The state-run power major National Thermal Power Corporation (NTPC) today said it will invest about 40,000 crore rupees for setting up three coal-based projects in Madhya Pradesh in the next 5 to 6 years. <br/><br/>Speaking to reporters on the sidelines of a power ministers' conference in New Delhi, NTPC Chairman and Managing Director R S Sharma said these projects of over 7,960 Mega Watts capacity would be constructed at Bamitha, Gadarwara and Khargaone in the state. He said studies such as environmental impact, water and fuel availability are underway and would be complete in the next six months. Mr Sharma said within one year work will start on these projects.