He lights up buildings in Kolkata with solar power and sells it too

Coal stocks in Indian power companies are abysmally low. Supreme Court's mass cancellation of coal block licences recently will only make matters worse.

As the central government is busy strategising how to counter the impending power crisis, it can take a leaf out of the book of a Kolkata-based scientist, who has made a huge residential complex energy-efficient by installing grid-connected solar power panels.

And what’s more, this building supplies excess power to Calcutta Electric Supply Corporation.

Welcome to SIRSA, the 10-storey residential building for officials of the Council of Scientific & Industrial Research.

Thanks to Avijit Ghosh, principal technical officer of CSIR, who conceived the idea, 96 flats of the building, including a guest house, its seven lifts, 24-hour filtered water supply run on solar power.

Conservation of energy dominated Ghosh’s thoughts ever since he completed his Masters in Energy Science and Technology from Jadavpur University in 2004.

“We often tend to overlook the impending power crisis. With coal and water becoming scarce with each passing day, it’s time we adopted alternate source of energy,” Ghosh told rediff.com.

As the person in charge of maintenance of SIRSA, Ghosh thought of starting the project there itself.

“While doing my MTech, I was inspired by my guide Dr Subhasish Neogi’s ideas on alternate energy, ” Ghosh said.

“As baby steps towards reducing carbon footprint and conserving energy, I started replacing ordinary bulbs with compact fluorescent lamps (CFL) and at a later stage, light-emitting diode (LED) bulbs.”

In 2010, Ghosh’s project gained momentum with the publication of Compendium of State Government Policies on Renewable Energy Sector.

Though a Kolkata Municipal Corporation rule states that any high-rise over five-storey needs to install rooftop solar panels, it hardly gets any attention.

Ghosh thought of reversing the trend.

Inception

Ghosh prepared the proposal during 2012 and completed the formalities of gathering in-house approval, getting Ministry of New & Renewable Energy's nod for subsidy, tendering process initiation, selecting vendor and finally commissioning the same in February 2014.

At any instance, the plant at SIRSA can generate 37.5 kilowatt of energy and till September 30, it has produced 31,536 units of power.

Out of this 30,328 units were consumed in-house and 1,208 units were sold to CESC.

First steps

"As an energy scientist, alternate source of energy always intrigued me. Also, soaring energy bill was my major concern,” Ghosh said.

“I often thought of exploring the potential of solar energy,” he added.

Instead of opting for battery-driven solar panels, Ghosh and his team chose grid-connected solar power generation system mainly because of three reasons:

1. Capital cost of battery-supported system is about 80 per cent more

2. Recurring cost of replacement of batteries is high

and

3. Disposal of used battery is a hazardous proposition.

“The panels that we have installed are of high quality and can run efficiently for 25 years after which they will have to be replaced,” Ghosh told rediff.com.

Once the decision to use solar energy was finalised, a Kolkata-based agency got the contract for installation through formal and competitive bidding.

Total expenditure for the solar panels stood at Rs 37.35 lakh (including a five-year maintenance contract).

Thirty per cent of the cost was subsidised by the ministry of new and renewable energy.

Modus operandi

The solar plant covers a space of around 550 square metres.

The panels are installed at the roof of two buildings and are tilted at 20 degree, matching the latitude of the city.

They were set up after ruling out the shadow areas on the terrace, Ghosh told rediff.com.

 “We signed a 25-year power pact with CESC,” he added.

There are energy reading machines at the rooftop and on the ground floor.

While the reading machines send out the consumption statistics, they also indicate how much energy SIRSA is supplying to CESC.

By using solar power instead of conventional electricity, SIRSA has saved Rs 233,000, 52 tonnes of carbon emission and 284 kilolitres of water till September 30.

SIRSA’s average energy bill stands at Rs 1,60,000 per month.

Out of this, 55 per cent is recovered from the residents according to each household’s meter-wise consumption.

About 25 per cent of the total units are consumed by the guesthouse and 20 per cent goes for common services -- water pumps, lifts, common area lighting etc.

As for the maintenance of the panels, Ghosh’s team makes sure that there is no lapse.

“One needs to clean the panels daily at sunset with plain water to prevent dirt and moisture from clogging them,” he said.

Projects on anvil

Riding high on the success of solar plant at SIRSA, Ghosh is toying with the idea of developing bio-gas by using kitchen waste of the residents of SIRSA.

He also wants to find a way of using of fly ash effectively.

“Though much is written about the carbon footprint, very little is done.

“To make the world a greener place for our future generations, it’s important to stress on clean energy,” he said.

“I invite one and all to walk the green path. Every highrise across the world must think of using alternative energy”.

For those in India who are keen on setting up solar panels at their residence, Ghosh has a tip to offer.

A few financial organisations at present offer loans for such schemes.

Ghosh hopes more and more people will start applying for loan for solar projects in near future.