The Chennai Metro Rail system has made a great move toward energy efficiency by adopting the Regenerative Braking Technology to save power and reduce the release of harmful carbon emissions. According to the Metro rail officials, a four-car train running 400km per day consumes around 6,300 kilowatt-hour (kWh). By using the regenerative braking system, each train can generate nearly 1,900kWh, i.e. 30% of the energy consumed. Thus, by meeting 30% of power needs, metro trains are cutting down carbon emissions as it reduces dependency on power supplied from fossil fuels.
Any moving train creates kinetic energy (proportional to speed) and whenever brakes are applied, the vehicle slows down, losing its energy in the form of heat. This energy wastage is avoided in regenerative braking system, as the three-phase traction motors fitted in trains act as power generators whenever the brakes are applied, turning the kinetic energy of the train into electrical energy that goes into the overhead lines.
This regenerated power is mostly used by the train in the same electrical section and the remaining is fed back to Chennai metro rail’s 33KV network. Sometimes the power is used for lighting and running other auxiliary systems on board. Chennai Metro officials said that the regenerative braking system can reduce dependency on the state grid and all their train cars have traction systems to generate power, unlike in EMUs, where only the locomotive does.
Date: 19.02.2018 | Source: Times of India