Wind energy: TN govt sets ambitious target, but industry players are less sure

With the Tamil Nadu government planning to support the repowering of old windmills, major private players are also making significant investments in new wind farm projects in the state.

The repowering and new private projects together are expected to boost the state’s total wind energy production by an additional 25 per cent. But wind power generators are less confident about the ambitious increase projected by the Tamil Nadu government.

Repowering involves replacing older turbines with new, high-capacity ones, or retrofitting them with more efficient components. The aim is to significantly increase wind farm production and extend wind farm life.

Soaring demand for power

According to the latest data from the Union Power Ministry, Tamil Nadu has the highest power demand among the southern states.

As the state focuses on expanding its manufacturing sector and signing deals to attract new industries for growth and employment, its power demands have grown substantially.

The government expects that wind farms set up by private players, along with new substations, will attract medium-scale industrialists to purchase as few as one or two windmills to meet their power needs.

These initiatives, combined with repowering projects, are anticipated to help the state achieve its ambitious target of generating 500 MW of wind power by 2030. Tamil Nadu’s conventional power capacity stands at 15,839.56 MW, while the total installed capacity of renewable energy is 36,563.27 MW.

Wind power remains a major contributor to the renewable energy sector. With an installed capacity of 10,591.68 MW, the state generates 13,000 MW of wind power annually.

Cost of windmills

Setting up a 1 MW windmill costs around Rs 7 crore for the developers. The Tamil Nadu government believes this investment is not affordable for MSMEs (micro, small and medium enterprises). 

However, when big private players handle the investment, installation and maintenance of windmills, MSMEs can purchase windmills and benefit from maintenance facilities in a more cost-effective manner.

Tamil Nadu Energy Department officials told The Federal that companies like JSW, Everrenew, Green Infra, Velliyanai and Amplus Iru are currently establishing wind farms.

Private players

These developers aim to open their farms to MSMEs and integrate them into their operations.

‘’JSW, for instance, has proposed to supply 38 MW to Salem Steel Plant. Other private players are also preparing to launch their projects soon. Meanwhile, the National Institute of Wind Energy is exploring new windy sites suitable for wind farms,” said one official.

Currently, wind production is concentrated in Muppandal in Kanyakumari, the Palghat Pass near Coimbatore and the Sengottai Pass near Tenkasi.

These three major passes experience strong winds at speeds of 8-12 metres per second. "Identifying new sites could attract further developers to the state," said the official.

Testing ground

Tamil Nadu, a pioneer in the wind energy sector, has become a testing ground for repowering methods.

This initiative began with the power reforms report by economist Arvind Subramanian, who suggested new policies related to renewable energy, including repowering and life extension of old windmills.

Nearly 76 per cent of windmills in Tamil Nadu are used for captive consumption (power utilised by generators within their industries like spinning mills and foundries). Other private wind farm projects aim to attract power-intensive industries and medium enterprises.

The Federal spoke with K Venkatchalam, chief advisor of the Tamil Nadu Spinning Mills Association (TASMA), who highlighted the technical challenges in repowering and starting new private wind farm projects.

The state government's incentives — such as special interest loans and reduced open access charges — are necessary for windmill owners to undertake repowering projects, he said.

Association’s concerns

“We are pleased that the government aims to increase wind generation by 25 per cent. However, repowering and life extension of old windmills alone may not significantly boost production,” Venkatchalam said.

“Wind availability, machinery and grid connectivity are major challenges. We have suggested a wind-solar hybrid setup as a partial solution. Yet, given the current situation, many are hesitant to invest without incentives due to financial challenges and an unsuitable climate for new investments,” he added.

He also pointed out that Gujarat, which surpassed Tamil Nadu in wind power generation two years ago, attracts investors with low open access charges.

Grid facilities

Experts like Ajay Devaraj, Secretary General of the Indian Wind Power Association, have identified curtailment issues and the need for improved grid facilities as significant concerns for executing repowering projects.

Wind energy curtailment is the reduction of a wind farm's energy production below its maximum generation capacity. This is initiated for reasons such as transmission or operational constraints, congestion in transmission or distribution networks, and inaccurate output predictions. 

“Many old windmills may not receive new spare parts since their manufacturers are no longer in the market. Even if windmill owners place orders, manufacturers might need at least two years to design and produce the new parts,” he said.

“Consequently, we might only see a 5 to 8 per cent increase in repowered windmills, which makes achieving the 25 per cent target a challenging goal,” said Devaraj.

Regulatory, technical factors

Previous issues with curtailment for grid stability have been addressed, and pooling stations should be strengthened to handle increased generation, he noted.

The main constraints for installing new wind turbines include regulatory and technical factors. There are norms governing the distances between turbines, wind farms and nearby roads or dwellings.

The presence of numerous overhead electricity lines also poses a challenge for turbine placement, as newer turbines are taller than the older models.

Active old windmills

When The Federal shared the concerns raised by various associations, government authorities said curtailment issues have been resolved, and concerns about repowering can be addressed. Windmill owners who cannot participate in repowering can opt for refurbishment, they said.

''We have an option for active old windmills. We could provide life extension certificate for wind turbines. It could be obtained based on the assessment by certified agencies and with certification charges. We have not stopped the banking facility for old windmills,” said an official who did not wish to be named.