New England's supplier of liquefied natural gas fuel to power plants continues to search for immediate ways to replace essential LNG shipments that were canceled because of terrorist attacks on a pipeline in south Yemen in March and April. The disruption of LNG deliveries to Distrigas' terminal in Everett, Mass., adds a new edge to the quandary of how to meet New England's growing reliance on gas for electricity generation, an official of the North American Reliability Corp. said.