To this end, regenerative braking energy recovery converters will be installed at four substations in Madrid and two in Barcelona. Unlike AC lines, which send energy back to the grid in a natural way, DC systems such as Adif’s conventional network need converters to return the energy to the grid.
The energy produced in the braking can only be used by other trains that are in the same electrical section and the rest of the unused energy dissipates in the resistors of the train itself. This limitation is solved with inverters that make traction substations reversible.
The system recovers the energy produced in the braking of the trains not used by others and improves the environmental and energy performance of rail transport, reducing the emissions of carbon dioxide to the atmosphere.
These six projects, together with another six which are underway in other substations, will allow savings of almost 19 GWh and a reduction of emissions of about 4,400 tons of carbon dioxide per year.