HONG KONG/SINGAPORE, June 12 (Reuters) - Asian renewable energy platform Athein is seeking to raise between $250 million and $300 million in equity from investors to fund its planned solar and wind projects in India, the Philippines, and Vietnam, the company's CEO told Reuters Monday.

Milan Koev, Athein's chief executive based in Singapore, said the company seeks $1 billion in total over the next five years, to fund the 2.5 gigawatt-peak (GWp) pipeline of projects.

The rest will take the form of debt, while Athein has hired Hong Kong-based Green Horizon Capital Partners to advise on the equity raise, Koev said in an interview.

He said the company was starting with three countries where it has a pipeline of projects, all solar, except for one wind project in Vietnam.

"Going forward, we may look into a couple of other interesting markets," Koev said. "We're paying attention to Indonesia and Thailand, Australia."

Uptake of renewable power is rising quickly in India and Southeast Asian nations as their booming economies grapple with power cuts due to a weak power grid and climate change that is increasing demand for air conditioning and focusing attention on the need for green power.

The Paris-based International Energy Agency last month predicted investment in clean energy globally would extend its lead over spending on fossil fuels this year.

The equity raise is the first by Athein in a joint venture with five solar companies, Koev said.

Michiel Prompers, managing partner at Green Horizon, said the adviser has launched the process of the equity raise and started gauging interest from infrastructure funds, private equity funds and strategic investors.

He said non-binding offers were expected within the next month and the aim was to close the equity raise by the end of the third quarter.

Reporting by Kane Wu in Hong Kong and Yantoultra Ngui in Singapore; editing by Barbara Lewis

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