Energy Northwest is gingerly wading back into the waters of nuclear energy. The Richland, Wash.-based not-for-profit “joint operating agency,” which supplies electricity at cost to its 25-member public utilities in Washington state, is the renamed Washington Public Supply System, which made history in 1983 with the largest municipal-bond default ever when it walked away from $2.25 billion in bonds issued to construct five nuclear powerplants. The agency now is cautiously polling its customer utilities about their interest in a new nuclear plant to come online between 2017 and 2020. The utility is considering a plant composed of six 45-MW light-water reactor modules with passive safety features.