UPDATE 1-California will soon be using Indonesian LNG

(Adds Sempra confirmation of cargo by September)

NEW YORK, July 2 (Reuters) - Energy consumers in California will soon be using Indonesian natural gas after the start-up of the Tangguh liquefied natural gas project in the Southeast Asian country this week.

Sempra Energy (SRE.N: Quote, Profile, Research) expects to import LNG from Tangguh to its Costa Azul import terminal in Baja California in northern Mexico by the end of September, a company spokesman said Thursday.

Sempra secured 500 billion cubic feet of LNG from Tangguh for 20 years under a deal signed in 2004, and the project start-up this week paves the way for deliveries to North America.

"We expect cargoes from Tangguh to start arriving [to Costa Azul] this quarter," Sempra spokesman Art Larson said.

Tangguh's first LNG cargo is expected to be shipped to South Korea this week, followed soon after by a Sempra cargo to Costa Azul.

Steve Johnson, president of Waterborne Energy in Houston, which monitors the global flow of LNG, said he reckons a cargo will arrive "in August at the latest."

The Costa Azul terminal, with the capacity to import 1 billion cubic feet per day of LNG, has not taken a cargo since September. The terminal, which began operations in May last year, supplies gas to the southwest U.S. market.

LNG is natural gas cooled to liquid for shipment across seas in specially designed tankers. Once at a receiving terminal, it is regasified for transport ashore through pipelines. (Reporting by Edward McAllister; Editing by John Picinich)