HYDERABAD: Anantapur district is known for arid weather conditions and as one which receives solar radiation of 5.2 kilowatt per square meter per day. It gains significance as the district is one of the few places across India which receives heat radiation of such strength.
Utilising this natural phenomenon and to promote clean energy solutions, Megha Engineering & Infrastructures Limited (MEIL) established a 50 Mega Watt (MW) solar thermal power plant in the district, which uses concentrated solar power (CSP) technology, one of its first in south India. MEIL established this plant through its unit MEIL Green Power Limited (MGPL).
MGPL was awarded the 50 MW solar thermal power plant as part of Jawaharlal Nehru National Solar Mission (JNNSM). The mission’s target is to deploy 20,000 MW of grid connected solar power by 2022.
The plant, commissioned on Thursday, is spread across 600 acre of Nagalapuram village in Peddavadaguru mandal of Anantapur district and built at a cost of ` 848 crore. The plant is the only one, out of seven, solar thermal power plants located in south India. The six other plants are located in Rajasthan and produces 420 MW put together.
How does it work?
The plant uses a technology which is still in its nascent stages in India.
That is Parabolic Trough Technology, wherein a series of reflective mirrors are designed in the form of parabolic troughs and a thin pipe runs along focal point. Sun energy from the mirror surfaces’ is directed to the thin pipes.
A Heat Transfer Fluid (HTF) runs through the pipe which absorbs the heat energy directed to the pipes and it gets heated up to a temperature of 400 degree Celsius. Upon pumping, the HTF reaches heat exchanger, where the accumulated heat is transferred to water running around the pipes. At the high heat conditions, water is converted to vapour form which rotates the turbines and thus electricity is produced.
Ninety seven per cent of sun light that falls on the mirrors is reflected to the tube. For maximum utilisation of sun’s heat, a devise, Inclinometer, is used to track position of sun. The troughs change their position and face sun accordingly, alike a sun flower.
50 MW Power and Two States
The 50 MW power generated from the power plant will be finally sent to the National Thermal Power Corporation limited (NTPC) grid. The corporation takes care of distributing the power between AP and Telangana states. “As of now, we are increasing production capacity from 15 MW per hour. And by the end of this month, the plant will produce 50 MW,” said B Uma Maheshwar Reddy, associate vice president (AVP), MEIL. The power generated every day is sent to NTPC and sold at a cost of ` 11.30 per unit.
At full capacity, the power plant will generate 110 million units per annum. About future plans of the company, Uma Maheshwar said that they are aiming to increase the production to 550 million and would choose Anantapur for the power generation.
Usually, Photo Voltaic (PV) technology is used for utilizing solar energy in production of electricity. However, MEIL choose to go for Parabolic Trough Technology as it was costing less compared to the PV technology in 2010. Over the years, as PV technology matured, cost of the technology came down drastically.
“However, in the future cost of this CSP will also come down,” Uma Maheshwar said.