The only form of
heat is the sun

First evidences
of fire

Fire used under
human control

Fire used to heat
Neanderthal
buildings

Braziers used in
Romania

Under floor heating
used in present day
North Korea

Greek and Romans use
under floor heating

First use of fireplace
chimneys

Chimneys become common
and coal is introduced as fuel

The Franklin stove is invented
and burns fuel far more efficiently

Russia invents the radiator

The first electric heater is
invented by Thomas Edison

The US uses its first
solar water heater

Robert C. Webber builds
the first ground source heat
pump

SolarWall is created –
inventing solar air
heating

First ultra low energy
building built in Germany

Micro-CHP systems
introduced to the market