Ice-creams and dairy products major, Hatsun Agro, will soon be purchasing a rather unusual production input: steam.
A German company called Protarget has put up a parabolic trough system next to Hatsun’s ice-cream factory near Salem, in western Tamil Nadu, which will produce 400 kg of steam an hour, using sun’s heat. The steam is piped to the ice-cream plant where it is used for pasteurising milk.
The system, like any regular solar thermal system, works by the parabolic mirrors concentrating the sunlight onto a tube that carries a ‘heat transfer fluid’ which gets heated up quickly. The heat is then transferred in a heat exchanger to water, which becomes steam. In solar thermal plants that produce electricity, this steam is used to drive the turbines.
Though quite a few steam-sale deals have happened in the country — companies like Thermax have done steam contracting deals, where buyer pays only for the steam — Hatsun-Protarget deal is different because the steam is made with solar energy.
Hatsun, which till now has been using steam produced in-house by burning coal, is spending more on solar steam. Company officials told BusinessLine that it would pay ₹1.3 a kg of steam, 20 paise more than the cost it currently incurs. But it doesn’t mind paying more because of its commitment to renewables.
Hatsun has also put up a solar-water heater system, which produces hot water for its operations, mainly for cleaning its tanks, on the roof of its ice-cream plant in Salem. Dr C Palaniappan, Managing Director of Sun Best, which sold the system to Hatsun, said that the plant cost ₹1 crore, but Hatsun could avail itself of a subsidy of ₹42 lakh from the Ministry of New and Renewable Energy. The cost to Hatsun would be paid back in four years, while the life of the 220 units of solar heat collectors is 20 years, Palaniappan, a solar energy expert, said.
The collectors produce 32,000 litres of hot water, which is 87 degrees hot when it reaches Hatsun’s plant. With both steam and hot water produced from sun’s energy, Hatsun actually produces “solar ice-cream,” said Palaniappan.