The UK's 550 MW Dungeness B-21 nuclear unit came back online at 2.30 am (0130 GMT) Sunday as planned, operator EDF Energy said in a REMIT note.
EDF Energy took the unit offline on May 17 for a planned refueling outage.
Any delays to the unit's return would have impacted balance of summer and potentially winter prices, traders said on May 17.
The Dungeness nuclear power plant in Kent, southern England, has two units totaling 1.05 GW and an estimated decommissioning date of 2028.
