Entergy is planning to refuel the 680MW Pilgrim nuclear power station in the US state of Massachusetts next year, as it intends to remain in operation for another three years.
The planned refuelling in early 2017 will allow the power plant to continue supplying energy to New England. The company plans to cease operations at the facility on 31 May 2019.
Entergy said that the decision to cease operations at Pilgrim narrows previously announced shutdown timeframe of 2017-19.
Pilgrim nuclear power station site vice-president John Dent said: "Another benefit of the three-year window before shutdown is that Pilgrim will continue to be a good neighbour, providing economic benefits and charitable donations. In just the past four years, Pilgrim has donated more than $1.5m to local, regional and statewide non-profit organisations."
Refuelling outages in 2015 resulted in a $70m investment in the plant, including $25m in new equipment.
Nearly 2,000 employees, including 1,184 extra contract workers, performed hundreds of activities during last year's outage, the company said.
The company will form a dedicated team of individuals to plan decommissioning of the power plant.
The team will develop a 'Post-Shutdown Decommissioning Activities Repor't describing planned decommissioning activities, a schedule, cost estimate, and environmental impacts.
Pilgrim nuclear power station began generating electricity in 1972. The carbon-free electricity generated at the facility is enough to power more than 600,000 homes.
Entergy is involved in electric power production and retail distribution operations. It delivers electricity to 2.8 million utility customers in Arkansas, Louisiana, Mississippi and Texas.
The company owns and operates power plants with approximately 30,000MW of electric generating capacity, including nearly 10,000MW of nuclear power.