India’s coal-fired power capacity may hardly grow over the next decade despite plans to build new plants as older facilities that cannot meet new environmental guidelines face closure.

The nation may need to scrap about 40 gigawatts (GW) of thermal capacity that cannot be modernised to meet emission targets, according to Central Electricity Authority Chairman Ravindra Kumar Verma.

Bloomberg newsagency reports that is roughly equivalent to the amount of coal-fired power CEA expects to be installed by 2027, though more may need to be built if more older plants than expected cannot be upgraded.

“They are really old plants and there is no space to retrofit them,” Mr Verma said in an interview with Bloomberg at his office in New Delhi.

“If the number of non-compliant plants exceeds current estimates, then 10GW to 12GW of new coal may have to be requisitioned.”

The possible closure would reinforce the country’s commitment to battling climate change.

It would also challenge criticism of India’s coal production goals levelled by United States President Donald Trump after he pulled his country out of the United Nations sponsored Paris Agreement on climate change.

Prime Minister Narendra Modi has set the world’s largest renewable energy target after China, while the country’s power minister Piyush Goyal said that renewable energy capacity would overtake coal-fired power by 2022.

“It’s a substantial improvement leading to lower coal consumption and reduction of the carbon footprint,” said Kameswara Rao, the Hyderabad-based leader for energy, utilities and mining at the Indian division of PricewaterhouseCoopers.

“It is also an opportune time to shut some plants as there is sufficient supply available,” he added.

The country expects to produce surplus power for existing customers in 2017 for the first time in at least 13 years amid slowing demand-growth.

Bloomberg reports the nation plans to raise the share of power from non-fossil fuel sources to 40 per cent by 2030 as part of its climate commitments.

CEA’s Mr Verma expects India to increase total generation capacity to 515GW by 2022 from the current 329GW, mostly with the addition of renewable capacity.

India’s proposed emissions regulations would require existing coal-fired plants with a combined capacity of 112GW to install flue-gas desulphurisation, or FGD, equipment to reduce sulphur emissions.

India unveiled its first-ever standards for particulate matter, sulphur dioxide and nitrogen oxides from thermal power plants in December 2015.

The rules, which are among the most stringent in the world, would increase the cost of coal power generation by nine per cent, according to a May 19 Bloomberg New Energy Finance (BNEF) research note.

The cost of energy from emissions-compliant coal power plants would increase to US$60 a megawatt-hour, compared with new solar power at US$38 a megawatt-hour and wind tariffs at US$54 a megawatt-hour, it said.

“India may continue to keep building new coal power plants, albeit at a much slower rate than in the past, to meet its growing base-load power requirements,” the BNEF report said.