witchgrass fields.
Totally 42 harvest units are used and operate at their full capacities
through the harvesting season except for July at 279,520 dry
tons/month. Totally 259 million gallons of biofuel are produced,
which yields a total profit of 89 million dollars and a unit profit
of $0.34/gallon. As shown in Table 2, this biofuel unit profit is higher
than that for the configuration in Section 3.2 ($0.32/gallon) because
the two biorefineries operate at their full capacities and
consequently the fixed costs are shared by more produced biofuel.
Moreover, more switchgrass is available in the nearby fields; that
results in a lower transportation cost. One the other hand, this unit
profit is slightly lower than that for the configuration in Section
3.3.1 ($0.35/gallon) because the portion of cheap stalk and straw
in the mixture of multiple types of feedstocks is lower than that
for the configuration in Sectio