Using a mix of rulers, calipers, and measuring tapes, a dozen scientists—an aquaculture geek squad of sorts—are sizing up thousands of individual kelp blades recently harvested from offshore seaweed farms in New England in order to find the best specimens for selective breeding. It’s a long, exacting process, but for WHOI scientist Scott Lindell, it’s a key step toward turning the ocean crop into a global energy source for the future. The work will enable scientists to breed better kelp—strains that can tolerate the harsh offshore conditions in which they’re grown. The U.S. Department of Energy’s (DOE) Advanced Research Projects Agency-Energy (ARPA-E) is funding the research, as part of a broader effort aimed at advancing the mass production of seaweed for biofuels. The idea is simple: Grow kelp on a large scale in offshore farms and turn it into biofuels that could one day power millions of homes and cars.