NEW YORK (AP) ¿ Greek shipping company Tsakos Energy Navigation Ltd. said Tuesday it will generate at least $15.5 million from a two-year charter extension on a tanker.

The shipping company didn't identify the oil company that extended its use of the Pentathlon, a seven-year-old double hull suezmax tanker.

Tsakos said the gross-revenue figure assumed only a minimum payment rate, but suggested it would get a higher rate when the extension begins in early November.

Tsakos said it was the third extension in a row with the same major oil company since 2003.

Tsakos operates 47 double-hull vessels with five more ships expected to be delivered through 2011.

U.S.-traded Tsakos shares rose 12 cents to $16.12 in midday trading.
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