India researchers look to solar to fix energy problem

Scientists are analysing 22 years of Nasa data to determine which parts of the country are best suited for commercial power plants.

Villagers inspect solar panels at the Gujarat Solar Park in Charanka village, in Gujarat state. Research suggests that the state, along with Rajasthan and Karnataka, is flooded with enough sunlight toShow more

NEW DELHI // In a country that can appear to be perpetually awash with sunlight, TV Ramachandra is working hard to find the sunniest spots in the land.

Prof Ramachandra, from the Indian Institute of Science in Bangalore, is leading a group of researchers analysing 22 years of solar energy data from the records of the US National Aeronautics and Space Administration (Nasa).

The objective is to find India's solar hotspots - locations that are best suited for the installation of commercial solar power plants.

"As a country as a whole, India is blessed with solar energy," Prof Ramachandra said. Even in Himachal Pradesh, a hilly state in India's north, he said, there is some potential. "But you have to look at the data to figure out the best spots."

Renewable resources contribute about 11 per cent to India's electricity generation; of that, solar energy comprises merely 0.01 per cent or about 18 megawatts per year.

India's plans for solar energy are ambitious. Under the US$19 billion (Dh90bn) National Solar Mission, launched last January, India hopes to generate 1,000 megawatts of solar power annually by 2013, and as much as 20 gigawatts by 2022. A gigawatt of energy can power nearly a million homes. The scope for solar power in India is immense. A recent infrastructure advisory report from Crisil, a ratings and research agency, estimated India's solar potential to be five trillion kilowatt-hours per year. That figure is far higher than the 568 billion kilowatt-hours of power consumed in 2007, according to the Energy Information Administration.

The solar mission, Prime Minister Manmohan Singh said last year, occupies "pride of place in India's National Action Plan on Climate Change". The government's encouragement of solar power plants - and the subsidies and incentives available therein - have tempted many companies into the solar energy field.

Last September, for instance, when the state-run National Thermal Power Corporation invited bids for solar power plants, it received more than 400 applications - what one executive called an "overwhelming response".

But most of these companies are, by necessity, basing their strategies on the shallow fund of solar radiation data currently available. India has only 45 radiation stations across the country - hardly enough to provide a comprehensive picture of its solar energy potential.

"Right now, the meteorological department is the main source for most of the data, and whatever is available is not all that accurate," said Jagat Jawa, the director general of the Solar Energy Society of India, the country's chapter of the non-profit International Solar Energy Society.

The ministry of new and renewable energy is trying to establish more radiation monitoring stations around the country, said Mr Jawa. That new data will be supplemented by studies such as Prof Ramachandra's, which is supported in part by the ministry of environment and forests.

"Looking at the country, you have to ask which pockets are really good for solar energy - whether they get, say, sufficient sunlight for six months of the year or eight months of the year," Prof Ramachandra said.

Many places in India, the research group found, receive an average of four radiation units per square metre - enough to set up solar water heaters. Some hotspots received six or eight units per square metre, indicating a suitability for larger power plants.

The research - which Mr Ramachandra is now preparing for publication - suggests that the states of Rajasthan, Gujarat and Karnataka are flooded with enough sunlight year-round for large power plants. The states of Kerala, Uttar Pradesh and Andhra Pradesh, he said, are better suited to smaller plants.

Radiation data aside, Mr Jawa noted other challenges to the solar mission.

"You have to look at how available land is, and at what rate. In cities, even if the radiation is sufficient, the land is often not there to build plants," he said. "You also need a lot of water for solar thermal power plants."

But Mr Jawa is optimistic: "I'm very confident. Solar energy is going to be big."