Unsellable Watermelon Diverted From Waste Stream to Fuel Tank

As the hot summer weather continues to make its presence known while we seek out some manner of a cooling treat, it seems perverse to even consider an end result for watermelon that does not involve it getting hastily and messily devoured. But the fact is, a significant percentage of the annual watermelon crop — about a third of it — never makes it to the produce shelves.

But even though a surprising amount of the annual crop is bird pecked or otherwise marred, rendering it unmarketable, sealing its fate to rot in the fields, a better use for the ugly fruit besides wasting it is in the works: as fuel.

USDA estimates peg the annual loss to spoilage is well over 300,000 tons of watermelon annually, and this could translate into 2.5 million gallons of ethanol. And while this figure represents a mere fraction of the nearly 10 billion gallons of ethanol produced primarily from corn, the watermelon offers a few distinct advantages.

Unlike ethanol production from corn, which requires the addition of significant amounts of water and additives such as nitrogen to achieve ideal conditions for fermentation, watermelon almost strictly by itself is good to go. It contains plenty of water, and while the inherent sugar content is about half of what is otherwise the ideal amount for ethanol production, it's loaded with nitrogen-rich amino acids.

Jim Rausch, of Common Sense Agriculture, LLC, in Texas, who is launching a pilot watermelon-to-ethanol project, puts it all into sweet context in speaking with DiscoveryNews:

"This is not going to replace corn. In that sense it will remain a niche source of biofuel. But unlike algae biodiesel or cellulosic ethanol, it's a right now thing. There's no new technology that needs to be developed to make it economical."

Photo courtesy of USDA, via Wikimedia Commons