Can Trains Run Purely On Solar Power?
Is such a thing even possible? Wouldn’t its energy requirement be too large for solar alone to fulfill? And what about running through the night, through a long tunnel or an overcast day?
As it turns out, scientists at the Indian Institute of Science (IISC), Bangalore have already been considering the possibility of developing a train run entirely on solar power.
They are in talks with manufacturers in Kapurthala (Punjab) to see if solar modules could be installed on the roofs of rail cars. Admittedly, the manufacturers’ initial response has been skeptical because of the engineering challenges involved.
Firstly, they are concerned about whether the modules could withstand the constant vibration coming off of the tracks. And secondly, given that trains move at speeds in excess of 100 km/h, the solar modules would have to withstand considerable wind loads (if mounted on racking structures).
Of course one solution could be to integrate the modules into the rail car rooftops. This would shield them from the wind loads and also obviate the need for any mounting structure. However, this would then present the challenge of properly orienting the modules with respect to available sunlight, as the train will inevitably change direction while moving from one point to another.
Then there is the question of generating enough power. Given that rail cars are long and narrow, the surface area available for installing solar modules may simply not be enough to generate all of the trains’ energy requirement. Erratic shading from trees, tunnels and cloud cover may also interfere with adequate power generation.
Solar Trains Stations – A Viable Alternative
However, one viable alternative is to generate the solar power in or around train stations. Most have ample roof space available, are exposed to the sun as long as it is shining and could very well power at last their own operations through solar alone, or in combination with another (preferably clean) source of energy.
They could also feed excess power into the grid which could in turn be used to power electric trains.
What would that mean for lowering emissions? Research from the IISC states that, theoretically, running on solar power alone could reduce the consumption of diesel by up to 90,000 liters (annually) for a typical Indian train. This implies a 2,340 ton reduction in CO2 emissions per train per year (at an emission level of 2.6 kg of C02/liter of diesel).
As for costs, at an average of Rs. 50/liter of diesel, that’s an enormous saving of Rs. 45 lakh per train per year. Add to that the fact the Indian Railways network runs about 11,000 trains every day, and it adds up to an annual savings of nearly Rs. 5,000 crores.
Fortunately, such a transition is already happening. The Delhi Metro Rail Corporation (DMRC) has installed 500 kWp worth of solar panels on one of its stations (Dwarka Sector 21). Given that the Delhi Metro has 140 stations, that alone – at an average of 200 kW – is 28 MW of solar power, enough to power quite a few metro rail cars.
Therefore even though solar panels on rail car rooftops may not be entirely feasible, the trains nevertheless can go on solar power.
To read more about the concept of solar trains, click here.