighborhood of
100/tC can enable scale-up of most of the
wedges. (PV is an exception.)
Form of Energy Equivalent to 100/tC
Natural gas 1.50/1000 scf
Crude oil 12/barrel
Coal 65/U.S. ton
Gasoline 25/gallon (ethanol subsidy 50/gallon)
Electricity from coal 2.2/kWh (wind and nuclear subsidies 1.8 /kWh)
Electricity from natural gas 1.0/kWh
Todays global energy system 700 billion/year (2 of GWP)
100/tC is approximately the EU trading price for
the past six months.
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A world transformed by deliberate attention to
carbon

• A world with the same total CO2 emissions in 2055
  as in 2005 will also have
• Institutions for carbon management that reliably
  communicate the price of carbon.
• If wedges of nuclear power are achieved, strong
  international enforcement mechanisms to control
  nuclear proliferation.
• If wedges of CO2 capture and storage are
  achieved, widespread permitting of geological
  storage.
• If wedges of renewable energy and enhanced
  storage in forests and soils are achieved,
  extensive land reclamation and rural development.
  
• A planetary consciousness.
• Not an unhappy prospect!

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Can We Do It?

• People are becoming increasingly anxious about
  our limited understanding of the experiments we
  are performing on the only Earth we have
• and are learning that there are ways to live
  more cautiously.
• We should anticipate a discontinuity
• What has seemed too hard becomes what simply
  must be done.
• Precedents include abolishing child labor,
  addressing the needs of the disabled, and
  mitigating air pollution.

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Two Messages for the World Bank audience

• Meeting Basic Human Needs has a negligible impact
  on the climate problem
• Mitigation must begin now in developing
  countries.