Procurement of Alternative or Synthetic Fuels under 42 U.S.C. § 17142 says that agencies are not to enter into procurement contracts for an alternative or synthetic fuel (other than for research or testing) unless the contract specifies that the life cycle greenhouse gas emissions associated with the production and combustion of the fuel is less than or equal to emissions from an equivalent conventional fuel.
No Federal agency shall enter into a contract for procurement of an alternative or synthetic fuel, including a fuel produced from nonconventional petroleum sources, for any mobility-related use, other than for research or testing, unless the contract specifies that the life cycle greenhouse gas emissions associated with the production and combustion of the fuel supplied under the contract must, on an ongoing basis, be less than or equal to such emissions from the equivalent conventional fuel produced from conventional petroleum sources.