The Tema Oil Refinery plans shutting down its 45,000 barrel per day crude distillation unit (CDU) for maintenance in the first week of July.
Speaking in an interview with Reuters, the Managing Director of TOR, Mr Kofi Sarpong, said: "We have programmed one week of maintenance this year on some specific equipment that will be in July. The CDU will be closed."
TOR, which comprises the CDU and a 14,000 barrel per day catalytic cracker, meets 80 to 85 percent of Ghana's oil product demand.
Last year, the cracker was shut for 10 weeks for routine maintenance while the CDU was also shut for four weeks for routine works.
Poor rainfall pattern has affected power distribution nationwide.
But these power cuts have had very little impact on Tema, which generates 80 percent of its own power, said Sarpong.
Further repairs of existing generators should mean that Tema will be able to generate all its own power by the middle of next year, he said.
Little progress has been made in the oft-touted plans for privatisation and expansion of the refinery, under which Tema would be able to meet all Ghana's needs and capture a larger share of the West African fuels market.
"It is a combined privatisation and expansion. Very soon, the government will appoint a transaction adviser," Sarpong said.
Last year, Ghana approached two South Korean companies, SK Corp and Samsung Corp to discuss the sale of a stake in the refinery.
West Africa's refined petrol products needs are met by imports and a handful of regional oil refineries.