Citrus Energy LLC, Boca Raton, is one of the eight organizations awarded a grant. The company plans to use the $2.5 million to build an ethanol bio-refinery that uses citrus waste to produce 4 million gallons of clean, affordable, locally produced ethanol per year. The facility should be up and running within a year, says Thomas Stender, vice president of business development
According to the company, Florida produces 5 million tons of citrus waste a year. Historically, this waste has been dried into citrus pulp pellets and fed to cattle. This act requires a large capital investment by the processor with a negative return on investment, according to the company. Citrus Energy also says that Florida does not have a suitable climate for corn production, thus requiring an alternative source from which to produce ethanol.
Instead, Citrus Energy plans to convert citrus waste from some of the state’s growers into cellulosic ethanol, which differs from the conventional form of ethanol most often derived from corn. Cellulosic ethanol is produced from plant stems and stalks, as well as from wood chips, switchgrass and even corn stover. Conventional ethanol can be produced only from the plant’s sugar and starches. The two types of ethanol yield the same amount of energy per gallon—about two-thirds that of gasoline, and perform the same in automobiles. However, Citrus Energy says that citrus waste can be used to produce cellulosic ethanol at significantly lower production costs than conventional ethanol produced from corn. And with Florida’s large supply of citrus waste, cellulosic ethanol production seems to be the state’s best option.
The ratio of the amount of energy it takes to produce cellulosic ethanol to how much energy the fuel produces is much more economically beneficial compared with conventional ethanol, according to the U.S. Department of Energy. And because the usage of corn crops for fuel can compete with the food supply, utilizing waste to make the same fuel is a great alternative, Stender says.
In the Midwest, there’s also the argument that increased corn acreage to accommodate the ethanol market could potentially be harming the environment rather than helping it. In a June 10 article from the St. Louis Post-Dispatch newspaper, scientists claim that the spike in corn production is requiring more fertilizer.
“Unlike soybeans, alfalfa and certain other crops, corn requires heavy applications of fertilizer because it is unable to take nitrogen from the atmosphere,” the article says. The increased use of fertilizer results in more nitrates entering the groundwater. Excessive amounts of nitrates then lead to the growth of phytoplankton and algae bloom, which depletes water of oxygen and kills aquatic vegetation and life. With this potential controversy over the use of corn for ethanol, Florida’s use of citrus waste looks promising.