Chennai:India's nuclear sector regulator has given the nod for the second 1,000 MW unit at Kudankulam in Tamil Nadu to go critical/start fission process, said an industry official. "The permission to NPCIL (Nuclear Power Corp of India Ltd) has been given so that the Kudankulam second unit can go critical," the official Said preferring anonymity. A senior official of NPCIL also confirmed the receipt of AERB clearance and added that THE date of unit going critical/start of fission process had not yet decided. India's atomic power plant operator NPCIL is setting up two 1,000 MW atomic power plants at Kudankulam in Tirunelvelli district, around 650 km from here, at an outlay of over Rs 17,000 crore. NPCIL had earlier said the second unit would go critical this month. The first unit attained criticality, which is the beginning of the fission process, in July 2013. Subsequently it was connected to the southern grid in October 2013. However, commercial power generation began only on December 31, 2014. The unit also experienced several breakdowns after commercial production started. Operating at full capacity, the unit supplies power to Tamil Nadu (562.5 MW), Puducherry (33.5 MW), Kerala (133 MW), Karnataka (221 MW) and Andhra Pradesh (50 MW). Currently the first unit is generating over 900 MW daily. Once the second unit at Kudankulam goes critical, the total atomic power capacity in Tamil Nadu would go up to 2,440 MW. Already NPCIL has two 220 MW units at Kalkpakkam near here under its Madras Atomic Power Station. Another 500 MW of nuclear power is also expected to be added soon by India's fast breeder reactor company Bharatiya Nabhikiya Vidyut Nigam Ltd when its prototype fast breeder reactor (PFBR) starts nuclear fission process.