Japanese electronics giant Hitachi is to buy the nuclear power project Horizon, which includes a plan to build a new plant on Anglesey.
Hitachi says between five and six thousand jobs could be created during construction and a thousand permanent posts when it's up and running. It says that'll be in the first half of the 2020.
The Wylfa power station was due to close in 2014. The Anglesey site's Reactor 2 shut down in April.
Today, the announcement has been hailed as a boost to the area.
– CARWYN JONES AM, FIRST MINISTER
This is very good news for Wales and the UK. The potential benefits of a new nuclear development on Anglesey would be substantial - not just in creating thousands of highly skilled jobs and boosting the supply chain - but in helping to secure our energy supply in the future.
We will continue to work closely with the UK Government and with Hitachi to secure this investment for Wales.
On Twitter, the Welsh Secretary, David Jones, has said the news is "terrific" for Anglesey.
Terrific news for the people of Anglesey: #Wylfa purchased by Hitachi
The #Wylfa deal will mean up to 6,000 construction and 1,000 long-term jobs, as well as making a huge contribution to UK energy security
Hitachi making strong commitment to UK supply chain. About 60% of value of first plant to be UK-sourced #Wylfa