The main purpose of this legislation is to update the Clean Air Act to recognize fuel used by ocean-going vessels as a type of renewable fuel. This change aims to allow the generation of credits under the renewable fuel program for this specific type of fuel, promoting cleaner energy options in maritime transportation. Key provisions of the legislation include an amendment to the existing definition of renewable fuel in the Clean Air Act. It adds fuel for ocean-going vessels to the list of fuels that can qualify for renewable fuel credits.