Stone to Silicon

Energy · 1839

Photovoltaic effect

Light falling on an electrode in electrolyte makes a current.

Nineteen-year-old Edmond Becquerel observed the effect in his father's lab in 1839. It lay mostly dormant until quantum theory explained it, but it is the physical basis of every solar panel.

See it in the living treeWikipedia

Arcs above join it to what it stood on, arcs below to what it led to. The bar places this stretch on the tree's whole timeline.

What it built on 1

What it led to 1

Related measurements

The dashed line marks when it first worked.

Solar PV module price Latest: 0.12 $/W (2025 USD) (2025) Source: Our World in Data

Installed solar capacity Latest: 2.4k GW (2025) Source: Our World in Data