Indian Railways is one of the largest consumer of both diesel oil and electricity in India. It uses 2.7 billion litres of diesel and around 20 billion KWh of electricity per year for traction purpose. Additionally another 2.5 billion KWh is used for non-traction related usages like powering stations and other things. This 2.7 billion litres of diesel could typically provide around 9 billion KWh electricity assuming 35 percent diesel generator efficiency. That way altogether the energy requirement of Indian Railways could be around 32 billion KWh of electricity.
As far as land is concerned, the total land available with the Indian Railways is 4780 sqkm, out of which 510 sqkm land is vacant. This is a huge amount of land which could be more than some of the smallest states in India. For example that is 322% of NCT Delhi, 129% of Goa and 67% of Sikkim.
Indian Railways manages the third largest railway network in the world. This is with a route length of 67956 km. If double lines and other multiple parallel lines are counted the running track length comes to 99235 km. If all other tracks including yards, multiple platform loops in stations etc are counted then the total track length would come to 126366 km. Lion share of that meaning 94.1% of all the route is Indian broad gauge. That is 1676 mm or 5 ft 6 inches gauge.
What is the total land used by tracks?
The minimum loading gauge of the broad gauge track is 3.25 metres. But, let us assume a width of 4 metres for easy calculation. Considering 125000 kms, then the total area would come to 500 sqkm.
When railway lines are covered with panels how many MW of solar panels could be installed?
Assuming 2m x 1m panel producing 350 Watts, then nearly 3000 panels would be required to get an installed capacity of 1 MW. With 4 metre track width two parallel panels could be used. That way, with 1.5 km of track length 1 MW of installation could be achieved.
Considering, 126366 km of track length, 84000 MW could be installed. But, that is impractical as 100 percent track could not be covered, because of different reasons – solar insolation, loading gauge, bridges, tunnels, trees, stations and many more.
How many KWh could be generated?
In India 1 KW system could generate around 4 KWh to 4.5 KWh of electricity per day, so we can assume that 1 MW system generates 1500 MWh of electricity annually. With 84000 MW of installation, 126 TWh or 126 billion KWh of electricity could be generated.
With all these considerations, even if 25 percent of the railway tracks could be covered with solar panels, there is a potential to generate more than 30 billion KWh of electricity so that the whole Indian Railways could be powered.
Here we are only talking about the 500 sqkm of land on top of the railway tracks. Another 510 sqkm is vacant. Apart from that there are huge amount of covered spaces like stations, platforms, sheds, car and bike parking etc. which could be covered with solar panels.
Solar Electricity in India
As of 2021, total solar installed capacity in India is 47700 MW and total solar electricity generation was 60.4 billion KWh.
That way, the Indian Railways could not only become self sufficient but they could become the largest solar producer to the national grid also.
References
Electricity and Diesel usage by the railways
https://www.livemint.com/Companies/SuniviCcxYRcSkGON6v1TO/100-railway-electrification-to-double-power-demand-by-2022.html
https://www.pv-magazine.com/2021/09/02/indian-railways-could-power-one-in-four-trains-with-its-own-solar-panels/
https://shaktifoundation.in/wp-content/uploads/2020/03/Energy-Efficiency-in-Indian-Railways.pdf
https://carboncopy.info/25-of-indian-railways-could-run-on-direct-supply-from-solar-panels-study/
Saurorja 