Scientists with the United States Department of Agriculture (USDA) recently discovered that watermelon juice is capable of efficient fermentation into ethanol.According to Katie Howell’s story for the New York Times’ Greenwire, watermelon farmers typically leave 20 to 40 percent of their crop in the field because they are not suitable for the market as a result of various rind defects. Estimates show that in 2007 alone, 360,000 tons of watermelons were “wasted” because their rinds were blemished. Despite the fact that a blemished rind does not mean the watermelon is not good, consumers tend to shy away from these watermelons and they never make it off the shelf, if they made it off the farm in the first place.
For the past three years Wayne Fish, a research chemist at USDA’s Lane Research Center in Oklahoma, and his coworkers have been studying whether or not converting watermelon waste into a fuel source is somehow viable. Basically, the ethanol is created from converting captured, concentrated watermelon juice. According to Fish, ‘“We're testing the feasibility to get the numbers out there to be able to do fairly accurate calculations about whether this might be economically feasible."’
In addition to Fish and his team, there is a biofuels company located in College Station, Texas that is working on building a vehicle that could travel to watermelon fields and perform the conversion on-site. According to Jim Rausch, president of Common Sense Agriculture, the company working on the vehicle project, there are other benefits from using watermelon as a fuel source other than putting wasted watermelons to use, such as the fact that ‘"[w]atermelon uses very little nutrients out of soil, it doesn't deplete the soil, and it uses a small amount of water[.]"’ Rausch also argues that the energy input for growing watermelon is much lower than for growing other biofuel feedstocks.
As Howell reports, since this is a relatively new technology and ultimately its main use may be localized to the farm where the watermelons are located and can be converted on-site for farm energy needs, the corn, soybean and cellulosic ethanol producers shouldn’t be terribly concerned about the extra competition at this point in time.
To read the Howell article click here.
Posted:08/28/09
