National Low-Carbon Fuel Standard Act of 2007

National Low-Carbon Fuel Standard Act of 2007 - Amends the Clean Air Act to revise the renewable fuel standard for FY2009-FY2012. Directs the Administrator of the Environmental Protection Agency (EPA) to: (1) establish a fuel emission baseline; (2) identify qualifying low-carbon transportation fuels; (3) establish a low-carbon fuel certification and marketing process; and (4) require each obligated party to reduce the average lifecycle greenhouse gas (GHG) emissions per unit of energy of the aggregate quantity of fuels introduced into commerce to specified levels by not later than January 1, 2010, through the use of low-carbon fuels and improvements in the production of conventional fuels.

Requires the average lifecycle GHG emissions of the aggregate quantity for 2012 to be at least 3% below the 2007 average should emission limitation regulations not be promulgated.

Authorizes an obligated party to apply to the Administrator to receive a temporary suspension of the requirement to comply with such regulations if events outside of the control of the party could lead or have led to disruptions in the transportation fuel supply.

Permits obligated parties to receive credits for achieving greater reductions in lifecycle GHG emission of the fuel produced, distributed, or imported than are required.

Requires the Administrator to ensure that fuel sold or introduced into commerce in the United States (except in noncontiguous states or territories) contains, on an annual average basis, at least the specified volume of ultra-low carbon fuel for 2012-2025. Prohibits such regulations from restricting geographic areas in which low-carbon transportation fuel and ultra-low carbon fuel may be used or from imposing any per-gallon obligation for the use of those fuels. Sets forth a minimum applicable volume for 2026 and thereafter.

Requires the Administrator of the Energy Information Administration to provide to the EPA Administrator an estimate of the volumes of conventional fuels projected to be sold or introduced into commerce. Requires the EPA Administrator to determine the fuel obligations based on such an estimate.

Requires regulations concerning ultra-low carbon fuel to provide for the generation of specified credits by obligated parties.

Authorizes the EPA Administrator, on the receipt of a petition of one or more states, to waive ultra-low carbon regulations by reducing the national quantity of Category I or Category II ultra-low carbon fuel in the conventional transportation fuel pool if it is determined that: (1) implementation of the regulations would severely harm the economy or environment; or (2) there is an inadequate domestic supply of such fuel.

Considers 1 gallon of cellulosic biomass ethanol or waste derived ethanol to be the equivalent of 2.5 gallons of renewable fuel through 2017 (currently there is no time limit).

Requires the Administrator to establish: (1) a carbon intensity number and a green index number as part of the renewable identification number program; and (2) a set of standards to minimize the negative environmental impacts of an increase in the volume of fuels required by such Act and to ensure long term resource sustainability from the sourcing and production of low-carbon fuels.