Fig. 4 presents the breakeven price of switchgrass as a function
of days in storage using the linear DIS parameter estimates
for the net and net plus film methods (equation (2)). Net
was more profitable than net and film at prices beneath the
breakeven price line. The value of DM losses averted with
increased protection was insufficient to cover the extra cost of
the film in reducing DM losses for a given price and storage
period. Conversely, net and film was more profitable than net
for prices above the breakeven price line. The value of DM
losses avoided at higher prices and longer storage periods was
greater than the added cost of protection using the film. For
example, if the switchgrass price was $60 Mg1 and baseline
costs of net and film were used, then using net was more
profitable than net and film for any storage period less than
148 days. After 148 days in storage, wrapping the bales with
net and film would be preferred if the price of switchgrass
price was $60 Mg1. The protective cover cost sensitivity analysis indicated that if the price of the net increased 25%,
the storage period necessary for the extra protection to be
profitable increased in length. Net and film would be preferred
to net for switchgrass stored more than 195 days if the price
was $60 Mg1. If the price of the film decreased 25%, net would
be preferred to net and film for switchgrass stored up to 102
days given a switchgrass price of $60 Mg1.