TerraPower and PacifiCorp, the nuclear developer and electric utility aiming to build a first-of-its-kind facility at a retiring Wyoming coal plant before the end of the decade, announced plans Thursday to consider adding up to five more of the same design in PacifiCorp’s service territory by 2035.

PacifiCorp — parent company of Rocky Mountain Power and Pacific Power — supplies power to customers in six states: Wyoming, Utah, Idaho, Oregon, Washington and California. But TerraPower is eyeing Wyoming and Utah, in particular, as it looks to commercialize Natrium, its sodium-cooled reactor.