Hybrid trains with solar panels start rolling in India

To run its rail network, India consumes almost three million liters of diesel fuel. Half of the passenger trains that travel the 66.000 km of its railway network run on diesel locomotives and, to a lesser extent, on biodiesel. The other half is electrified.

The government company that manages the railway network, Indian Railways, transports more than 23 million people and 2,65 million tons of goods every day. That magnitude of numbers requires a change of model, and the company has started to implement it, to become a clean company, and reduce its CO emissions₂ in a drastic way.

Despite the large number of diesel-powered train machines still in service in India, the country has the double honor of being the first to introduce diesel-powered machines. compressed natural gas (which despite being a fossil fuel, emits fewer polluting particles), and also being the first railway network to have incorporated hybrid diesel locomotives. That is to say: trains that obtain part of the electricity they consume from the sun's energy.

India's earliest attempts to incorporate solar panels into its trains date back about 4 years ago, when the company partnered with the Indian Institute of Technology to develop a solar power system to power the lighting and air conditioning in the passenger cars. In order to reduce diesel consumption.

But after many tests, it was not until last July that Indian Railways has inaugurated the first DEMU trains (diesel electric multiple unit), which are the result of that research: wagons that incorporate solar panels on the roof. Although the train goes on being powered by diesel engine locomotives, a set of 16 solar panels on each car replaces the diesel generators intended to run the electrical systems of the cars.

These wagon roof panels provide 300 watts of electricity to the LED lamps, the ventilation system, the air conditioning and the information screens for the passengers. A battery system provides up to 72 hours of autonomy, for the hours in which the train operates without sunlight, either because it is night or because there is fog.

In total, it is estimated that the fuel savings will be 21.000 liters of diesel per year for each hybrid train with six wagons, which means a reduction in the emission of carbon dioxide (CO₂) of about 9 tons per wagon / year. In total there are about 50 wagons, and it is planned to add solar panels to 24 more wagons in the coming months.

In fact, it is quite a difficult task, since normally the solar panels are installed on fixed surfaces, be it land, roofs or lately in structures above water, and in this case they are mounted on top of vehicles that circulate at an average of 80 km / h.

One of Indian Railways' goals is to save fuel, as well as reduce CO2 emissions on its thousands of trains and in other ways. For this, the wagons incorporate ecological dry toilets, which do not use water, in addition measures to recycle the water from the sinks, management and recycling waste, and to finalize an ambitious plan that includes planting 50 million trees near train tracks and stations

By 2020, Indian Railways' electricity production capacity is projected to be 1 GW using solar panels (5 GW in 2025) and 130 MW using wind turbines, which will provide clean, emission-free electricity directly to trains and stations. This should result in a "Electric mix" of the Indian rail network which, by 2025, will get 25 percent of its electricity from renewable energy sources as published by the government (Decarbonising the Indian Railways).