NEW DELHI: Delhi Metro has become the first rail network in the world to get a UN certificate for preventing over 90,000 tonnes of carbon dioxide from being released into the atmosphere, by reducing its power requirement in three years.
Germany-based validation organisation TUV NORD, which conducted an audit on behalf of the UN Framework Convention on Climate Change (UNFCC), found that the DMRC stopped the emission of 90,004 tonnes of carbon dioxide from 2004 to 2007 by adopting regenerative braking systems in the Metro trains.
"The UN certificate was given to the DMRC for preventing over 90,000 tonnes of carbon dioxide from being released into the atmosphere, thus contributing to the fight against global warming,'' Delhi Metro spokesperson Anuj Dayal said on Sunday.
For replacing the conventional electro-dynamic braking technology with the regenerative braking process, DMRC has earned carbon credits. In this process, whenever trains on the Metro network apply brakes, three phase-traction motors installed on them act as generators to produce electrical energy which goes back into the overhead electricity (OHE) lines. The regenerated energy that is supplied back to the OHE is used by other accelerating trains in the same service line, thus saves overall energy in the system and about 30% of electricity requirement is reduced and subsequently leading to GHG (green house gases) emission reduction.
DMRC saved 1,12,500 megawatt hours of power generation by restricting and reusing power on its trains through regenerative braking, thus saving the emission of 90,004 tonnes of CO2 into the atmosphere from 2004 to 2007.
It is estimated that in 2008, 39,000 tonnes of carbon dioxide were prevented from being emitted and this figure will increase to over 100,000 tonnes per year once phase-II of the Metro is fully operational.
