Temperature anomalies relative to 20th Century Average
Approximate pre-industrial temperature anomaly (~ -0.2°C)
Approximate late 20th century temperature anomaly (~ 0.3°C)
Net temperature anomaly – late 19th century to late 20th century ~0.5°C
http://www.ncdc.noaa.gov/cmb-faq/anomalies.php
Climate Change Mitigation
Fossil Fuel
Burning
8
billion
tons go in
4
billion tons added every
year
800
billion tons carbon
Ocean
Land Biosphere (net)
2
+
2
=
4
billion tons go out
Read:
NYS Interim Climate Action plan – executive Summary http://www.nyclimatechange.us/ewebeditpro/items/O109F24046.pdf
Stabilization Wedges - Science, Vol 305, Issue 5686, 968-972, 13 Aug. 2004 (on moodle)
Science, Vol 305, Issue 5686,
968-972, 13 Aug. 2004
Historical emissions profile
Scientific American, Special Issue,
pp. 50-57, Sept. 2006
Billion of Tonnes of
Carbon Emitted per
Year
14
Business as usual –
continue at current rate
of emission growth
(>800 ppm, +5°C)
Hold current emissions
(2007) –
(525 ppm, +3°C)
Historical
emissions
7
Cut 2007 emissions in
half over 50 years–
(450 ppm, +2°C)
1.9 
0
1955
2005
2055
2105
The stabilization triangle
Billion of Tonnes of
Carbon Emitted per
Year
16
Stabilization
Triangle
Flat path
8
Historical
emissions
O
Interim Goal
500 - 550ppm in 50
years. Steep decline
beyond
0
1955
2007
2057
2105
Assumed 2057
carbon emission
sources
Concept of Mitigation Wedges
16
Billion of Tonnes of
Carbon Emitted per
Year
16 BtC/y
Eight “wedges”
8
Historical
emissions
Flat path
O
8 BtC/y
4 additional wedges needed
to cut emissions by 50% by
2057
0
1955
2007
2057
2105
What is a wedge?
An activity that reduces emissions to the atmosphere that starts at zero
in 2007 and increases linearly until it accounts for 1 BtC/yr of reduced
carbon emissions in 2057
1 BtC/yr
Total = 25B tonnes of carbon
50 years
Cumulatively, a wedge redirects the flow of 25 GtC in its first 50 years.
This is 2.5 trillion dollars at $100/tC.
A “solution” to the CO2 problem should provide at least one wedge.
What are the options?
Nuclear Fission
CO2 Capture
and Storage
16 BtC/y
Stabilization
Triangle
Forests & Soils
2007
Fuel Switching
Energy Efficiency and
Conservation
8 BtC/y
2057
Renewable Electricity
and Fuels
Photos courtesy of Ford Motor Co., DOE, EPA
Efficiency
Example –
1 wedge
Double the fuel efficiency of the world’s
cars or halve miles traveled
Produce today’s electric capacity with
double today’s efficiency
Average coal plant efficiency is 32% today
There are about
600 million cars
today, with 2 billion
projected for 2055
Use best efficiency practices in all
residential and commercial buildings
E, T, H / $
Sector s affected:
E = Electricity, T =Transport, H = Heat
Cost based on scale of $ to $$$
Replacing all the world’s incandescent bulbs
with CFL’s would provide 1/4 of one wedge
Fuel Switching
Substitute 1400 natural gas electric
plants for an equal number of coalfired facilities
E, H / $
Photo by J.C. Willett (U.S. Geological Survey).
A wedge requires an amount of
natural gas equal to that used for
all purposes today
Carbon Capture & Storage
Implement CCS at
• 800 GW coal electric plants or
• 1600 GW natural gas electric
plants or
• 180 coal synfuels plants or
• 10 times today’s capacity of
hydrogen plants
Graphic courtesy of Alberta Geological Survey
E, T, H / $$
There are currently three storage
projects that each inject 1 million tons
of CO2 per year – by 2055 need 3500.
Nuclear
Electricity
Triple the world’s nuclear
electricity capacity by 2055
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.
E/ $$
Wind Electricity
Install 1 million 2 MW windmills to
replace coal-based electricity,
OR
Use 2 million windmills to produce
hydrogen fuel
Photo courtesy of DOE
E, T, H / $-$$
A wedge worth of wind electricity will require
increasing current capacity by a factor of 30
Solar Electricity
Install 20,000 square kilometers
for dedicated use by 2054
Photos courtesy of DOE Photovoltaics Program
A wedge of solar electricity would mean increasing current
capacity 700 times
E / $$$
Biofuels
Scale up current global ethanol
production by 30 times
Photo courtesy of NREL
Using current practices, one wedge requires planting
an area the size of India with biofuels crops
T, H / $$
Natural Sinks
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)
B/$
Conservation tillage is currently
practiced on less than 10% of
global cropland
Photos courtesy of NREL, SUNY Stonybrook, United Nations FAO
Wedges Available
Choosing Appropriate Wedges
• Review Strategies available (next two slides)
• You may use a strategy more than once
• Use only whole numbers of wedges
• You may use a maximum of
– 6 electricity wedges (E)
– 5 transportation wedges(T)
– 5 heat or direct fuel use wedges (H)
• Cost and impacts must be considered. Each wedge should
be viewed in terms of both technical and political viability.
• See video - http://www.youtube.com/watch?v=-wcDHZ7Z-hQ
NYS Plans
• Gov. Paterson Executive Order 24 (Aug. 2009)
(http://www.state.ny.us/governor/executive_orders/exeorders/eo_24.html )
– Reduce emissions of heat-trapping greenhouse gases by 80 percent from 1990
levels, by the year 2050 ("80 by 50“)
– Improve resilience to climate change in all the state's communities
http://www.dec.ny.gov/energy/44992.html
– Establish NYS Climate Action Council http://www.nyclimatechange.us/index.cfm
– Develop NYS Climate Action plan (Jan. 2010)
• Renewable Portfolio Standard December 2009, (30 x 15)
– proportion of renewable electricity consumed in NYS to 30 percent by 2015
• NYSDEC – Climate Smart Communities (http://www.dec.ny.gov/energy/50845.html )
• Part of RGGI –
– a ten-state cooperative - reduce GHG emissions from electric power plants
– cap and trade system.
– first market-based, mandatory program in the nation.
http://www.dec.ny.gov/energy/rggi.html
NYS - Basic strategies for reducing
emissions
• 80x50 emissions target of 50 MMT CO2e
• Constraint: Cutting GHG emissions could have real-world
consequences if low-carbon or no-carbon energy sources
don’t adequately replace fossil sources.
• four key strategies to reduce GHG emissions:
– energy conservation through demand reduction and energy efficiency.
– Increased reliance on local, point-of-use renewable energy
technologies such as solar is the second strategy.
– Reducing combustion of fossil fuels ( 87% of current GHG emissions)
– fuel switching where combustion must still be used
• Three Scenarios
NYS Vision of 2050
Sector
Transporta
tion
Light Duty
Vehicles (cars)
High Duty
Vehicles
(trucks)
Electricity
Efficiency
Electricity
Generation
http://www.nyclimatechange.us/ewebeditpro/items/O109F22816.pdf
http://www.nyclimatechange.us/InterimReport.cfm
Yellow
~51.3 MMT CO2e
Deep Blue
~15 MMT CO2e
Ultraviolet
~20 MMT CO2e
Smart growth VMT ↓ 10%
CV reaches 37 mpg; (30%)
HEV miles at 50mpg (30%)
PHEV (40%)
50% trucks switch to rail
Smart growth – VMT ↓ 40%
100% FCV @65 mpg equiv.
(hydrogen (nuclear-based))
Smart growth -VMT ↓40%
EV: 95%
Others: 50 mpg - E85/BD
50% trucks switch to rail;
40% of balance - biodiesel
50% trucks switch to rail
~21 MMT CO2e
25% improvement
*Residential
* Commercial
10% - Industrial
Minimize combustion;
remaining switches to
IGCC, NGCC w/ CCS
Max hydro, wind
No new nuclear
~13 MMT CO2e
~10 MMT CO2e
efficiency gains as in Yellow efficiency gains as in Yellow
115 MMT CO2 eq/y
Maximize hydro
2 new nuclear plants
30% from renewables
(utility-scale solar, wind)
40% NGCC and CCS
<50 MMT CO2 eq/y
Maximize hydro
Max wind
15 new nuclear plants
35% from renewables
(utility scale solar, wind)
17% from NGCC and CCS
35%-40% residential from
local solar
<50 MMT CO2 eq/y
Take Home Messages
• In order to avoid a doubling of atmospheric CO2, we need to
rapidly deploy low-carbon energy technologies and/or
enhance natural sinks
• We already have an adequate portfolio of technologies to
make large cuts in emissions
• No one technology can do the whole job – a variety of
strategies will need to be used to stay on a path that avoids a
CO2 doubling
• Every “wedge” has associated impacts and costs
EFFICIENCY AND CONSERVATION
• Improve fuel economy of the two billion cars
expected on the road by 2057 to 60 mpg from
30 mpg.
• Reduce miles traveled annually per car from
10,000 to 5,000.
• Increase efficiency in heating, cooling, lighting,
and appliances by 25 percent.
• Improve coal-fired power plant efficiency to
60 percent from 40percent.
http://ngm.nationalgeographic.com/2007/10/carbon-crisis/img/stabilization_wedges.pdf
CARBON CAPTURE AND STORAGE
• Introduce systems to capture CO2 and store it
underground at 800 large coal-fired plants or
1,600 natural-gas-fired plants.
• Use capture systems at coal derived hydrogen
plants producing fuel for a billion cars.
• Use capture systems in coal derived synthetic
fuel plants producing 30 million barrels a day.
Use only LOW-CARBON FUELS
• Replace 1,400 large coal-fired power plants
with natural-gas-fired plants.
• Displace coal by increasing production of
nuclear power to three times today’s capacity.
RENEWABLES AND BIOSTORAGE
• Increase wind-generated power to 25 times current
capacity.
• Increase solar power to 700 times current capacity.
• Increase wind power to 50 times current capacity to
make hydrogen for fuel-cell cars.
• Increase ethanol biofuel production to 50 times current
capacity. About one-sixth of the world’s cropland
would be needed.
• Stop all deforestation.
• Expand conservation tillage to all cropland (normal
plowing releases carbon by speeding decomposition of
organic matter).