Started recently in the coaches of a suburban train, the initiative will soon be scaled up in line with India’s larger aim to increase use of clean energy
In a pioneering effort for transition towards clean energy and reduction in the carbon emissions, Indian Railways has launched the world’s first solar-powered train in New Delhi. Each of the six coaches in the DEMU (diesel electrical multiple unit) train is fitted with a 4.5 KWp capacity solar system consisting of 16 solar panels of 300 Wp each, which are adequate to power the fans and lights of the coach.
“Indian Railways has taken a path-breaking leap towards making Indian Railways’ trains greener and more environment friendly. Hon’ble Prime Minister Shri Narendra Modi has also been emphasising on use of green energy and environment friendly measures. Indian Railways is committed for environment conservation and use of cleaner fuels. Indian Railways is trying to increase use of non-conventional sources of energy,” Railways Minister Suresh Prabhu said at the launch. “More solar powered trains may be inducted in future.”
The latest initiative has come as boost for the Indian Railways, which is already embarking on a green mission and has laid a target of 1000MW solar plants in the next five years. See: Indian Railways to rapidly reduce carbon footprint
DEMU trains typically provide power for its passenger comfort systems — lights and fans — from a diesel driven generator, but the six-coach train running on solar energy can cut the consumption of polluting diesel fuel by 21,000 litres and reduce carbon emissions by 54 tonnes per year.
Additionally, each solar coach that comes at a cost of Rs 9 lakh (USD 13,967) at the prototype stage can lead to cost savings worth Rs 2 lakh per year due to reduced diesel usage. Since the solar power system come with a warranty of 25 years, one coach can potentially save Rs 50 lakh in 25 years. Hence, the return on investment is pegged between 4 to 4.5 years, making it economically viable and lucrative to upscale it in the long run.
“This is the first time in the world that such a technology involving solar panels is being used in railways. We are the pioneers. Full train component and charging points have been made in India itself and even concept preparation, research and design has been done within the country,” an official in the railway ministry involved with the project told indiaclimatedialogue.net.
The train will do multiple trips daily from Sarai Rohilla in Delhi to Farukh Nagar in the neighbouring state of Haryana for two months before it is put in the commercial service. “The plan is to monitor the performance and review the pilot solar train and then extend it to four trains of six coaches each to begin with,” said Anil Saxena, Director General, Public Relations, Railway Ministry.
Research equipment and data loggers have been installed to track performance, which will help in generating useful data for adapting the system for future rollout of solar trains.
Powering through sun not just saves diesel, fuel costs and cuts carbon emissions but this solar train technology has come as a solution to the challenges that are often encountered in shifting towards solar energy.
“1 Kw capacity solar system needs 10 square metres of space, so normally extra land is needed to install solar. But in this case we are utilising existing rooftop of coaches and so it doesn’t require space on land,” the ministry official said. “Plus, the electricity generated is used within the train itself, so there is no transmission loss, so we are saving on energy loss as well.”
The solar train lacks air conditioning. However, if the experiment and performance goes according to plan, solar-powered air conditioners may be installed as well. Technical experts from the government say that such ACs will require less energy.
“You must have noticed that a car becomes really hot inside when parked under the sun. Its roof becomes really hot. Same thing happens with trains. Now if we cover the roof of a train with solar panels, almost 30% of the incoming heat can be trapped. So that will cut the energy required to run ACs inside its coaches,” said an expert from the ministry of railways who didn’t wish to be named.
The complete installation, design and manufacturing of the solar modules has been done by a Greater Noida-based company Jakson Engineers Ltd. Other parts were procured from original equipment manufacturers.
First off the block
Having no such precedent across the globe, creating a solar train was challenging. “One of the biggest challenges while designing for the rooftop was that there was only limited area available on the rooftops of train for installation. It had to be worked around the available train area. Then another challenge was that the solar panels shouldn’t fly off the trains when they pick up speed,” Nirdosh Gupta, who is heading rooftop solar business of Jakson Engineers Ltd, told indiaclimatedialogue.net. “We used in-house facilities for designing and installation and these panels can withstand a speed of 160-180 km per hour.”
“There was no analysis available with us of radiation data for train rooftops,” Gupta added. “So far you have panels on rooftops of buildings but those are all stationary and one knows how much of solar radiation falls on the panels but we just didn’t know how much solar radiation these panels would get once they were installed on a moving train.”
Before this, sample coaches of North West Railways were powered by solar energy but the technology used was different as the solar power was directly synchronised. This is the first time that a battery-based solar train has been put on the tracks, definitely a few notches better than the previous one.
“In the North West Railways, the technology was totally different. There the solar electricity cannot be used at night while in this case the solar batteries can take the entire load of running fans and lights in coaches for full 24 hours if needed,” said Gupta.
The system is capable of generating an average of 20 kWh of energy on a daily basis throughout the year and the surplus power generated during peak hours is stored in a 120 AH battery system.
But as far as powering AC coaches are concerned, according to Gupta, it is still a long way ahead and may not be viable due to heavy load and limited space available on train rooftops.