The government has estimated a capital expenditure of Rs 88 lakh to Rs 1.28 crore per megawatt for retrofitting the old plant to meet new emission norms.
"The ministry is not in favour of retrofitting the old plants and wants to use supercritical technology. The ministry has a policy for not going for retrofitting over 25-year old plants," an official said.
The official further said, "The government does not want to continue with old technology... Besides environmental cost, they are less energy efficient."
Singh also told the House that the capital expenditure on retrofitting old plants to comply with new norms will be up to Rs 1.28 crore per megawatt.
The Ministry of Environment, Forest and Climate Change had issued revised environment norms on December 7, 2015. The ministry had given two years time period to meet these norm which already lapsed last month.