UPDATE 2-Vessel exits Maryland Cove Point LNG export terminal -shipping data

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March 2 (Reuters) - The Gemmata liquefied natural gas tanker left Dominion Energy Inc's Cove Point LNG export facility in Maryland early Friday, likely carrying the first export cargo from the facility, according to Reuters shipping data and energy traders.

Officials at Dominion were not immediately available for comment.

When the Gemmata, a Royal Dutch Shell Plc vessel, docked at Cove Point earlier this week, analysts said it would likely be the first to pick up fuel from the facility since the tanker came from Spain - a non-LNG exporting country - with less than a full cargo.

Dominion has spent about $4 billion to add export facilities at Cove Point, long an LNG import terminal on Chesapeake Bay.

Another vessel, the Methane Spirit, is also headed for Cove Point, according to Reuters shipping data. Methane Spirit is located near Singapore and is expected to reach Cove Point around March 31.

Cove Point is the second big LNG export terminal in the lower 48 U.S. states after Cheniere Energy Inc's Sabine Pass terminal in Louisiana, which exported its first cargo in February 2016.

After decades of importing massive amounts of gas, the United States became an exporter of the fuel in 2017 for the first time in 60 years due to record U.S. natural gas production from shale fields.

The United States is expected to become the world's third- biggest LNG exporter by capacity by the end of 2018 with output expected to grow to 10.1 billion cubic feet per day (bcfd) by the end of 2020 from 3.0 bcfd today.

Cove Point is designed to liquefy about 0.75 bcfd of gas. One bcfd can power about 5 million homes.

In December, Dominion said Shell would take the initial LNG cargoes from Cove Point.

The shipping data does not say where Gemmata is heading, noting it is available for orders.

Dominion sold the project's capacity for 20 years to a subsidiary of GAIL (India) Ltd and to ST Cove Point, a joint venture of units of Japanese trading company Sumitomo Corp and Tokyo Gas Co Ltd.

Some of the LNG going to ST Cove Point will go to Tokyo Gas and some will go to Kansai Electric Power Co Inc, according to Sumitomo's Pacific Summit Energy (PSE) unit.

(Reporting by Scott DiSavino Editing by Chizu Nomiyama and Bernadette Baum)