Tasley is a single-unit industrial gas turbine that began commercial operation in 1972.  Calpine acquired Tasley in 2010 as part of its purchase of the Conectiv Energy assets.  It is black-start capable, meaning that in an emergency if the whole grid system goes down (causing a blackout), the self-sufficient unit can be used to bring the system back online.  Tasley can be started without needing a feed from a larger unit and, in turn, can feed the power needed by larger units to restart after a blackout.