Dynamic heating of the metro third rail in Paris (RATP)

The RATP metro network has a top-contact third rail to supply energy to the metro trains. This situation leads to high energy use, because the third rail must be heated in winter to avoid the accumulation of snow and ice.

RATP evaluated the conditions under which it is necessary to heat the third rail and how the energy consumption of heaters could be reduced. It implemented an intelligent controller along test lines. The heating control is based on actual measurements of weather parameters via one or more weather stations measuring temperature, wind speed and rain or snow. So heating devices are activated only when required, thus reducing the energy consumption.
Technical data

Investment costs (€)


Energy savings (%)


Annual energy savings (kWh)

25,200 kWh

Annual CO2 savings (TCO2)

2 TCO2

Payback time (years)

4 years

 Investment sheet: RATP Heating Third Rail Metro