eia MENU Natural Gas Weekly Update Summary of recent natural gas market activity Today in Energy Posted September 18,2020 U.S. nuclear capacity outages were 35% higher in summer 2020 than 2019 U.S. nuclear capacity outages averaged 4.2 gigawatts (GW) during the summer of 2020 (June through August), nearly 35% higher than the 2.7 GW average in summer 2019. Summer nuclear outages were at their lowest level from late June to mid-July, averaging 2.3 GW: