From Photon to Volt: How Does a Solar Cell Work? - Summary
The core of every photovoltaic system is always the same idea: Light energy is directly converted into electrical energy. This works because special semiconductors like silicon can release electrons when exposed to light.
The Photovoltaic Effect
In the photovoltaic effect, electrons are knocked out of their atom-bound orbits by incoming photons (light particles) under certain material conditions. The P-N junction – a boundary zone between two different semiconductor materials – makes the difference.
From Photon to Voltage: The Process
- Photon hits the junction zone: A light particle reaches the P-N junction
- Electron breaks free: The photon transfers its energy to an electron
- Charge separation: The electric field drives electrons to the N-side and holes to the P-side
- Voltage is created: A usable electrical voltage builds up
- Current flows: When a consumer is connected, electrical current flows
Solar Cell Efficiency
- Monocrystalline modules: 18-24% (highest efficiency)
- Polycrystalline modules: 15-20% (good price-performance ratio)
- Thin-film modules: 8-15% (flexible applications)