ST. FRANCISVILLE — Entergy said Tuesday that a St. Francisville nuclear power plant's generating unit was out for "several days" before a widespread outage that left 100,000 without power in New Orleans over the weekend.

According to an Entergy spokesperson, River Bend Station's status was taken into account when the company made power available to the Midcontinent Independent System Operator when the outage happened Sunday.

Entergy added that MISO entered its "load shed directive" during the outage, which is a last resort protocol that "helps prevent more extensive and prolonged power outages that could severely affect the reliability of the power grid for weeks or even months." Load shed temporarily interrupts the delivery of electricity to maintain the integrity of an electrical grid.

"Several factors can lead to load shedding, including extreme weather, sharply increased electric demand, unplanned generation plant outages, transmission constraints, unexpected damage to equipment, unavailability of purchased power or a combination of these situations," Entergy explains on its website.

In regards to Sunday's outage, which was affected by the outage at River Bend and a scheduled outage at Waterford 3 in Killona on the west bank of St. Charles Parish, Entergy said its models "did not show the need for load shed."

"MISO uses a different model and has a broader view of system conditions, which MISO is able to see due to its status as the regional transmission coordinator. Entergy had been monitoring load conditions due to warmer than typical weather, but as noted, its models did not show the need for load shed," the power company said.

MISO manages the electrical grid in portions of 15 states, including Louisiana in the South and Midwest, and parts of Canada.