News: AWC UPDATE 1-Alcoa reverts to gas for fuelling alumina refineries in Western Australia

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Jan 12 (Reuters) - Alcoa Corp AA.N said on Thursday it reverted to using gas to fuel boilers at its partially owned Kwinana and Pinjarra alumina refineries in Western Australia, a week after the aluminium producer had resorted to using diesel due to gas shortage.

Gas supply shortage in Western Australia has forced Alcoa to flag a 30% cut in its production from its Kwinana refinery, which it jointly owns with Alumina Ltd (AWC) .

"Kwinana refinery continues to operate with one production unit offline and reduced process flows," Alcoa said. However, Alcoa did not set out a timeline on when it will resume full production.

Chevron Corp CVX.N on Wednesday re-commenced gas supply from Wheatstone domestic gas plant to the Western Australia market after an equipment failure knocked off the energy firm's 215 terajoules-a-day Wheatstone plant on Jan. 5.

The Wheatstone outage came on top of a supply loss from Santos Ltd's (STO) Varanus Island operation, which has been shut since late-November due to a leak on a gas pipeline from an offshore platform.

Despite increased gas supply into the Western Australian domestic gas market, Santos continued to experience production constraints at two gas facilities, Alcoa said.