State regulators approved the construction of a third major natural gas pipeline Thursday that will increase Florida's capacity by 20 percent at a cost of $3 billion.The unanimous vote by the five-member state Public Service Commission clears the first of two major hurdles for the new system that is projected to come on line in 2017."The need for this project is indisputable at this time," said Commissioner Julie Brown. Added Commissioner Eduardo Balbis: "I believe this is a good project. Having a third pipeline coming into the state, we're going to mitigate interruption. We have two existing pipelines at or near capacity."The project still must receive approval by Federal Energy Regulatory Commission. The new pipeline, which would run from Alabama through the heart of the Florida peninsula, would enable the state to tap more of the nation's growing shale gas sources.In July, Florida Power & Light, which proposed the project, picked Houston-based Spectra Energy to build the new pipeline. Other natural gas users such as Duke Energy Florida and Tampa Electric also could tap the new pipeline.FPL says the current capacity is fully contracted and the new line is needed to accommodate the growing demand in the state for natural gas.FPL opened a 1,250-megawatt natural gas plant in Cape Canaveral in June and is constructing two identical plants in Riviera Beach and Port Everglades."Today was an important, positive step forward," said Sarah Gatewood, an FPL spokeswoman. She said the federal review will prove more complex as work to identify the exact corridor for the pipeline continues.Duke Energy wants to construct a 1,600-megawatt natural gas plant by mid 2018 to replace the broken, shuttered Crystal River nuclear plant. Duke also wants to build another natural gas facility by mid 2020.Almost 68 percent of the state's electric generation in 2012 came from natural gas. Florida receives most of its natural gas from two pipeline companies, Florida Gas Transmission, whose line runs across the Panhandle down to Miami-Dade County, and Gulfstream Natural Gas, whose line flows from Mobile Bay, Ala., across the Gulf of Mexico, to Manatee County.In addition to adding 465 miles of new interstate pipeline, the project also would connect the new line, called the Sabal Trail Transmission, to the other two major lines. Florida Gas Transmission and Gulfstream currently are not connected.NextEra Energy, FPL's parent company, plans to spend $550 million to connect all three major lines.The public can review proposed routes for the pipeline projects during open houses scheduled in November for the connection project and in December for the new Sabal Trail Transmission line.Ivan Penn can be reached at [email protected] or (727) 892-2332.