NRG Energy, Inc. is an American energy company, headquartered in Houston, Texas. It was formerly the wholesale arm of Northern States Power Company (NSP), which became Xcel Energy, but became independent in 2000. NRG Energy is involved in energy generation and retail electricity. Their portfolio includes natural gas generation, coal generation, oil generation, nuclear generation, wind generation, utility scale generation, and distributed solar generation. NRG serves 6 million retai NRG Energy ...