Renewable Energy: Solar Cells and Systems

Photovoltaic Cells

• Convert sunlight into electrical energy through the photovoltaic effect
• Made from semiconducting materials like silicon, which release electrons when exposed to light
• Types:
  • Monocrystalline silicon (most efficient, but expensive)
  • Polycrystalline silicon (less expensive, slightly less efficient)
  • Thin-film solar cells (cheapest, least efficient)

Solar Panel Efficiency

• Measures the percentage of sunlight converted into electrical energy
• Average commercial solar panel efficiency: 15-20%
• Highest efficiency achieved: 26.7% (research setting)
• Factors affecting efficiency:
  • Temperature
  • Shading
  • Angle and orientation of the panel
  • Quality of the panel

Energy Storage

• Necessary to stabilize output and provide power during periods of low sunlight
• Methods:
  • Batteries (lead-acid, lithium-ion, or flow batteries)
  • Other forms of energy storage (pumped hydro, compressed air, flywheels)
• Advantages:
  • Reduces grid dependence
  • Provides backup power during outages
  • Enhances overall system efficiency

Renewable Energy Systems

• Solar panels integrated with other components to generate and distribute electricity
• Components:
  • Inverters (convert DC to AC power)
  • Charge controllers (regulate energy flow to batteries)
  • Mounting systems (fix panels to roofs or ground)
  • Monitoring systems (track performance and identify issues)
• Applications:
  • Residential
  • Commercial
  • Utility-scale power plants
  • Off-grid systems (remote areas, islands, or developing regions)