Solar Energy and Nanotechnology

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Solar Energy and Nanotechnology
Based on Basic Research Needs for Solar Energy
Utilization

• Report of the Basic Energy Sciences Workshop on
  Solar Energy Utilization

Nathan S. Lewis George L. Argyros Professor of
Chemistry California Institute of Technology with
George Crabtree, Argonne NL Arthur Nozik,
NREL Mike Wasielewski, Northwestern Paul
Alivisatos, UC-Berkeley
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Solar Energy Utilization
500 - 3000 C heat engines electricity
generation process heat
50 - 200 C space, water heating
natural photosynthesis
.001 TW PV 0.30/kWh w/o storage
1.4 TW solar fuel (biomass)
0.002 TW
11 TW fossil fuel (present use)
1.5 TW electricity 0.03-0.06/kWh (fossil)
2 TW space and water heating
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Solar Energy Costs
0.10/Wp
0.20/Wp
0.50/Wp
100
80
60
Efficiency
1.00/Wp
40
20
3.50/Wp
module cost only double for balance of system
200
400
500
100
300
Cost /m2
0.25-0.50/kW-hr
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Solar Energy Conversion
Capture
100 nm-100 µm
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Solar Paint
d
Fooling inexpensive particles into behaving as
single crystals
inexpensive processing, conformal layers
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Interpenetrating Nanostructured Networks
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Ultra-high Efficiency Solar Cells
hot carriers
multiple junctions
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Storage The Need to Produce Fuel
Power Park Concept
Fuel Production
Distribution
Storage
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Solar Thermal Electrolyzer System
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Solar-Powered Catalysts for Fuel Formation
hydrogenase 2H 2e- ? H2
photosystem II
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Solar Land Area Requirements
3 TW
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Control of Materials Properties Through
Nanoscience
biological
physical
mechanical
Self-assembly of complex structures
Hydrogen from water and sunlight
demonstrated efficiencies 10-18 in laboratory
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Nanoscience and Solar Energy
manipulation of photons, electrons, and molecules
artificial photosynthesis
natural photosynthesis
quantum dot solar cells
nanostructured thermoelectrics
theory and modeling multi-node computer
clusters density functional theory 10 000 atom
assemblies
nanoscale architectures top down
lithography bottom up self-assembly multi-scale
integration
characterization scanning probes electrons,
neutrons, x-rays smaller length and time scales
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Basic Research Needs for Solar Energy

• The Sun is a singular solution to our future
  energy needs
• - capacity dwarfs fossil, nuclear, wind . . .
• - sunlight delivers more energy in one hour
• than the earth uses in one year
• - free of greenhouse gases and pollutants
• - secure from geo-political constraints

• Enormous gap between our tiny use
• of solar energy and its immense potential
• - Incremental advances in todays technology
• will not bridge the gap
• - Conceptual breakthroughs are needed that come
  
• only from high risk-high payoff basic research

• Interdisciplinary research is required
• physics, chemistry, biology, materials,
  nanoscience
• Basic and applied science should couple
  seamlessly