The Wedge Game

1
The Wedge Game

• Developed by
• Rob Socolow and Steve Pacala
• Carbon Mitigation Initiative
• Princeton University
• www.princeton.edu/cmi

2
Historical emissions profile
Science, Vol 305, Issue 5686, 968-972, 13 Aug.
2004 Scientific American, Special Issue,pp.
50-57, Sept. 2006
3
The stabilization triangle
Billions of Tonnes of Carbon Emitted per Year
14
Currently projected path
Stabilization Triangle
Interim Goal 500 - 550ppm in 50 years. Steep
decline beyond
Flat path
O
Historical emissions
7
0
2105
2055
2005
1955
4
Wedges
7 BtC/y
5
What is a wedge?
An activity that reduces emissions to the
atmosphere that starts at zero today and
increases linearly until it accounts for 1 BtC/yr
of reduced carbon emissions in 2055

1 BtC/yr
Total 25B tonnes of carbon
50 years
6
What are the options?
Nuclear Fission
CO2 Capture and Storage
14 BtC/y
Fuel Switching
Energy Efficiency and Conservation
Stabilization
Forests Soils
Triangle
7 BtC/y
2005
2055
Renewable Electricity and Fuels