by Vijay Jayaraj
Tamil Nadu, India’s southernmost state, is regarded by some as the renewable energy capital of India. It’s also getting to be known for expensive electricity.
The presence of highly windy regions makes the state an ideal place for wind farms. But despite the year 2022 being one the best for wind generation, the state utility here had to increase its prices.
“The new rate for those using 500 units bimonthly would be $20 against the old rate of $13,” reported a news article, which addressed the recent hike in electricity charges and the shock waves to consumers.
The government has said that the hike in this year’s power prices is to compensate for the $ 1.5 billion debt incurred by the state utility over the last decade. The state has one of the highest gross domestic products in India and boasts a wide range of industries that buy electricity from the state utility. Yet, the power generator has incurred such a high debt. Why is that?
We know from examples in Germany and California that additions of wind and solar power into the main grid inevitably increases the cost of power to consumers. This happens for various reasons.
Power generated from wind and solar is intermittent. Days with clouds or without wind – or with too much wind – result in volatility or no generation. Solar does not function at night. Industries that I personally visited have reported frequent repairs to machinery damaged by fluctuations in a power supply highly reliant on wind farms.
Though it is technically possible for utilities to keep backup energy sources readily available, doing so costs a lot. Instead, the utility regularly buys power from other states as a backup.
“The problem with thermal generation (fed by fuels such as coal) is that you cannot switch it on and off instantly,” says an officer from state utility. “It takes several hours for any plant to light up the boiler after shutdown. It also increases the wear and tear of these plants, adding to the cost since these plants are designed only for a stable load. So, it is always advisable to have these plants running at some technical minimum. Our experience is that it is not technically feasible to keep running them at very low capacity utilization.”
He adds that despite sophisticated forecasting models, the state utility “can’t predict the unexpected increase or decrease in wind energy generation. That really creates a problem for us in terms of grid management.”
Further, most of the wind turbines in the state are old, inefficient and are too expensive to replace. So, the utility has technological dinosaurs that have exceeded their design life of 20 years. There are over 3,000 wind turbines with less than one megawatt (MW) capacity each and a capacity utilization factor of just 10-14 percent, compared to the high-capacity utilization factor of 50 percent for the state’s coal plants.
Officials in charge of generating the power have become more pragmatic and say that an increase in wind installations no longer means a reduction in the use of coal power. As a result, state authorities have new coal plants in the pipeline and have asked the federal government to designate more coal mines as exclusive suppliers to electricity generators.
Tamil Nadu already has 2,440 MW of nuclear generation and plans to increase that to more than 6,000 MW. The state takes advantage of its scenic mountain region’s water resources with hydroelectric stations.
Green ambitions of western elites have increased energy costs and undermined reliability across the globe, and developing countries are vulnerable to the same influences.
However, if Tamil Nadu policy makers can avoid being inundated by the green wave, they have a good chance of increasing reliable power generation from stable sources like coal and nuclear.