Windmill replacement up against hurdles

The central government's plan of repowering 5 gigawatt (GW) of old windmills and new wind capacity addition of 18-20 GW every year from now onwards to reach 150 GW to meet the 500 GW renewable target by 2030 is likely to face many challenges -- such as non-availability of turbines, site related challenges, the management of dismantled turbines and even raw material availability, say industry experts.

As of 22 November 2022, India's wind energy capacity was 41.8 GW and only 1.45 GW of wind capacity was added in 2021. The highest capacity addition in recent years was in FY17 when the country added 5.5 GW.

Sources say since 2017, local demand declined due to the introduction of e-reverse auctions or projects awarded based on the lowest bidding to boost competition and also due to the non-availability of high-speed wind sites to start projects. But that backfired as many bidders refrained from bidding for unviable projects. The lowest tariff discovered in wind energy auctions in 2022 was ₹2.84 ($0.036)/kWh. The projects will be viable only if tariffs are around ₹3.3-₹3.5 per unit and above, say sources.

That had forced many multinational wind manufacturers like GE Renewable Energy, Siemens Gamesa, Vestas and Enercon to use their Indian facilities for exports to global markets. Sources say for most global wind majors, now making in India is cheap, almost 60% lower than their home bases in Europe or US. If a technician in Europe has to be paid 40-50 euros per hour (₹3,220- ₹4,150), a technician of the same skill and quality is available in India for one-fourth of that cost. Further, net zero goals are driving global wind markets, where corporations are investing heavily in new projects. If local demand suddenly increases, many of these companies will have to add new capacities as international markets will also see high demand for turbines.

Companies with sizeable domestic demand which are actively focussing on India are local players Suzlon and Inox Wind and Chinese companies Envision and Zenvion, formerly with REpower, say sources.

The draft wind energy policy says most of the wind turbines installed in India up to the year 2000 are of sub 1 MW capacity and are at sites having high wind energy potential. Some of the old wind turbines have already completed their design life while some are approaching the end of their design life. These are not only inefficient in comparison to the latest technology but also have lower hub heights (in the range of 30- 60m) in comparison to hub heights of 120-140 m range being installed these days. The government estimates 25406 MW of installed wind capacity in the country is 2MW and below, which can be replaced with 3MW and above onshore machines. In this direction, the Government came up with a draft repowering policy that may help to have new installations of 5 GW and attract an investment of over ₹40,000 crore in the next few years.

But repowering with higher machines has many hurdles. One prime issue to be addressed is how the country is going to deal with discarded machines, which is an environmental issue. Many old machines have gearboxes, which use oil and seeping this oil into the ground is an issue.

Another is windmills are located in hubs and land is owned by different companies. Right of way and dismantling may face issues and legal battles from neighbours, as all may not be interested in investing in new machines. Besides, new machines will have large and long blades of above 100 meters and transportation of these machines from factories in the hinterland to sites far away will be a big challenge.

Raw materials for machines also can be an issue. Take the case of blades, which weighs about 20 tonnes. Over 65% of the blade is glass and resin and carbon fibre are used to make this intricately complex product, a mesh of complex technology. Many parts for the machines are imported and the current capacity is about 1,50,000 MW to meet the requirement for large capacity addition, special glass and related capacity needs to be doubled, say sources.