Construction of Nuclear Power Corp of India Ltd's (NPCIL) Kakrapara plant's fourth unit, scheduled to start commercial generation this year, has not been completed and is running more than a year late, a government memo showed.
"The Unit #4 is under construction and would reach completion by March, 2024," a power ministry memo dated May 10 seen by Reuters on Tuesday quoted Bhuwan Chandra Pathak, chairman of state-run NPCIL, as saying.
The 700 MW unit in western Gujarat state had been scheduled to start commercial operation this fiscal year ending March 2023, according to a 2022 power ministry report. The delay could add to strain on some old coal-fired utilities and potentially delay their retirement.
The federal power ministry and NPCIL did not immediately respond to a request seeking comment.
The Kakrapara setback is negative for India's efforts to keep carbon dioxide emissions in check, as solar power cannot address rising night-time electricity demand due to higher air-conditioning use.
Coal-fired power plants have cranked up output to the highest levels in years, resulting in more emissions, to address higher night-time demand and due to a slowdown in the addition of new round-the-clock power sources including nuclear.
Nuclear power contributes barely 3 per cent of India's electricity capacity and the sector has been hobbled by lack of foreign investment and opposition from critics over safety issues.
The heavy water reactors in the third and fourth units of the Kakrapara plant were developed by scientists working for the Indian government.
The third unit of the Kakrapara plant, connected to the grid in January, would be able to produce at full capacity only by October/November 2022 as "design validation was in progress" and due to "safety issues," Pathak told the power ministry.
"NPCIL was advised to expeditiously complete the commissioning while keeping into account all the safety considerations," the power ministry said in the memo.
Power ministry data showed India's installed capacity of nuclear power plants has remained stagnant for at least five years.
Coal-fired capacity has grown 4 per cent and hydro by 5 per cent in the last five years, while additions of renewable energy doubled amid a push for cleaner air.