A photovoltaic cell is a device that generates an electric current when exposed to light. The basic principle behind its working is the photovoltaic effect.
Construction
Layers – Conducting material on top surface and backside collects produced electricity. The material on the top doesn’t cover the surface fully to allow penetration of radiation to the depletion region on the p-n semiconductor. The anti-reflection layer traps maximum light rays to be occupied by the p-n semiconductor.
Materials Used : Silicon, Gallium Arsenide, Cadmium Telluride, Gallium Selenide.
Working of Photovoltaic cell
The photoelectric cell is formed of a p-type and an n-type semiconductor. The n-type semiconductor material has electrons as majority carriers and the p-type has holes(positively charged) as majority carriers. When these two are joined, electrons from the n-region migrate to the p-region creating a depletion region between them. When light falls on the depletion region, the energy from photon is transferred to electrons, creating free electron-hole pairs that can move freely and conduct electricity.
Advantages
- Fast response.
- High efficiency.
- Generate voltage without any bias.
Disadvantages
- Powe generation depends on weather conditions.
- Easily damaged.
Applications
- Solar farms.
- Telecommunication and Signalling.
- Standalone systems including solar lamps, parking meters, trash compactors.
Good notes, so helpful
Thank you 🙂