With natural gas prices climbing as well, wind turbines have become attractive to Indian business. The Essar Group of Mumbai, a big industrial conglomerate active in shipping, steel and construction, is now working on plans for a wind farm near Chennai, formerly Madras, after concluding that regulatory changes in India have made it financially attractive.

“The mechanisms didn’t used to be there; now they are,” said Jose Numpeli, vice president for operations at Essar Power. The electricity boards “know how to cost it, they know how to pay for it.”

Roughly 70 percent of the demand for wind turbines in India comes from industrial users seeking alternatives to relying on the grid, said Tulsi R. Tanti, Suzlon’s managing director. The rest of the purchases are made by a small group of wealthy families in India, for whom the tax breaks for wind turbines are attractive.

Wind will remain competitive as long as the price of crude oil remains above $40 a barrel, Mr. Tanti estimated. To remain cost-effective below $40 a barrel, wind energy may require subsidies, or possibly carbon-based taxes on oil and other fossil fuels.

Mr. Tanti and his three younger brothers were running a textile business in Gujarat, in northwestern India, when they purchased a German wind turbine — only to find that they could not keep it running. So they decided to build and maintain turbines themselves, starting Suzlon in 1995 and later leaving the textile business.

To minimize land costs, wind farms are typically in rural areas, chosen for the strength of the wind there as well as low prices for land. But that can mean culture shock.

“There were no big changes until the turbines came,” Mr. Patil said, pausing from plowing here with his father in this remote, hilly, tribal area 200 miles northeast of Mumbai, where oxen remain at the center of farm life and motorized vehicles are uncommon.