15 USC 3391a – “Essential agricultural use” defined
For the purposes of section 3391 of this title, the term “essential agricultural use” shall—
(1) include use of natural gas in sugar refining for production of alcohol;
(2) include use of natural gas for agricultural production on set-aside acreage or acreage diverted from the production of a commodity (as provided under the Agricultural Act of 1949 [7 U.S.C. 1421 et seq.]) to be devoted to the production of any commodity for conversion into alcohol or hydrocarbons for use as motor fuel or other fuels; and
(3) for the 5-year period beginning on June 30, 1980, include use of natural gas in the distillation of fuel-grade alcohol from food grains or other biomass by facilities in existence on June 30, 1980, which do not have the installed capability to burn coal lawfully.