UPDATE 1-Aker Energy to buy Ghana unit of Hess, expects first oil in 2021

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OSLO, Feb 19 (Reuters) - Aker Energy AS, controlled by Norwegian billionaire Kjell Inge Roekke, has agreed to buy Hess Corporation's Ghana unit in a $100 million deal and plans to launch production from its first oilfield there in 2021, it said on Monday.

Aker Energy aims to build a significant exploration and production business in the country together with the Ghana National Petroleum Corporation (GNPC), it added.

Aker ASA, Roekke's main listed investment vehicle, owns 50 percent of Aker Energy, while TRG, his privately held holding company, owns the remaining 50 percent.

The transaction gives Aker Energy a 50 percent stake in the deepwater Tano Cape Three Points block, which holds an estimated 550 million barrels of oil equivalents in contingent resources and potential for a further 400 million barrels, it said.

"The Tano Basin offshore Ghana is a prolific petroleum region where Aker Energy sees considerable potential to apply the Aker Group's experience from the Norwegian Continental Shelf," it said.

In 2017, another Aker group company, Aker BP, bought the Norwegian assets of Hess in a $2 billion transaction. (Reporting by Terje Solsvik, editing by Louise Heavens and Jason Neely)