‘Forecasting’ is the only answer to TN’s wind industry problems

Tamil Nadu, a State that pioneered wind power generation in the country and is still a clear leader in terms of installed capacity, seems to have had enough of it.

The State has 7,200 MW of windmills, but capacity addition has been coming down, and might not exceed a couple of hundred MW in the current year, a far cry from the 1,086 MW seen in 2011-12.

Reason: the State does not want wind power any more. Wind power companies whine about tacit discouragement by the authorities, chiefly by the State-owned generation and distribution company, Tangedco. Tangedco refused to buy electricity from the wind farms in the State last year, causing huge losses to them (Rs 100 crore, according to one estimate.)

While most people are upset with Tangedco, some point out that the discom has its own issues. First, there are not enough transmission lines to evacuate wind power, to remedy which some work is under way, albeit slowly.

Second, windmills generate power also during low-demand times, such as during nights, when Tangedco will make a loss if it buys wind power. Third, wind companies are allowed to put their electricity into the grid and claim it back (after paying charges) another time within the year. When they want it back, Tangedco has to buy power from the market and supply them — often at a high price.

With such issues, Tangedco has been signalling implicitly that it does not want more windmills in the State.

Even those who set up windmills for consuming the power themselves (“captives”) are disadvantaged because during the ‘power cut’ hours they cannot use their own electricity, as the transmission infrastructure cannot operate for them alone.

Then, has Tamil Nadu’s wind power story come to an end?

It need not be so, say industry insiders.

Most of these problems can be solved by proper ‘scheduling and forecasting,’ says Madhusudhan Khemka, Managing Director of Regen Powertech, a wind turbine manufacturer, and the Chairman of Indian Wind Turbine Manufacturers’ Association (IWTMA).

‘Scheduling and forecasting’ helps predict how much electricity a power producer will generate at a given slice of time the following day. Doing this calls for special equipment and expertise.

Since last July, the Central Electricity Regulatory Commission has required wind companies to predict how much they will generate during each 15 minute interval the following day. CERC has been collecting data but has refrained from penalising the generators.

Now the industry is realising that ‘scheduling and forecasting’ is actually good, as it helps answer the main criticism against wind power —fickleness. The problem is this: when the wind blows power from a 1,000 MW zips into the grid, and a few minutes later it is all gone when the wind stops — it makes life difficult for an electricity distribution utility.

But knowing when the windmills will generate electricity and when it will not, will help. PP Gupta, Managing Director, Techno Electric, a company that has a large wind farm in Tamil Nadu also feels that ‘scheduling and forecasting’ would address some of Tangedco’s issues.

The issue has now boiled down to who should do it. Khemka and Gupta are among those of the view that generation prediction is best done by the ‘load despatch centre’ in each State — SLDC — entities that route power. The industry is prepared to buy the equipment and pay for the services, says Khemka. “We can run the SLDC itself,” says Gupta.

Others, such as Vishal Pandya, whose renewable energy consultancy, REConnect, also manages ‘scheduling and forecasting’ for about 600 MW of wind capacity in several States, feel that SLDC may not be the answer. Issues such as disagreement over data, and ‘who will pay any penalties — generators or SLDC’ will crop up.

“The industry is willing to discuss these issues,” says Khemka.

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