Coal linkages to supercritical power projects on priority basis

The Ministry of Power is looking to clear swiftly coal linkages for projects based on supercritical technology, said sources.According to top officials in the government, supercritical power projects would get linkages to coal mines on a priority basis, compared to projects based on sub-critical technology."We are looking to encourage supercritical technology and planning initiatives for that," H S Brahma, secretary, Ministry of Power, told Business Standard. He, however, did not confirm the story.The government is already planning to increase the presence of supercritical power generation in the country. According to the Central Electricity Authority, India is constructing 38 supercritical units, some of which to be commissioned during the Eleventh Five Year Plan period. About 60 per cent of the thermal power generation capacity in the Twelfth Plan period could come from supercritical technology. For the Thirteenth Plan, the entire coal-based capacity is expected to be on supercritical technology.Industry experts said the government plans to exceed its target of supercritical-technology-based power in the Eleventh Plan itself, which is why it is offering these incentives."Fuel is the most critical part of the value chain. This is a method of advertising supercritical technology to power companies," said Hitul Gutka, analyst, India Infoline.

NTPC, which is using this technology, recently floated a tender for a 660 Mw unit of supercritical equipment. L&T, too, said it plans to use this technology for its 5,000 Mw capacity. Besides, all the ultra mega power projects are based on supercritical technology.The move to make coal linkages available easily would encourage smaller companies to embrace this technology. "The constraint for smaller players is financing," said Gutka.Supercritical power projects incur higher capital costs than sub-critical technology, but experts say the benefits in the long-run are high."Supercritical power plants produce higher levels of heat rate and reduce fuel consumption. Carbon emissions are less and coal handling and ash handling equipment size small. The plant load factor is also better in supercritical technology," said Rupesh Sankhe, analyst, Angel Broking.Experts believe this would send a positive signal to investors and enterpreneurs in the sector, which is dogged by coal shortages. "There is a risk for power producers in terms of coal shortages. Next year there could be coal shortage to the tune of 45-50 million tonnes," said Sankhe.

What is supercritical technology?

Conventional coal-fired power plants, which make water boil to generate steam that activates a turbine, have efficiency of about 32%. Supercritical power plants operate at temperatures and pressures

above the critical point of water, i.e. above the temperature and pressure at which the liquid and gas phases of water coexist in equilibrium. This results in higher efficiencies – above 45%. Supercritical power plants require less coal per megawatt-hour, leading to lower emissions (including CO2 and mercury), higher efficiency and lower fuel costs per megawatt.