How Do Photovoltaic Cells in Solar Panels Produce Electricity

Introduction

Solar panels have become an increasingly popular source of renewable energy. They are made up of photovoltaic cells, which are the essential components responsible for converting sunlight into electricity. But how exactly do these photovoltaic cells work to produce electricity?

Photovoltaic Cell Structure

Layer 1: Absorption

The photovoltaic cell is comprised of multiple layers, with the first layer being an absorber of light. This layer is typically made of silicon, a semiconductor material that releases electrons when struck by photons from sunlight.

Layer 2: Electric Field

Beneath the absorption layer is an electric field that acts as a barrier to prevent the free electrons and holes from recombining. The electric field causes the free electrons to move towards the top of the cell, while the holes move towards the bottom.

Layer 3: Metal Contacts

At the top and bottom of the cell are metal contacts that collect the electrons and holes and transfer them to an external circuit as electricity.

Electricity Generation

Photon Absorption

When sunlight strikes the solar panel, the photons are absorbed by the silicon layer, causing the release of free electrons and generating an electric current.

Electric Field Separation

The electric field within the cell then separates the free electrons and holes, creating a flow of electrons towards the top of the cell and holes towards the bottom.

Electricity Transfer

The metal contacts at the top and bottom of the cell then collect the separated electrons and holes and transfer them to an external circuit, where they can be used as electricity.

Conclusion

In conclusion, photovoltaic cells in solar panels produce electricity through the absorption of sunlight by silicon, the separation of electrons and holes by an electric field, and the transfer of these charged particles to an external circuit. This process allows solar panels to generate clean and renewable electricity from sunlight.