CONTENTS

Synopsis: i

Chapters 1: Introduction 1

1. Double the Efficiency, Double the Power, Reduce the Cost
2. The Arguments for Solar Electric Power
3. Overview

Chapter 2: Electric Power Generation and Distribution 8

a. Hubbert’s Peak and Oil & Gas reserves in US

b. Electric Power Production – Oil, Gas, Coal, Nuclear, Hydroelectric

c. Daily and Seasonal Load Profiles and Potential Solar Market Size

d. Distributed Power Reduces Electric Power Grid Vulnerability to Terrorism

e. Cost Targets Today and Tomorrow

Chapter 3: Solar Energy and Solar Cell Efficiencies 17

a. Engineer’s perspective – Power, Intensity, and energy

2. Physicist’ perspective – rainbows, the solar spectrum, cell efficiency, and multicolor solar cells
3. Cell and Module Efficiencies and Power Ratings

Chapter 4: Solar Cells, Single Crystal Semiconductors,

and High Efficiency 25

1. Electrons in atoms as waves and the periodic table of the elements
2. Semiconductors as crystals
3. Junctions and diodes
4. Solar cell band diagrams and power curves
5. High efficiency and multijunction solar cells
6. Types of solar cells and cost trades
7. The importance of single crystals

Chapter 5: The commercial solar cell today 41

1. Silicon single crystal cells down from space
2. The solar cell module
3. Solar cell and module production processes
4. Applications
5. Preview of coming attractions

Chapter 6: Solar concentrators and

high power density solar cells 53

a. Solar photovoltaic (PV) concentrator systems today

b. Durability, performance improvements, and cost

c. Today’s realities and markets and the lower cost 2X mirror module

d. Tomorrow’s lower cost higher efficiency solar concentrators

e. Residential complete energy systems

Chapter 7: The 35% efficient solar cell 64

1. History of multijunction or multicolor solar cells
2. Epitaxy and monolithic multijunction cells
3. New infrared sensitive GaSb cell and the 35% efficient GaAs/GaSb stacked cell
4. Different designs for different applications
5. NREL confirms a 35% efficiency for the InGaP/GaAs/Ge cell

Chapter 8: Infrared solar cells and

combined solar lighting and electricity for buildings 80

a. Concept of concentrated and piped sunlight for indoor illumination

b. Oak Ridge National Lab coalition

c. ORNL Concept and Economic Potential

d. ORNL demonstration prototype

e. Infrared PV array prototype

Chapter 9: ThermoPhotoVoltaic (TPV) Furnace-Generator

for the Home Using Infrared Sensitive PV Cells 88

1. TPV Concept and Midnight Sun™ TPV Heating Stove
2. New Efficient Cylindrical TPV Generator Design and Development
3. Fuel savings, Energy efficiency, and Potential system cost
4. Potential GaSb cell and circuit costs

Chapter 10: Cost of solar electricity today and tomorrow 97

a. Cost of solar electricity today

b. Path from innovation to high-volume commercial production

c. Cost of solar electricity tomorrow

d. The importance of higher efficiency for future cost reduction

Chapter 11: Conclusions –

The investment problem and top down commitment 105

a. Renewable energy can be viable

b. There is an energy problem today

c. Private industry will not and can not do it alone

d. We need top level real commitment

Bibliography 109

Appendix: Key Article Reprints

1. C. A. Campbell and J. H. Laherrere, “The End of Cheap Oil”, Scientific American, March p. 78 (1998).

2. Lewis Fraas and R. C. Knechtli, “Design of High Efficiency Monolithic Stacked Multijunction Solar Cells”, 13^th IEEE Photovoltaic Specialist Conference, p. 886 (1978).

3. Lewis Fraas, James Avery, James Gee, Keith Emery, et. al., “Over 35% Efficient GaAs/GaSb Stacked Concentrator Cell Assemblies for Terrestrial Applications”, 21^st IEEE PV Specialist Conference, p. 190 (1990).

4. R. R. King et al, “Lattice Matched and Metamorphic InGaP/GaInAs/Ge Concentrator Solar Cells” (Independent confirmation of 35% efficient solar cell proposed in 1978), 3^rd World Conference of PV Energy Conversion (2003).