An effort to use solar power to meet part of the electricity needs at Pune and Nampally railway stations have proven to be a success
In the last few years, solar power has penetrated India’s transportation sector in a big way. One of the best instances is that of Kochi airport in Kerala, which made news for being the world’s first airport to be powered by solar power, paving the way for others to follow suit.
Taking a cue from the aviation sector, the railways too have realised the benefits of switching to sun power. The Indian Railways has announced that by 2020, it plans to generate around 1,000 MW of solar power and the figure may be scale up to 5,000 MW by the year 2025.
On July 14 last year, Indian Railways rolled out its first train with rooftop solar panels. See: India to have more solar-powered trains
Encouragingly, stations powered by sun power have also come up in two cities of India — one at Pune (162 kWp) and the other at the Nampally station in Hyderabad (227 kWp).
As per the Companies Act, every company in India needs to set aside 2% of its profits for Corporate Social Responsibility (CSR) activities. In this regard, the CSR wing of Persistent Foundation, which works in areas such as health, education and community development, donated a solar power plant to the railways to the Pune railways station — a pilot project, which was the first of its kind in the country.
This was followed by yet another installation at Hyderabad’s Nampally railway station. In order to execute the project, Persistent Foundation tied up with Sunshot Technologies, a solar energy company based at Pimpri-Chinchwad in Maharashtra.
The initiative at the Pune station was driven by the fact that it is green energy, Vaibhav Nikam, assistant manager of Persistent Foundation, told indiaclimatedialogue.net. “Also, Pune is where we are based and being our first project, it would be easier for us to implement. This was followed by the Nampally station in Hyderabad.”
Executing the project
Before the installation, apart from an analysis of the power consumption pattern at the two stations, all the possible places where it was feasible to install the panels was done and was followed by meetings with railway officials. Subsequently, the respective capacities were finalised at both the locations.
Explaining the manner in which the panels at these stations work, Rahul Dasari, Director of Sunshot Technologies, told indiaclimatedialogue.net, “The solar panels were installed on the rooftop space available at the stations. In the case of Pune, the panels were installed on the RCC rooftop of the reservation building and on platform No. 1, while at the Nampally station in Hyderabad, the panels were installed on the metal sheet roof of platform No. 5 and 6.”
Power generated through these panels is converted from DC to AC through solar string inverters and the AC power is directly injected into the railways’ main electrical power panel. The system works in sync with grid power. The arrangement is such that at any given point of time, solar power is consumed on priority and the balance power is taken from the grid.
Additionally, the system is synchronised with diesel generator sets along with grid power. Therefore, solar works in sync with DG sets in case there is a power failure from the grid, and this is facilitated through proprietary power reduction algorithm-based controllers.
Since the system does not have many moving parts, there are usually no mechanical damages. The operation and maintenance activity includes cleaning the solar panels twice a month. Others include checking electrical components like inverters, isolators, solar panel, DC and AC cabling on a regular basis, Dasari said.
Electricity generated through solar has helped in reducing power consumption to a large extent and the numbers speak for themselves. At the Nampally station, the power generated through solar is contributing to about 16.4 % of the total electricity consumption of the railway station. The solar plant generates 315,000 units of electricity, helping reduce about 260 tonnes of carbon emissions. This reduction is equivalent to reducing smoke from 190 small cars in a year and planting about 43,000 trees.
Similarly, the solar plant at the Pune railway station generates about 240,000 units of electricity, thereby helping reduce 195 tonnes of carbon emissions. This is equivalent to reducing smoke emitted from about 150 small cars a year.
Apart from producing clean energy, the effort has proven to be cost-effective too. For instance, the Nampally railway station currently generates 315,000 units of electricity through solar. Considering the current distribution company (Discom) rate of INR 8.10 (USD 0.13) per unit, the railway station is saving about Rs 2.56 million annually.
On the other hand, the Pune Railway Station generates about 240,000 units of electricity. Considering the Discom rate of Rs 9.10 per unit, the station is saving about Rs 2.19 million annually since the power generated is helping reduce about 30% of its total electricity consumption.
A cloud-based technology system was developed for the project and the system continuously monitors the status of the solar modules, inverters and the weather sensor. The intelligent system can send notifications if these components are performing below the set parameters. The system also measures and logs readings from Railways’ Discom meters and diesel generator sets. This helps the customer to clearly understand the actual solar generation and consumption through solar, Discom and diesel generator sets on a daily-monthly basis. Constant monitoring leads to better control and cost reduction.
Explaining why Sunshot developed its own system, Dasari said, “It was decided to have an online monitor and control system to maintain maximum up time of the plant. The system is very useful for conducting preventive maintenance activities as any fault in the system immediately comes as a notification to the concerned maintenance engineer and that can be sorted before the entire solar plant breaks down and the goal is zero downtime.”
Despite an announcement in this year’s budget about 700 stations being powered by solar, in reality things aren’t going as rapidly. As of now, companies have not been approached to take up projects similar to Pune and Hyderabad. At times, for instance in the case of the Nagpur railway station, it wasn’t viable. “Things didn’t go as planned. We undertook a survey, but there was no space and we realised that on the rooftop we can’t provide solar panels. It wasn’t feasible,” Nikam told indiaclimatedialogue.net.
The Ministry of Railways has announced that it has plans to sanction solar power system on 24 coaches of suburban trains and is likely to approve similar provisions with flexible solar panels on 250 more coaches. Companies like Sunshot are working on flexible modules, which can help meet the needs of the Railways, Dasari said.
Nikam believes that for better implementation, the procedures need to be eased. “We have the plans, the funding and execute it accordingly. Only the procedures should be hassle free so that the project is not delayed unnecessarily. Green stations are a good idea, but there is need for more support from the government in that there are standardised procedures.”
The government, he suggests, could also ask the corporate sector about the targets so that they achieve the desired project.