TOKYO - Japan's biggest power generator JERA said on Monday it will invest $1.58 billion to take 27% stake in Aboitiz Power Corp in the Philippines from Aboitiz's parent company to boost its presence in the country where power demand is growing.

The deal marks the biggest investment by JERA, a joint venture between Tokyo Electric Power Company Holdings Inc and Chubu Electric Power Co Inc, and is also aimed at expanding its renewable power portfolio, it said.

"We want to provide the Philippines' company with our know-how that we have accumulated over the decades on how to improve the efficiency of operations and maintenance and work together to achieve both growth and decarbonisation," JERA President Satoshi Onoda told a news conference.

Power demand in the Philippines is expected to grow at an average annual rate of 4.2% through 2030, making the development of electric power infrastructure an urgent priority, he said.

"There is no liquefied natural gas (LNG) power plant in Philippines yet, but our involvement will enable Aboitiz to develop a world-class LNG power plant with competitive fuel procurement and efficient operation," he said.

Aboitiz Power, which is controlled by Aboitiz Equity Ventures Inc, aims to double power generation capacity to 9.2 gigawatts(GW) by 2030 from 4.6 GW now by expanding renewable energy and developing gas-fired power plant to meet increasing demand of electricity, Onoda said.

JERA and Aboitiz will explore collaboration in many areas including operation and maintenance, development of power projects, fuel procurement and use of cleaner fuels such as ammonia and hydrogen.

Aboitiz is eyeing to build a LNG power plant of about 1 GW which will use about 600,000-700,000 tonnes of LNG annually, according to Onoda.

"No concrete plan for a LNG plant has been set yet, but we will study together about the power project and the best way to procure the fuel," he said.

(Reporting by Yuka Obayashi; editing by David Evans) ((Yuka.Obayashi@thomsonreuters.com; +813-4520-1265;))