UPDATE 2-U.S. Coast Guard assists drifting Mass. LNG tanker

(Recasts, updates status of tanker, adds details, changes dateline from NEW YORK)

BOSTON Feb 12 (Reuters) - A tanker filled with liquefied natural gas that broke down in heavy seas off Cape Cod in Massachusetts has restored some electrical power and is being towed by two tug boats, the U.S. Coast Guard said on Tuesday.

The 933-foot Catalunya Spirit is about 33 miles (53 km) east of the town of Chatham and is being towed northwesterly at about four miles-per-hour (6 kph), parallel to shore, the Coast Guard said in a statement.

The tanker's operator, Teekay Corp (TK.N), contracted the tugboats and other help shortly after the Catalunya Spirit lost power on early Monday morning and went adrift in 12-ft (3.7 meter) waves and 40 mph (64 kph) winds off Chatham.

By 5 p.m. EST, full power had not been restored, the Coast Guard said, adding that it had not sustained structural damage or leaked any of its natural gas.

The tanker, which was headed to Boston from Trinidad, would be towed to an anchorage point off the Massachusetts port of Gloucester for repairs, it added.

The Boston Herald newspaper reported that a suspected computer failure was to blame for the loss of propulsion in the 93,450-tonne vessel.

Teekay public affairs manager Jonathan Anthony said the company was working with technicians who had been flown to the vessel to get it restarted.

SUEZ LNG NA unit Distrigas of Massachusetts LLC owns and operates the import and regasification facility located along the Mystic River in Everett, Massachusetts.

The Everett terminal has been operating longer than any other LNG import terminal in the United States.

Between 1971 and 2003 it received approximately half of the LNG imported into the country. The facility currently meets approximately 20 percent of New England's annual gas demand, with storage satisfying an additional 15 percent of the region's peak gas demand, according to the company's Web site.

The terminal is home to two LNG storage tanks with a combined capacity of 3.4 billion cubic feet, or 42 million gallons, and installed vaporization capacity of approximately 1 bcf per day. Sustainable daily throughput capacity is approximately 715 million cubic feet per day. (Reporting by Eileen Moustakis in New York and Jason Szep in Boston; Editing by David Gregorio)