How small can a viable rural ethanol production site be? The final section of the 1978-1980 collection of case studies projected fuel ethanol production from corn on a family-run farm in the Midwest. The cost calculations were very different, however, because there was already a working market for fuel alcohol — and a known price ($1.74/gallon in Iowa, November 1979). Using this figure,[47] a net operat­ing profit of total revenues could be projected for the first year of operation, ignoring factors such as finished goods and work-in-process inventories that would reduce the actual production cost of ethanol (table 5.4).

property taxes). Also designed for farm-scale use in South Dakota, a solid-state fer­mentation process (chapter 4, section 4.6.2) using sweet sorghum as the feedstock and upscaled to produce in principle 83 l of 95% ethanol/hr was predicted to have produc­tion costs of $1.80/gallon; the single largest contributor (61%) to production costs was that of the sorghum feedstock.15