Transcript Carbon Storage Mitigating Climate Change?

Carbon Storage Mitigating
Climate Change?
Will this work? Is it too late?
Carbon Retention Timescale is
Long
Lag Time Issue
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Is really quite serious
We don’t even know yet of the climate
system is responding to increased CO2
Other factors (water vapor feedback loop,
aerosol suppression, increased clouds)
may be at work
If the lag time (some times called the
warming pipeline) is large then
stabilization targets may be coming too
late
The Physics of the Problem
CO2 long atmospheric lifetime
 Ocean (water) takes a long time to heat
up and cool off  ocean SST is primary
driver of global climate change.
 Estimates suggest warming pipeline is
0.5 – 1 degree C (and there is nothing
we can do about this)
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Probability and Concerns
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A recent, thorough analysis has yielded this
thoroughly discouraging result:
Complications
Aerosols/global dimming may well be
masking the warming signal  this is an
area of much current research
 Feedback from clouds looks likely to be
positive rather than negative in the most
recent grid models that actually contain
clouds
 This means the 2 degree C stabilization
target has already been exceeded
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Global Carbon Emissions
The Stabilization Triangle
Wedges:
Carbon Budget: Know THIS!
Carbon Accounting I
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1 ppm CO2 = 2.1 GigaTons of C
Averaged over last 10 years net increase
has been 1.8 ppm or 3.8 GTC annually
Sources = 7.7 (fossil) + 1.4 (deforest) = 9.1
Sinks = 3.0 (forests) + 2.3 = 5.3
9.1 -5.3 = 3.8
Carbon Accounting II
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Current rate (2008-2010) = 2.5 ppm so we are
rapidly exceeding the Sinks.
Make simple model – Assume sinks remain
constant at 5.3 GTC removal.
Can then roughly figure out stabilization levels for
emission targets.
Very likely nothing can be done about the 1.4
GTC from deforestation so concentrate on the
fossil fuel issue
Carbon Accounting III
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Cut emissions by 25% = 5.7
Emissions still rise by (5.7+1.4 - 5.3)/2.1 = 0.85
ppm per year  still that’s much less than the
current rate of 2.5 ppm!
Cut emissions by 50% = (3.85+1.4 - 5.3) =5.25
and now your in equilibrium
Cut emissions by 75% =(1.9+1.4 -5.3) and you
get only 1 ppm reduction per year
Do this today at you get to 350 ppm in 40 years.
Continue BAU for 10 more yearsCarbon Intensity @1% per year
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Reach 430 ppm of CO2
Net annual C increase is now 5.8 GTC
Fossil source function is now 8.7 GTC
50% reduction then = (4.35+1.4-5.3) = 0.45/2.1 =
0.2 ppm increase
75% reduction then = (2.18+1.4-5.3)=-0.8 ppm
per year so now it takes 100 years to reach 350
ppm!  This should set policy framework!
Avoiding The 500 PPM Level
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Our current annual emission is 7 GTC! BAU trajectory
is 500 ppm by 2050 or adding 175 GT over next 50
years above current baseline. Must therefore suppress
3.5 GT year (which is 50% of the current rate)
Look for somewhat equal contributions in all areas (e.g.
storage, production, fuel, etc)  Wedge steps to get
there by 2055
Each Wedge requires a large scale, multi-national effort!
Wedges correspond to worldwide emissions – each
country’s contribution varies; US will have to reduce or
sequester about 80% of its current carbon emission to
play fair
Energy Efficiency and Conversion
Strategies
• Increase fuel economy for 2 billion cars
from 30 to 60 mpg
• or, decrease annual miles for 2 billion 30
mpg cars from 10,000 to 5000
• Efficient buildings: cut carbon emissions in
buildings by 25%
• Increase coal fired electricity efficiency
from 40% to 60% using advanced high
temperature materials
New Fuel Sources Strategies
• Replace 1400 GW of 50% efficient coal
fired plants with natural gas fired plants
• Increase ethanol production by a factor of
100 relative to current US production
utilizing 1/6 of world available cropland
• Add 4 million 1 MW peak windmills (100
times current world capacity) for Hydrogen
production for fuel cells
CCS Strategies
• Capture at baseload power plant (at 800
GW Coal or 1600 GW of Natural Gas)
• Capture at steam-reforming Hydrogen
production plants at levels of 250 Mt/year
for gas and 500 Mt/year H-production by
coal
• Capture at coal-liquid plants  crucial;
future facilities could produce 30 million
barrels a day
Alternative Energy Strategies @
2TW Electricity Production
• Need more due to lower capacity factor of
Alternatives (30-40%) compared to Fossil
or Nuke plants (90%).
• Substitute wind power for Coal power at
the scale of building 400,000 5 MW
turbines on land or offshore
• Substitute PV power for Coal power at the
level of 2000 GW  North African Desert
Wedge Approach – 1GTC/yr
reduction by 2054
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Wedge achieved by US if it
reduces its carbon intensity 2.1% per
year for next 50 years
 2 billion cars have large lever arm on
the wedge
 In 2000, Coal power plants operated
at 32% efficiency and produced ¼ of
all carbon emissions (1.7 GTC)  a
wedge is achieved at 60% efficiency
Wedge Approach Continued
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One wedge achieved by displacing 1400 GW of
coal with gas by 2054. Requires China/Russia
agreement on Natural Gas.
Substitute 700 GW of Nuclear fission for Coal
would achieve a wedge  requires restoration of
public confidence in safety and waste disposal
Wedge achieved by implementation of any 2 TW
AE scheme for electricity production
34 million gallons per day of ethanol production
achieves a wedge (this is 60 times larger than
current world production rate!)
Summary of Wedge portfolio