The first ship carrying liquefied natural gas for export departed Dominion Energy's mutli-billion dollar facility in Cove Point last week, the company said.The company did not say where the ship was headed.Liquefied natural gas is a cooled version of natural gas that can be transported long distances. The Cove Point plant is designed to produce 8.3 million gallons of the fuel per day.The facility cost $4 billion to construct and building work began in 2014. The project was opposed by environmental groups.The gas is being provided by Shell. Ultimately, the plant is contracted to serve a joint venture between two Japanese firms and the American subsidiary of an Indian company.