Energy · 1866
Self-excited dynamo
A generator that powers its own magnets turns mechanical work into electricity at scale.
In 1866 to 1867 Werner von Siemens, Charles Wheatstone and others showed the dynamo principle, using the machine's own output to energize its field magnets. It made electricity cheap enough for lighting and industry, ending dependence on batteries.
What it built on 2
What it led to 8
Related measurements
The dashed line marks when it first worked.
UK electricity output since 1896 Latest: 3.57M MWh (1998) Source: Our World in Data
World electricity generation Latest: 31.8k TWh (2025) Source: Our World in Data