In the tiny Tamil Nadu village of Muppandal in the Western Ghats, truck drivers and travellers routinely stop at the shrine of Isaikki Amman, offering money and food to the deity for having afforded them safe passage over the dangerous mountain highway.

Legend has it that the wind at the Muppandal pass is so menacing, it has been known to overturn two-wheelers – and occasionally larger vehicles.

But the gusty winds rising from the Arabian Sea are also an economic opportunity. Since 1986, Muppandal has housed India’s largest operational onshore wind farm calculated by installed capacity. With a capacity of 1,500 MW, the state-developed Muppandal Wind Farm was pivotal in raising the energy capacity of not just Tamil Nadu but the entire country.

However, for the past two decades, experts have been complaining that the facility that once was the crown jewel in India’s renewable energy enterprise has been losing its sheen. A visit to the establishment reveals the sight of rusting turbines, broken towers and outdated wind-generation components.

The shrine of the shrine of Isaikki Amman. Credit: Vasudevan Sridharan

Of the 175 GW of power that India aims to harness from a bouquet of non-fossil energy sources such as solar, bio, and small-hydro power by 2022, about 35% is intended come from wind. To achieve this, modernising existing installations such as the Muppandal Wind Farm will be key.

Conversations with more than 40 people involved with the sector including policymakers, industry experts, landowners, researchers in think tanks, green energy proponents and maintenance staff, shows that in Tamil Nadu, the majority of ageing wind turbines require “repowering” – a significant upgrade to their infrastructure.

Yet, few had a clear idea about who should shoulder the burden of the repowering process or how it could be financed.

The wind farms are owned by a mosaic of scores of owners, from small-time farmers to wealthy individuals to business houses. While some of the power generated is utilised by the owners, Tamil Nadu’s state-run utility purchases the bulk of the supply.

Significant potential

In 2020, the electricity generated by the state’s wind farms accounted for 13% of the state’s total power requirement – though they have the potential to have generated 31% of Tamil Nadu’s requirements. The output is purchased by the Tamil Nadu Generation and Distribution Corporation Limited or Tangedco – the government-run entity responsible for power generation, transmission and distribution.

Besides running its own generating stations, Tangedco procures power from private entities under fixed contracts after signing private power purchase agreements with them.

While the landowners of wind farms complain that the prices for electricity is not lucrative enough and have not been suitably increased, there is no financial incentive for them to modernise their installations. Further, many small-time owners do not have the necessary capital to repower.

Tamil Nadu has an installed wind power capacity of 9.2 GW though it has the potential to generate 68.75 GW, said DV Giri, Secretary-General of the Indian Wind Turbine Manufacturers Association.

“Since the inception of wind turbine movement started in Tamil Nadu [in the late ’80s and early ’90s], more than 3000 MW of turbines [over one-third of total installations] have completed the end of their lifetime and are ready for repowering,” said Giri. “Though the government of Tamil Nadu has talked about repowering in the past, things are yet to take off.”

Credit: Vasudevan Sridharan

Tamil Nadu’s landscapes are well suited for generating solar and wind power.Thanks to the governmental policies and incentives, Tamil Nadu capitalised on these assets, becoming both a pioneer and leader in the wind energy sector.

As of October, Tamil Nadu was India’s leader in wind energy in terms of installed capacity: it houses about about 25% of the country’s total wind energy capacity. Gujarat was second, with installed capacity of 8,952 MW. States like Karnataka and Maharashtra have been narrowing the gap in recent years even as Tamil Nadu’s wind energy capacity has been stagnating.

Twenty years ago, power-intensive industries like textile and cement took advantage of the government’s incentives to set up wind power units to meet their own demand. Today, 40% of the state’s wind farms are owned by the textile industry.

As a consequence of this push, dozens of renewable energy think tanks, research institutes, equipment manufacturers, and such related entities are clustered around Chennai.

Old technology

The bulk of Tamil Nadu’s turbines were installed 20 years ago and some well before that, experts say. The spinning systems of older models have limitations – they cannot capture low or high winds. Most can work only with constant winds.

The planned load factor for ageing turbines – industry parlance for the ratio between actual and potential output – is well below 20%. Even as the latest turbines come with a planned load factor of 45%, which is considered a healthy yield across the world.

However, due to an increasing focus on solar energy, the lack of wind-sector-specific policy initiatives and the high cost, the repowering process for wind energy has not been a priority in Tamil Nadu.

Bharath Jairaj, who heads India’s energy division at the global non-profit research organisation World Research Institute, estimated that if systems in Tamil Nadu are upgraded, output could be increased four or five times the current capacity.

However, it isn’t quite clear how this overhaul could be financed.

Credit: Vasudevan Sridharan

The Central government as well as those in the states should frame a mixture of carrot-and-stick policies to modernise outdated installations and processes, and attract private investment, industry experts suggest.

“There is not much policy intervention from the government to take on repowering,” said Francis Jayasurya, India Director of the Global Wind Energy Council. “To compare, older cars are regularly phased out for more efficient and energy-saving ones in the automobile industry. This is not happening here.”

He added: “Only the government should step in. They should tell the owners ‘boss, the land and turbine may belong to you. But power is a national subject. You are a hindrance now. You are not being progressive.’”

Others hold similar views.

“One way to deal with this is the utility must take a firm stand and disconnect the turbines once the power purchase agreements end after 20-25 years,” said N Ramani, an advisor at Suzlon, a wind turbine manufacturer. “So, there will be some pressure. It is not an incentive but a penalty. There are occasions where a 20-year agreement is extended for 20 more years after the deal’s expiry.”

Speeding up payments

For new investors to be interested, policymakers should iron out payment delays from utilities and boost the capacity of power transmission networks, said Ramani. Payments are now delayed by 18 months to two years, he said, “and they are not very remunerative as well”.

Tangedco’s debt to power producers stood at over Rs 13,000 crore until April. It costs the debt-ridden Tangedco between Rs 4.50 and Rs 6 to generate a unit of power from its own facilities while it pays Rs 3.51 per unit to the wind energy generators under long-term agreements.

Said Ramani: “The utility is unclear on what it wants to do. It is not clear whether the owners will be allowed to sell the extra energy they would generate.”

Amid a wider global push for environment-friendly energy sources like wind, the repowering of older turbines should be among the top priorities, experts say.

“This untapped potential is a loss for the state and the country,” said Jayasurya. “This [repowering] is a low-hanging fruit.”

Vasudevan Sridharan is an independent journalist based in South India.

This story was produced with the support of Internews’ Earth Journalism Network.