GenOn Energy, Inc., based in Houston, Texas, United States, was an energy company that provided electricity to wholesale customers in the United States. The company was one of the largest independent power producers in the nation with more than 14,000 megawatts of power generation capacity across the United States using natural gas, fuel oil and coal. GenOn Energy is headquartered in the Reliant Energy Plaza in Downtown Houston. The company, formerly known as RRI Energy, acquired Mirant on December 3, 2010. The corporate names and logos of both RRI Energy and Mirant were retired. NRG Energy completed its acquisition of GenOn Energy in December 2012 for $1.7 billion. GenOns stock ceased trading and was exchanged for NRG stock. The company was originally known as Houston Industries (NYSE: HOU), and Houston Lighting & Power was its subsidiary. In August 1996 HI closed on a merger with NorAm Energy Corp, a natural gas utility. The combined company, as of 1997, had assets of $18 billion and annual revenues of about $9 billion. By November 1997 there was a published report stating that the company wished to acquire Central & South West Corp. HI declined to comment.