Vistra 

Vistra Corp. is one of the largest power producers and retail energy providers in the US. It owns 44 gigawatts of generation capacity, including natural gas (27 GW), nuclear (6.5 GW), coal (8.7 GW), and solar and battery storage (1.3 GW). The Cogentrix acquisition will add 5.5 GW of gas generation. Vistra's retail electricity business serves 5 million customers in 20 states, including almost a third of all Texas electricity consumers. Vistra emerged from the Energy Future Holdings bankruptcy as a stand-alone entity in 2016.