# Solar photovoltaics

Cells that turn sunlight straight into electricity, from rooftops to utility farms.

Source page: https://www.materialinsights.org/energy/e_pv/

Capture · Solar · No. 21

- Capture
- Output: Electricity
 Capture · Solar · Foundation · Energy

Solar modules get about 26.6% cheaper every time world output doubles, and now cost about 10 US cents a watt.

Chart: Illustration: Solar photovoltaics

##### Where it comes from

Chart: Map of where it comes from

Light knocks electrons loose in doped silicon and an internal field drives them out as current; about 706 GWp of modules were made in 2025.

##### Three things to know

1. About 98% of modules made today are crystalline silicon; thin films are a niche and tandems still at pilot stage.
2. A European solar system pays back the energy used to make it in about 0.9-1.1 years.
3. Solar causes about 0.02 deaths per TWh from accidents and pollution, against 24.6 for coal in Europe.

##### The journey

1. 1 **Silicon**Purified and grown into crystals
2. 2 **Wafers**Sliced thin and doped to form a field
3. 3 **Cells**Light frees electrons, silver contacts collect them
4. 4 **Modules**Cells sealed under glass in frames
5. 5 **Inverters**Direct current converted to alternating current
6. 6 **Grid**Rooftops, farms, reservoirs and facades
 Covered in [Energy, power and the units that measure themEnergy](https://www.materialinsights.org/learn/energy/energy-power-units/)[The laws of energy: conservation, entropy and efficiencyEnergy](https://www.materialinsights.org/learn/energy/laws-of-energy/)

##### Go deeper pick a tab to open it in full

## Other sections

- [Overview](https://www.materialinsights.org/energy/e_pv/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_pv/correlation/index.md)
- [Efficiency](https://www.materialinsights.org/energy/e_pv/efficiency/index.md)
- [Techniques](https://www.materialinsights.org/energy/e_pv/techniques/index.md)
- [Resources and labour](https://www.materialinsights.org/energy/e_pv/resources/index.md)
- [Impact on the biosphere](https://www.materialinsights.org/energy/e_pv/biosphere/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_pv/links/index.md)