"NTPC REL, a wholly-owned subsidiary of NGEL which in turn is a subsidiary of NTPC Limited, received Letter of Acceptance for 500 MW RE-RTC power from REMCL," it said. The capacity has been won in a competitive bidding process for a total 900 MW RE-RTC on offer, NTPC said, adding a power purchase agreement (PPA) will be signed with Indian Railways for 25 years.