Sun Power

Class IV

Review of Solar Cooking

Solar Electricity - Photovoltaics I

• Types of solar electricity: Solar Thermal, Photovoltaics, Solar Ponds, Wind Power
• Uses of PV: Homes, the utility grid, Satellites, Billboards, Highway signs, Remote transmitters, pumps, and other equipment, Construction equipment lighting, outdoor lights over doorways and along sidewalks, calculators
• Big picture issues:
  • small amounts of materials, potential, toxicity, recyclability, flexibility
• PV History:
  • Becqueral: 1840 - photoelectric effect
  • Bell Telephone: 1954 - satellites
• Basic types of solar cells: mono/poly crystalline, amorphous (thin film)
• Semiconductor candidates: Germanium, silicon, indium phosphide, gallium aresenide, cadmium telluride, aluminum antimonide, cadmium selenide, gallium phosphide.
• How Solar Cells Work - n-p junctions/separation of charge carriers.
• voltage vs. sunlight characteristic
• Theoretical Efficiencies - Band Gap Theory - < 28% for simple Si cells, ~11-15% for polycrystalline, lower for amorphous cells.
• Books on semiconductor aspects
• Cell design/testing: Sandia/NREL/Australian Institute
• cells/modules/arrays
• Voltage/current/power characteristics
• Temperature derating
• Pay Back Times
• PV Industry
• AC/DC Electricity
• Balance of System: charge controllers, inverters, batteries
  • Costs, lifetimes, failures, etc.
• Dangers: Multiple Energy Sources, etc
• NEC - article 690, Sandia - John Wiles
• Concentrator Systems
• Alternative types of storage
• General Resources