Photovoltaics
Technology for the direct conversion of sunlight into electrical power using solar cells made from semiconductor material.
Also known as: PV, Solar Power
What Is Photovoltaics?
Photovoltaics (PV) refers to the direct conversion of sunlight into electrical energy. The name is composed of the Greek word “photos” (light) and “volt” (unit of electrical voltage, after Alessandro Volta). The technology is based on the photoelectric effect in semiconductor materials.
Operating Principle
- Light strikes the solar cell
- Photons release electrons from the semiconductor
- An electric field separates the charge carriers
- Direct current flows, which is converted into alternating current by the inverter
Photovoltaics in Germany
| Metric | Value (2024) |
|---|---|
| Installed capacity | approx. 90 GWp |
| Share of electricity mix | approx. 12% |
| New installations per year | approx. 14 GWp |
| Number of PV systems | over 3.5 million |
| Expansion target 2030 | 215 GWp |
Distinction from Solar Thermal
Photovoltaics generates electricity, solar thermal generates heat. Both technologies use solar energy but differ fundamentally in their operating principle and application.
Practical Tip
A PV system on a residential property is one of the most economical investments in renewable energy. Due to falling module prices and rising electricity costs, the payback period has shortened significantly.
Related Terms
Solar Cell
Semiconductor device that converts sunlight directly into electrical current through the photoelectric effect.
Solar Module
Assembly of multiple solar cells in a weatherproof housing for generating electricity from sunlight.
Solar Thermal
Technology that uses solar heat for hot water preparation and space heating support via solar collectors.
Photoelectric Effect
Physical effect where light photons release electrons from a material -- the fundamental principle behind photovoltaics.
kWp (Kilowatt Peak)
Unit for the maximum power output of a solar module or PV system under Standard Test Conditions (STC).