25% of Indian Railways could run on direct supply from solar panels: Study

Direct solar supply could also rapidly cut Railways’ emissions by 6.8 million tonnes CO2 each year–just over the entire annual emissions of Kanpur, says study

Direct supply of solar energy to Indian Railway lines–without the need to connect via the grid– could save almost seven million tonnes of carbon a year, according to a new study.

It could also power at least one in four trains on the national network on competitive terms, stated the study by Indian NGO Climate Trends and UK-based green-tech start-up Riding Sunbeams.

The report titled, ‘Indian Railways Opportunity for Connecting Solar PV Generation’ examined Indian Railway’s net-zero plans. It presented results from a study analysing the total share of the national transporter’s traction load that could be met with direct solar photovoltaic arrays. Traction load is the power required to move trains in a railway network.

Indian Railways’ net-zero trajectory

Recently, Indian Railways set a target to become the world’s first net-zero emissions railway by 2030. According to the report, if the target is met, it could lead to an annual emission reduction of at least 15 million tonnes of CO2, which could help India meet 5% of its Nationally Determined Contributions (NDC) target.

Railways’ clean transition can be a major source of inspiration for India and the world, said Ajay Mathur, director general, International Solar Alliance (ISA).  “Indian Railways’ goal of net zero emissions by 2030 could see over eight billion passengers travelling emissions-free every year after that,” he added.

According to the report, Indian Railways accounts for 4% of India’s total greenhouse gas (GHG) emissions. The national transporter used 17,682 terawatt-hour electricity, 2,749 billion litres of diesel, and 1,000 tonnes of coal during the financial year 2018-19. 

In 2018, the government approved plans for 100% electrification of railways by 2023, which was then  pushed ahead to 2030 by the Railways last year. By March 2021, almost 71% of India’s conventional tracks were electrified, making it the third-largest electrified system in the world after Russia and China.

In a move to integrate renewable energy, the national transporter tendered 3 GW of land-based solar in 2020, along with 103 MW of installed wind energy plants. It is also planning to make 51,000 hectares of land available for potentially 20 GW of land-based solar. 

Indian Railways is one of the biggest renewable investors. The investment curve of railways in renewable energy has been moving up in the past decade. In 2009, it committed to source 10% of its energy from renewables and in 2015-16 it planned to install 100 MW of solar and 150 MW of wind energy by 2020. Last year, it committed to increase its land-based solar systems by installing 20 GW of solar on vacant land by 2030.

“With abundance of solar resources and low-cost renewable power, Indian Railways can witness significant cost savings and CO2 emission reductions by switching to solar-to-rail. Moreover, it will also be important for India to fast-track the cleaning of the grid to complement the stand-alone solar system to achieve its net-zero target,” said Akshima T Ghate, principal at RMI India. 

The report stated that achieving net-zero by 2030 will save $2.3 billion in fuel costs and other savings per year. Additionally, the approved electrification would generate around 20.4 crore man days during construction. Currently, grid-connected solar can generate 115,000 jobs, according to the International Renewable Energy Agency (IRENA). This number could double if it includes off-grid deployments such as direct supply to the rail traction system, the report said.  

According to the Indian Railways, its decarbonisation initiatives will make it the first transport organisation to be energy self-sufficient. This means that the Railways’ future energy consumption (estimated to increase from 21 billion KWh to 33 billion KWh by 2030) will rely entirely on renewables, the report stated. 

Direct connection of solar PV to meet Railways’ net-zero target

Indian Railways is one of the world’s largest networks, which employs more than a million people. Around 23 million people use it as a mode of transport daily and it also carries 1,160 million tonnes of freight annually, making it India’s largest electricity consumer and third-largest diesel consumer.

Since Indian Railways is the third-largest diesel consumer in India, its plan to be fully electric by 2023 will reduce the consumption of high-speed diesel oil by 2.83 billion litres per year. 

The report revealed that the conversion of diesel traction to electric would cause a 32% increase in CO2 emissions initially because of India’s reliance on coal to produce electricity. It said the national transporter would need to either procure its own clean electricity supply from wind and solar generators directly connected to the railway network or establish new grid-connected renewable projects in order to match the traction energy supplied via the electricity grid, to mitigate the emissions.

Indian Railways’ plans are already underway to deliver 20 GW of solar generation to match the growing demand for energy to move trains. The report studied the energy demand of 16 out of 18 railway zones to assess the traction load that could be met with direct solar PV. 

The top five zones with the greatest solar-to-rail potential are: South Central Railway (394-625MW): [Tamil Nadu, Kerala, (also serves Karnataka and Pondicherry)]  Central Railway (299-475MW) [Maharashtra] Northern Railway (290-459MW) [Punjab, Haryana, UP, Delhi] Western Railway (280-443MW) [Maharashtra, Gujarat, Rajasthan, Madhya Pradesh] West Central Railway (278-440MW) [Madhya Pradesh, Rajasthan, and some in Uttar Pradesh] *The calculations assume that all of the energy generated by the solar is used by the railway, and do not include the potential for battery storage integration

It considered two load profiles–the flat and the commuter profile. While the flat profile assumed traction demand was constant every day of the year between 04:00 and 23:00, the commuter profile assumed a morning and evening peak.

The new analysis highlighted that for the flat profile, around 5,272 MW of solar PV generation could be fed directly into the railways’ overhead lines, which is estimated to reduce emissions by 6.8 million tonnes of CO2 per year, while for the commuter profile it was 3,338 MW.

“Building on the ambitious goal for 100% electrification of the Railways, it would be logical to embrace and scale up solar and wind for our railways to reach net-zero emissions by 2030,” said Arunabha Ghosh, CEO, Council on Energy, Environment and Water (CEEW). 

According to him, in the immediate run, the Railways could focus on greening their electrification system and substations. Installing rooftop systems on station buildings and workshops could also result in significant cost savings, he said, adding, in the long term, green hydrogen is another promising option to power the Trains.  

How achieving net-zero will help Indian Railways

Since the maintenance cost of the electric locomotives is half as compared to diesel locomotives, complete electrification will help the Railways to reduce its expenditure. Moreover, complete electrification could save $1.8 billion per year in fuel bills.

Increasing renewable energy production could also help the Railways reduce power procurement costs. Additionally, moving to renewables could attract $4 billion in private investments. A meeting held last year between the government and private investors gained attention from some big conglomerates such as Adani, NTPC and Tata Power.

Going beyond net-zero

Indian Railways is one of the most sustainable forms of transport in terms of both energy use and carbon emissions. The national transporter’s low-carbon growth strategy can help India achieve its 2030 emissions reduction goals. Around 5% of the NDC target would be met if the Railways deploys 100 GW of solar power, according to official estimates.

The International Energy Agency (IEA), in its 2019 report ‘Future of Rail’, had also estimated that high railway use could avoid 315 Mt CO2eq emissions and six kilo-tonnes of fine particulate matter (PM2.5) emissions per year by 2050. To achieve this goal, the Climate Trends and Riding Sunbeams report recommended that the railways and the government should further enhance the role of trains.

The report said the dedicated freight corridors (DFCs) and high-speed rails could improve connectivity across the country and reduce travel time. For example, the Maharashtra Ahmedabad high-speed rail (MAHSR) corridor could reduce travel time from approximately nine hours (by bus) to two hours when it becomes operational in 2023. 

Moreover, DFCs would carry longer freight trains with more load and speed that will help to reduce freight traffic on existing lines and help in improving passenger train reliability.

Ghate also suggested that along with the electrification of rail, Indian Railways can look for opportunities to enable a higher share of freight moved via rail because that can deliver overall decarbonisation benefits to the nation.

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