UPDATE 1-Thai Glow plans long-term bonds this month

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BANGKOK, May 8 (Reuters) - Thai power producer Glow Energy PCL GLOW.BK will sell bonds in two tranches worth up to 6 billion baht ($189 million) to fund the construction of a power plant and other projects, fund managers said on Thursday.

The bonds, rated "A" by Thailand's TRIS Rating, would be divided into 7- and 10-year maturities and be offered to institutional and cash-rich investors later this month, two fund managers, who declined to be identified, told Reuters.

"The firm has an initial plan to sell 3 billion baht, but the amount has yet to be finalised," one of the fund managers said, adding it had scheduled book-building for May 22.

Glow has proposed to sell up to 6 billion baht of bonds guaranteed by its small power producer subsidiaries, TRIS said in a statement.

The bonds will be underwritten by Kasikornbank KBAN.BK.

Glow, majority owned by French utility Suez SA (LYOE.PA), produces and supplies electricity, steam and water to customers in the Map Ta Phut industrial estate in the eastern province of Rayong and nearby.

The firm said in December it would spend about 40 billion baht to build a 660-MW coal-fired power plant and construction was expected to start in the middle of 2008.

At 0326 GMT, Glow shares were down 1.5 percent at 33.50 baht, while the main Thai index .SETI was down 0.08 percent.

Benchmark seven-year government bonds were yielding 4.54 percent in the secondary market at 0303 GMT and ten-year bonds were yielding 4.78 percent. ($1=31.80 Baht) (Reporting by Arada Therdthammakun; Editing by Alan Raybould)