(Adds company comment)
June 21 (Reuters) - Delfin LNG LLC asked U.S. federal energy regulators for a three-year and six-month extension until March 28, 2023 to build facilities proposed to connect floating liquefied natural gas (FLNG) vessels off the coast of Louisiana:
* The U.S. Federal Energy Regulatory Commission (FERC) issued an order on Sept. 28, 2017 authorizing Delfin to build and operate the facilities to transport and deliver natural gas to FLNG vessels in federal waters off Cameron Parish in Louisiana.
* The FERC order required Delfin to complete the facilities within two years of the order date.
* Officials at Delfin said in an email that the company is targeting a final investment decision to build the project at the end of 2019 that would enable the facility to produce first LNG in 2023.
* Since FERC issued the order, Delfin said in its filing that it "has worked diligently to further its development of the project."
* "Due to the detailed nature of the engineering design of the offshore facilities, which includes floating liquefaction technology, and the complexity of developing the necessary commercial arrangements, progress on the project, including the onshore facilities, has been slower than originally anticipated," Delfin said.
* In March, the company said plans to construct the FLNG vessel in China, which may also provide funding and buy part of its output, were moving ahead despite trade tension between the countries.
* The Delfin LNG project is designed to produce up to 13 million tonnes per annum (mtpa) of LNG or about 1.7 billion cubic feet per day (bcfd) of natural gas. One billion cubic feet is enough gas to supply about 5 million U.S. homes for a day.
(Reporting by Scott DiSavino Editing by James Dalgleish)