State-owned NLC India, which operates lignite-based thermal power plants, is looking to invest big in renewable energy. The current lignite reserves of 28.31 billion tonnes at its Neyveli base in Tamil Nadu are not expected to last beyond 30-40 years.
The company's chairman and managing director, Sarat Kumar Acharya told India's Economic Times: "Producing power only from lignite is not sustainable in the long run, although generation from this fuel will continue to be the bulk of (NLC's) revenue for years to come."
NLC recently won a 709MW solar project in Tamil Nadu. It plans to have 1.5GW in renewables generating capacity by next year and around 4.2GW by 2020, made up of around 4GW of solar and 207MW of wind projects. The company plans to finance all these projects from internal accruals.
Another big private power producer, Adani Power, is planning to invest in about 150MW of wind projects at its Mundra thermal power plant in Gujarat.
Mundra has a large private port and a generation capacity of 4.2GW, using imported coal. An increase in the price of imported coal had made the firm's fixed-supply contracts prices unviable, and it recently discontinued supplying nearly 1.25GW to the grid.
Interestingly, the company sees the wind investment as a combined power-generation initiative.
According to the project report for the wind farm, "this would be one of the world's first 'combo' generation power plants, combining wind with thermal generation and would be a trailblazer for a new business model of power generation: wind power combined with super critical technology to benefit the environment like never before."
The wind project, planned along the coastal belt close to the Mundra port, is also a part of the Indian shipping ministry's initiative of greening all major Indian ports.
The Adani group is not new to the wind sector. In April 2016, it announced its foray into wind power production with 70MW of capacity in Andhra Pradesh and Madhya Pradesh.
The group's renewable-energy subsidiary, Adani Green Power, was also among the winners of India's first reverse auction, under which it won a contract to supply 50MW of capacity at a record-low tariff of INR 3.46/kWh ($0.054/kWh).
While conventional businesses investing more in wind power is nothing new, the clear pointer in these two cases is that the tide is turning in favour of wind because of serious sustainability concerns.