On almond trees, each tiny almond grows inside a shell and a larger, apricot-like hull. In 2017, almond farmers in California grew 2.1 billion pounds of the kernels that are sold in stores, and another 4.3 billion pounds of hulls. “For every pound of almonds we produce, we get two pounds of hulls,” says Danielle Veenstra, an almond farmer who also works with the Almond Board of California, an industry group. “We’re always trying to figure out the best use of these.”
Inside a USDA research building near Berkeley, California, research leader Bill Orts holds up a mottled-looking black plate. It’s “really ugly,” he says. But the rough prototype is the first of its kind, made with recycled plastic and almond shells that were transformed into a charcoal-like black powder in an on-site lab. By adding the powder to bio-based or recycled plastics, the materials get stronger. For the almond industry, it’s one possible way to make the best use of everything grown in an almond orchard.