The ESB has sold its stake in the Marchwood Power Limited to German insurance firm Munich Re.
The firm had a 50% shareholding in the facility, which is located in Southampton in England, along with Scottish energy provider SSE.
The sale was carried out after the Government asked the ESB to raise a €400 million dividend through the sale of non-strategic assets.
The company said the sale had been completed following a “very robust sales process”, which was managed by Macquarie Capital.
The price paid for was described as competitive, however no further details were released.