Due to coal shortage for thermal plants in the country, government is considering to allow use of importyed coal up to 30% with certain changes in boiler design.
UNION POWER ministry is considering allowing increase in the blending ratio of imported coal from 10 to 30 percent at thermal plants across the country in view of domestic coal shortage.
There are 82 thermal plants in the country and 24 of these thermal plants have coal stock of less than 7 days. Government has asked various power utilities to import the coal to meet coal shortages.
The total coal demand in the country for 2011-12 has been estimated as 713.24 million tones (MT), whereas the indigenous availability is envisaged at 591.78 MT, leaving a huge deficit of 121.46 MT. Power utilities have been asked to import 35 million tones of coal in the current financial year.Power utilities have been, so far, able to import only 10.171 MT, as of August 2010, leaving a balance of 24.829 MT to be imported during the remaining seven months. The use of imported coal is limited to about 10 percent of the coal used to fuel Indian boilers, due to its relatively higher slogging. Moreover certain components in the imported coal tend to corrode boiler parts and emit more smoke when used with Indian designs.NTPC has found that the Dadri 4x210 MW Stage I boilers are not amenable to the use of imported coal in more than a 10-15% blending ratio. At Kahalgaon Stage-I, 4 units of 210 MW, each are amenable to this increased dosage, due to the presence of an operational Gas Recirculation (GR) system.Government has asked Bharat Heavy Electricals Limited to incorporate suitable modifications to its power plant designs to allow the greater use of imported coal.NTPC’s 1500 MW Jhajjar thermal plant has coal linkage from Mahanadi coal field mines in Orissa. The coal quality of Mahanadi coalfield mines is of “F” grade with useful heat value of 2400 to 3360. NTPC has worked out gross calorific value of coal at 3034. The designed requirement of boilers is 3500 GCV and to meet this requirements NTPC will blend the Indian coal with 15 percent imported coal of 6000 GCV.NTPC-against the target of 13.9 MT of coal imports for 2010-11, the utility has already imported 6.649 MT, during the first five months of the yearThe 1200 MW Hissar thermal plant is being built with Chinese equipment and the boilers have been designed for 4000 GCV coal in order to reduce the boiler size. The coal linkage for the thermal plant is also with Mahanadi Coalfield mines in Orissa supplying only “F” grade coal. To meet the design specifications the imported coal is required to blend in higher percentage. The cost of imported coal is around 6000 per MT against Indian coal cost of around 2500 per MT .The use of imported coal would raise the generation cost by more than one rupee per unit.Haryana has been given an annual target of 1.45 million tones (MT) of imports for the current financial year whereas HPGCL has imported only 0.079 MT during the first five months of the year.