Power Units: The Terawatt Challenge

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Power Units The Terawatt Challenge

• 103 106 109
  1012
• 1 W 1 kW 1 MW 1 GW 1 TW

Power
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Current Benchmarks

• global energy usage
• 500 Quad (annual total)
• 15 TW (average rate)
• - will double by 2050
• carbon emissions
• 7 Gtons (annual total)
• atmospheric CO2 level
• 350 ppm
• 280 ppm historical background

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Photovoltaic Land Area Requirements
3 TW approx total energy currently used in U.S.
20 TW minimum carbon-free total energy needed
by 2050
3 TW
20 TW
Graphic from Nate Lewis Caltech
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Potential Energy Resources
Fossil fuels with carbon sequestration annual
volume (STP) Lake Superior Nuclear three 1
GW plants every day all year 1 TW Renewables
Geothermal ( 12 TW ) Wind ( 2 - 4 TW
) Hydroelectric ( 0.5 TW ) Solar ( 120,000
TW global average) ( at least 600 TW readily
available)
Basic Research Needs for Solar Energy
Utilization, DOE Report, 2005
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Photosynthesis
( 1961 Nobel Prize )
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Photosynthetic Reaction Center
( 1988 Nobel Prize )
http//www.mpibp-frankfurt.mpg.de/michael.hutter/
rcenter.html
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Artificial Photosynthesis

• Any solar energy conversion method that uses
  some aspects of natures strategy, compounds, or
  both

Strategy Photoinduced electron transfer across a
membrane
Compounds Chlorophyll dyes and electron-transfer
mediators
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Solar Cells
Dye-Sensitized (Grätzel) Cell
Silicon p/n Junction

e-

e-

• light
• absorption
• charge separation
• (holes and electrons)

hn
hn
h
h
o
o
n-Si
p-Si
ETM
HTM
dye
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Polyaniline
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Poly-TAPP

• Oxidative electropolymerization of TAPP is
  expected to occur like aniline polymerization
• Covalent links could include simple amines or
  cyclization to phenazine bridge

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Polymers of TAPP
Poly-TAPP is electrically conductive and has a
fibrous structure with a very high surface area
Poly-TAPP generated without pyridine catalyst has
higher conductivity and a slightly different
morphology