Bengaluru: A Chinese company that had expressed interest in a solar auction conducted by NTPC pulled out, while India’s Tata Power, Azure Power and O2 Power won projects of 300 MW-400 MW each, with the lowest tariff being Rs 2.43 per unit.Sungrow, which also makes inverters, had put in a bid for 300 MW, although it did not quote a tariff. The reason for its last-minute withdrawal was not clear. Tension between India and China may have been a factor, a person aware of the matter said.“Either they were disqualified or they were told not to participate. Otherwise, the government may not have gone ahead with the tender,” the person said.Queries to NTPC remained unanswered at the time of going to press. This was the first time Sungrow sought to bid for an Indian solar power project.The biggest winners in the auction were O2 Power, Azure Power and Tata Power. They won capacities of 400 MW, 300 MW and 370 MW respectively. The lowest winning tariff was Rs 2.43 per unit. The remaining 100 MW was won by Canadian developer AMP Energy at Rs 2.44 per unit.Solar tariffs had fallen to a record low of Rs 2.36 per unit last month in an auction conducted by the Solar Energy Corporation of India, the renewable energy ministry’s nodal agency for conducting wind and solar auctions.India recently extended safeguard duty on solar equipment from China for another year. Imposition of basic customs duty on such equipment is also in the works, officials said.