Generation of power is only one aspect of the solar projects.

One of the great landmarks of Kolkata is the Howrah station, which opened in 1854, and has largely remained intact over the decades. The red-bricked building is looking at a major makeover. And the one thing unique in that transformation is green energy.

The largest railway station in India is set to switch over to solar energy for all its day time electricity needs by August.

That's a lot of solar energy. The station has 23 platforms and has the highest train handling capability in the country. It also ranks as the busiest station in terms of passenger volume per day. Some 293 trains pass through the station.

What this means is that Howrah requires 10,000 units daily. Close to 60% of that - 6,000 units- is required during day time. The Howrah station was electrified completely in 1954.

The plan is in accordance with the Narendra Modi government's directive to the railways to go solar by 2025.The Modi government has been keenly working at shifting the emphasis from fossil fuel to clean energy. India's emission of carbon is just after China and America.

Work is proceeding in full flow at Howrah Station. The rooftop of the station and the 23 platforms sheds are getting ready for the installation of a 3 MW solar power plant.

Rays Expert, a company that has been partnering the Centre to set up solar plants on public buildings, is the one that the Solar Energy Corporation of India has chosen for the contract.

The plant is being set up at a cost of Rs 21 crore."Eastern Railway (ER) will not spend anything to set up the plant. We will bear the expenses, and will sell the solar power generated at Rs 5.49 per unit, against Rs 7 that ER is paying now. This rate has been fixed for the next 25 years," said Rahul Gupta, CEO of Rays Expert, recently.

Generation of power is only one aspect of the solar projects. Equally important is the work to store the energy. That work will start once generation stage is past.

Kolkata is changing in broad daylight.