Revenue Code of 1986 is amended by adding at the end the following new paragraph: (12) Source of municipal solid waste feedstock In the case of a qualified facility that produces electricity both from municipal solid waste and other solid waste that is not a qualified energy resource— (A) such facility shall be considered a qualified facility if it otherwise meets the requirements of subsection (d), and (B) subsection (a) shall only apply to that portion of the electricity produced from municipal solid waste. . (c) Effective date The amendments made by this section shall apply to taxable years beginning after the date of the enactment of this Act.