CHENNAI: Could renewable energy along with battery-based energy storage in Tamil Nadu be cost competitive compared to new coal-powered plants? A study by Climate Trends and JMK Research and Analytics states that renewable energy with battery storage in the State could help reduce curtailment of renewable energy.
A chunk of solar power in Tamil Nadu was curtailed since the lockdown. Similarly, curtailment of wind power in 2019 went up to 3.5 hours per day from 1.87 hours per day in 2018, says the study. “Our analysis found that the cost of hybrid renewable energy with a battery storage system is on a par with new coal power plants in Tamil Nadu. Moreover, in 10 years, incremental capacity addition would further drive down the cost by over 31 per cent,” said Jyoti Gulia, founder of JMK Research and Analysis.
The analysis, released by Climate Trends and JMK Research and Analytics, tracks the system from an initial capacity of 800MW of solar and 200MW of wind along with 500MWh of storage, that would cater to Tamil Nadu’s average annual power demand for two hours per day from 2021-2023. Its capacity is augmented to three hours of daily backup for 2024-2026, and then four hours per day for 2027-2030. In the last year, the hybrid system would meet 29 per cent of Tamil Nadu’s average annual power demand at a competitive levelised cost of Rs 3.4/kWh.
It also puts into perspective that TN has five thermal power projects in the pipeline over the next three years. The Cheyyur ultra mega coal power plant is the biggest of these, with a tariff of Rs 5-6/kWh, which would be 32-43 per cent more expensive than the system modelled in the analysis, says the study.
However, the economic feasibility of the lithium-ion-based battery energy storage system has been questioned by experts. National Institute of Wind Energy Director General Dr K Balaraman said the technology is evolving in Australia but is not economically viable. “The cost is around Rs 5-6/kWh and if one takes into consideration the life of the battery, which could be two-to-three years, it is not economically feasible as one has to again invest in the battery,” said Dr Balaraman.
He added that only if there is a technological breakthrough in battery storage would it be feasible. When Express contacted a State government official, he said the technology is new and one has to study it before trying it out.