Fitting a solar panel module on the roof of a railway coach can yield more than 7,200 units of electricity every year. If implemented on all 63,511 coaches in the Railways, 450 million units of power can be harnessed resulting in savings of 10.8 crore litres of diesel and reduction of carbon dioxide emission by approximately 3 lakh tonnes.
These are the findings of a pilot field research conducted by a team of scientists from Indian Institute of Science, Bangalore, who travelled on a solar-panel fitted LHB (Linke Hoffman Busch) coach, a latest German technology bogie, which was attached to the Chennai-Coimbatore, Chennai-Mysore Shatabdi and Chennai-Bangalore Double Decker Express trains on different days during June 24-July 2. The research was carried out to assess the feasibility and viability of generating electricity on a moving train from solar panels fitted on the rooftops of trains and the impact of factors like sunshine, train speed, number of halts, track curves, etc.
The pilot study was carried out in a ‘worst-case scenario’, i.e. during the onset of the Southwest monsoon on railway routes with low sunshine due to clouds or rainfall. Hence the electricity generation in places and seasons of harsher sunshine would give a greater yield, thereby projecting a figure bigger than what was arrived at in this study.
The coach could generate a maximum of 1.8 units of electricity per day, according to the research findings. This was extrapolated to a scenario where 24 such panels (12X2 module) could be retrofitted on the coach.
Thus, the resulting yield was assessed to be 18-20 units per day. The figures for yearly savings have been arrived at by assuming that the coach would be in operation for 365 days a year in the report, though the industry standard is 330 days.
The study was done on the Shatabdi Express as it has minimum stoppages; however, the team wanted to measure the power yield at lower speeds and hence the Double Decker Express train was chosen. The team also reported on a number of practical factors which contributed to fluctuations in electricity generation during all the trial runs. A static trial was also carried out at the Basin Bridge yard here to compare the parameters with the dynamic trial.
The study is significant in the context of the shift by the Railways from conventional coaches to German technology LHB rakes, which have better safety features. For operation of electrical appliances inside an LHB coach, power supply from the End on Generation (EOG) system (a generator) is needed, which consumes 0.25 litres of diesel to generate 1 unit of electricity. If every LHB rake is fitted with 12X2 Solar Photovoltaic (SPV) module, it would result in huge energy savings as well as cut environmental pollution caused by burning diesel.
The study findings could be used to manufacture and design many such Solar Rail Coaches on a large-scale which could significantly bring down the price of the solar panels and operational costs. In addition, with increased interest in the field of solar energy research, an advancement in technology raised the possibility of a yield greater than what was obtained during the field trials, resulting in greater diesel savings and an effective solution for reduced emissions. Railway officials noted that implementation of the project on a wider scale could provide a fillip to the domestic solar panel manufacturing industry in line with the ‘Make in India’ initiative.