Stabilization WedgesTackling the Climate Problem with Existing

Technologies

Roberta Hotinski

CLEER UAB Seminar, March 6, 2010

2 2 = 4 billion tons go out

Ocean Land Biosphere (net)

Fossil FuelBurning

+

8

800billion tons carbon

4billion

tons go in

ATMOSPHERE

billion tons added every year

Billions of tons of carbon

“Doubled” CO2

TodayPre-Industrial

Glacial

800

1200

600400

billions of tons carbon

ATMOSPHERE

( ppm)

(570)

(380)

(285)

(190)

Why Wedges?

Predicted global temperature change of 1.4 - 5.8°C by 2100

Graphic courtesy of IPCC

Billions of Tons Carbon Emitted per Year

Historical emissions

0

8

16

1950 2000 2050 2100

Historical Emissions

1.6

Interim Goal

Billions of Tons Carbon Emitted per Year

Current p

ath =

“ram

p”

Historical emissions Flat path

Stabilization Triangle

0

8

16

1950 2000 2050 2100

Today and for the interim goal, global per-capita emissions are ≈ 1 tC/yr.

The Stabilization Triangle

1.6

Billions of Tons Carbon Emitted per Year

Current p

ath =

“ram

p”

Historical emissions Flat path

0

8

16

1950 2000 2050 2100

Today and for the interim goal, global per-capita emissions are ≈ 1 tC/yr.

Stabilization Wedges

16 GtC/y

Eight “wedges”

Goal: In 50 years, sameglobal emissions as today

What is a “Wedge”?What is a “Wedge”?A “wedge” is a strategy to reduce carbon emissions that grows from zero to 1.0 GtC/yr avoided within 50 years

1 GtC/yr

50 years

Total = 25 Gigatons carbon

Cumulatively, a wedge redirects the flow of 25 GtC in its first 50 years.

A “solution” to the CO2 problem should provide at least one wedge.

$100/tC$100/tC

Form of EnergyForm of Energy Equivalent to $100/tCEquivalent to $100/tCNatural gasNatural gas $1.50/1000 scf$1.50/1000 scf

Crude oilCrude oil $12/barrel$12/barrel

CoalCoal $65/U.S. ton$65/U.S. ton

GasolineGasoline 25¢/gallon 25¢/gallon (ethanol subsidy: 51¢/gallon) (ethanol subsidy: 51¢/gallon)

Electricity from coalElectricity from coal 2.2¢/kWh 2.2¢/kWh (wind and nuclear subsidies: 1.9 (wind and nuclear subsidies: 1.9 ¢/kWh)¢/kWh)

Electricity from natural Electricity from natural gasgas

1.0¢/kWh1.0¢/kWh

$100/tC was approximately the EU trading price for carbon $100/tC was approximately the EU trading price for carbon (~$30/ton CO(~$30/ton CO22) in September 2008 (Now ~$18)) in September 2008 (Now ~$18)

A wedge is 2.5 trillion dollars ($100 billion/yr) at $100/tC. A wedge is 2.5 trillion dollars ($100 billion/yr) at $100/tC.

Carbon emission charges in the neighborhood of $100/tC can enable Carbon emission charges in the neighborhood of $100/tC can enable scale-up of most of the wedges. (PV is an exception.)scale-up of most of the wedges. (PV is an exception.)

Energy Efficiency & Conservation

Stabilization Triangle

Renewables & Biostorage

15 Wedge Strategies in 4 Categories

Nuclear Power

2008 2058

TriangleStabilization

Fossil Fuel-Based

Strategies

Use the Wedges Table to compare strategies:

= Electricity Production, =Heating and Direct Fuel Use, =Transportation, = Biostorage

Strategy Sector Description 1 wedge could come from… Cost Challenges

1. Efficiency – Transport

Increase automobile fuel efficiency

(2 billion cars projected in 2050)

… doubling the efficiency of the all world’s cars from 30 to 60

mpg $

Car size & power

2. Conservation - Transport

Reduce miles traveled by passenger and/or freight

vehicles

… cutting miles traveled by all passenger vehicles in half

$ Increased public transport, urban

design

3. Efficiency -Buildings

Increase insulation, furnace

and lighting efficiency

… using best available technology in all new and

existing buildings $

House size, consumer demand

for appliances

4. Efficiency –Electricity

Increase efficiency of power generation

… raising plant efficiency from 40% to 60%

$ Increased plant

costs

5. CCS Electricity

CO2 from fossil fuel power plants captured, then stored

underground (700 large coal plants or 1400

natural gas plants)

… injecting a volume of CO2 every year equal to the volume

of oil extracted $$

Possibility of CO2 leakage

6. CCS Hydrogen

Hydrogen fuel from fossil sources with CCS displaces

hydrocarbon fuels

… producing hydrogen at 10 times the current rate

$$$ New infrastructure needed, hydrogen

safety issues

7. CCS Synfuels Capture and store CO2 emitted

during synfuels production from coal

… using CCS at 180 large synfuels plants

$$ Emissions still only break even with

gasoline

8. Fuel Switching – Electricity

Replacing coal-burning electric plants with natural gas plants

(1400 1 GW coal plants)

… using an amount of natural gas equal to that used for all

purposes today

$

Natural gas availability

9. Nuclear Electricity

Displace coal-burning electric plants with nuclear plants

(2 x current capacity)

… ~3 times the effort France put into expanding nuclear

power in the 1980’s, sustained for 50 years

$$

Weapons proliferation, nuclear

waste, local opposition

10. Wind Electricity

Wind displaces coal-based electricity

(30 x current capacity)

… using area equal to ~3% of U.S. land area for wind farms

$$ Not In My Back Yard

(NIMBY)

11. Solar Electricity

Solar PV displaces coal-based electricity

(700 x current capacity)

.. using the equivalent of a 100 x 200 km PV array

$$$ PV cell materials

12. Wind Hydrogen

Produce hydrogen with wind

electricity

… powering half the world’s cars predicted for 2050 with

hydrogen

$$ NIMBY, Hydrogen

infrastructure, safety

13. Biofuels $$

Double the fuel efficiency of the world’s cars or halve miles traveled

Produce today’s electric capacity with double today’s efficiency

Use best efficiency practices in all residential and commercial buildings

Replacing all the world’s incandescent bulbs with CFL’s would provide 1/4 of one wedge

EfficiencyEfficiency

There are about 600 million cars today, with 2 billion projected for 2055

Average coal plant efficiency is 32% today

Photos courtesy of Ford Motor Co., DOE, EPA

Substitute 1400 natural gas electric plants for an equal number of coal-fired facilities

A wedge requires an amount of natural gas equal to that used for all purposes today

Fuel SwitchingFuel Switching

Photo by J.C. Willett (U.S. Geological Survey).

A wedge worth of natural gas requires about 190 bscfd - U.S. currently imports about 17 bscfd

Implement CCS at

• 800 GW coal electric plants or• 1600 GW natural gas electric

plants or• 180 coal synfuels plants or• 10 times today’s capacity of

hydrogen plants

Graphic courtesy of Alberta Geological Survey

Carbon Capture & StorageCarbon Capture & Storage

There are currently three storage projects that each inject 1 million tons of CO2 per year – by 2055 need 3500.

Requires about 100 times the amount of CO2 currently injected annually for EOR (most in the U.S.)

Triple the world’s nuclear electricity capacity by 2055

Nuclear ElectricityNuclear Electricity

Graphic courtesy of NRC

The rate of installation required for a wedge from electricity is equal to the global rate of nuclear expansion from 1975-1990.

104 of world’s 435 nuclear electric plants are in the United States

Wind ElectricityWind Electricity

Install 1 million 2 MW windmills to replace coal-based electricity,

OR

Use 2 million windmills to produce hydrogen fuel

Photo courtesy of DOE

A wedge worth of wind electricity will require increasing current capacity by a factor of 15

Current U.S. capacity about 35,000 MW

Solar ElectricitySolar Electricity

Photos courtesy of DOE Photovoltaics Program

Install 20,000 square kilometers for dedicated use by 2054

A wedge of solar electricity would mean increasing current capacity 700 times

US PV potential estimated to be ~500 GW

(Navigant Consulting and Clean Power Research, Study for the Energy Foundation)

BiofuelsBiofuels

Photo courtesy of NREL

Using current practices, one wedge requires planting an area the size of India with biofuels crops

Scale up current global ethanol production by 20 times

Need ~1000 billion liters ethanol per year for a wedge – U.S. currently producing ~40 billion liters/yr

Natural SinksNatural Sinks

Photo courtesy of NREL, SUNY Stonybrook, United Nations FAO

Eliminate tropical deforestation

OR

Plant new forests over an area the size of the continental U.S.

OR

Use conservation tillage on all cropland (1600 Mha)

Conservation tillage is currently practiced on less than 10% of global cropland

U.S. forest sequestration potential estimated at 100-200 million tons C/yr

(Birdsey et al.)

Please take a minute and choose 8 wedge Please take a minute and choose 8 wedge strategies you feel are the most promising for strategies you feel are the most promising for

reducing global emissionsreducing global emissions

(can use duplicates)(can use duplicates)

Wedges totals (average of event)

0 2 4 6 8 10 12 14 16

1

Forest/Soil Storage

Biofuels

Wind Hydrogen

Solar

Wind Electricity

Nuclear Electricity

Fuel Switch

CCS Synfuels

CCS Hydrogen

Electric Eff.

Building Eff.

Conservation Transp.

Transport Eff.

CCS Electricity

Take Home MessagesTake Home Messages• To avoid a doubling of To avoid a doubling of

atmospheric COatmospheric CO22, we need to , we need to rapidly deploy low-carbon rapidly deploy low-carbon energy technologies and/or energy technologies and/or enhance natural sinksenhance natural sinks

• We already have an adequate We already have an adequate portfolio of technologies to portfolio of technologies to make large cuts in emissionsmake large cuts in emissions

• No one technology can do the No one technology can do the whole job whole job –– a variety of a variety of strategies will be neededstrategies will be needed

• Every Every ““wedgewedge”” has associated has associated impacts and costs impacts and costs

From McKibben, “Carbon’s New Math,” National Geographic, October 2007

From Socolow & Pacala, “A Plan to Keep Carbon in Check,” Scientific American, Sept. 2006

For more information contactFor more information contact

Roberta HotinskiRoberta Hotinskihotinski@princeton.eduhotinski@princeton.edu