The three plants will contribute about 90 Giga Watt hours (millions of units) of energy a year, or about one percent of total demand.
Each plant had cost 2.4 billion rupees, the power ministry said.
One plant was built in Daluwa, Nirmalapura coast by Nirmalapura Windpower (Pvt) Ltd.
The second plant was near an existing coal plant in Kalpitiya built by Daily Life Renewable (Pvt) Ltd. It had eight wind turbines on 85 meter tall towers. The third 10MW plant bordering a lagoon in Sethapola was built by Powergen Lanka (Pvt) Ltd. It had seven towers 65 meters high.