Due to its swanky, clean and air-conditioned coaches, it is now a lucrative commuting option for office-goers, shoppers, and even college students

The Delhi Metro has completely revolutionised the mass transport system in India, standing out as a shining example of sustainable transportation at a time of rising environmental concerns. Carrying a peak average of over 50 lakh commuters daily, the urban rail network has seamlessly taken several initiatives to reduce its carbon footprint without compromising on its services.

In fact, the United Nations has certified the Delhi Metro as the first metro rail in the world to get carbon credits for reducing Greenhouse Gas (GHG) emissions. The Delhi Metro claims it has helped reduce pollution levels in the city by an estimated 6.3 lakh tons every year.

Since opening its first corridor – between the capital’s Shahdara and Tis Hazari – in December 2002, the Delhi Metro today has a vast network covering  areas in Noida and Ghaziabad in Uttar Pradesh, and Bahadurgarh and Ballabhgarh in Haryana. Because of its swanky, clean and air-conditioned coaches, it is now a convenient commuting option for office-goers, shoppers, and even college students, especially during the punishing summer months.

One of the greatest benefits of the Delhi Metro perhaps has been reducing the vehicular load on the city roads, although there’s still room for improvement –  for example increasing the frequency of trains between Delhi and its satellite cities.

Fig 1: A view of Delhi metro. Credit: PTI Photo

How does Delhi Metro reduce its carbon footprint? What measures has it taken to reduce global warming?

Here are some of them:

  • Renewal Energy : The Delhi Metro Rail Corporation (DMRC) has made serious efforts to meet a large part of its total energy needs through solar energy. It currently gets about 35% of its total energy needs from renewable energy. The corporation aims to ram up this figure to 50% by 2031. A significant part of this energy demand is met by an offshore solar plant in Rewa, Madhya Pradesh. DMRC has already installed rooftop solar panels at metro stations and depots. It now plans to install vertical solar panels along its elevated corridors.
  • Mitigating Air Pollution : Delhi’s geography and its varied climatic conditions undoubtedly play a major role in increasing air pollution in the region. However, vehicular emissions are possibly the next big reason for high air pollution in Delhi-NCR. This situation has arisen due to a rapid growth of private motor vehicles that run on fossil fuels. Delhi Metro plays a crucial role in mitigating this problem by providing an alternative and efficient transportation system. Many people park their vehicles near metro stations and take the rapid rail service to reach their offices daily.  To encourage commuters to shift to the cleaner electric vehicles (EVs), many Delhi Metro parking lots now have charging infrastructure.

    Fig 2: Metro stations are designed to maximise natural lighting and ventilation. GQ Images

  • Energy Efficiency Measures : The Delhi Metro employs regenerative braking technology. This unique  technology captures the energy produced during braking and reuses it, thereby reducing energy consumption. Moreover, metro stations are designed in a way that maximises natural lighting and ventilation. This minimises the need for artificial lighting and air conditioning. These energy-saving measures enhance the overall sustainability of the metro system and reduce its carbon footprint.
  • Green Initiatives : Besides installing solar panels, the DMRC has implemented rainwater harvesting systems across metro stations and depots for water conservation. Waste management practices are also integrated into the metro's operations, promoting recycling and reducing waste sent to landfills. It conducts regular campaigns to educate commuters about sustainable practices, including waste segregation, energy conservation, and reducing their carbon footprint.As part of its green initiatives, the Delhi Metro ran a fleet of 100 electric buses to provide last-mile connectivity to commuters. It later decided to hand over them to the Delhi government for better utilisation of the vehicles. The DMRC also runs electric three-wheelers on select routes to provide clean mobility options to commuters. Also, the Delhi Metro has partnered with various service operators for first- & last- mile connectivity like Smarte and ETO Motors.These initiatives demonstrate DMRC's holistic approach to sustainability, making the Delhi Metro a model to be emulated in other parts of the country for reducing pollution and shifting to clean mobility. By harnessing renewable energy and promoting green initiatives, the Delhi Metro has set an inspiring example for other cities to emulate the sustainable transportation system.On the other hand, a 2018 study suggested that the Mumbai Metro was yet to achieve reduction in GHG emissions since a major shift occurred from public transportation. The study, however, said the metro rail can better its emissions reduction record with increase in ridership.However, the DMRC, whose network is stretched over 390 km with 286 stations, can take inspiration from metro/subway systems in more developed cities around the world in reducing its carbon footprint further. For instance, Beijing's metro system, which is Asia’s largest and has a total network of 783 km with 27 lines and 459 stations, helps reduce 73 lakh metric tons of carbon emissions each year if commuters abandon driving and take the rail-based transit system , according to a Chinese state media report.

    Similarly, the Metropolitan Transportation Authority, which is responsible for public transportation in New York City including the 399-km-long subway network, says it avoids a net 170 lakh tonnes of GHG emissions annually.