In California, biofuel to run cars and generators could come from large swaths of seaweed grown in the open ocean. That’s the vision of a new project being led by Marine BioEnergy, Inc., in collaboration with PNNL and the Scripps Institution of Oceanography at University of California, San Diego.
Marine BioEnergy has proposed a patented method to grow one of the fastest producers of biomass, giant kelp, in the open ocean. Sunshine and space are abundant in the open ocean, but waters are too deep there for kelp to grow on the sea floor. Instead, Marine Bioenergy will develop technology to enable the eventual attachment of kelp to large grids towed by inexpensive robotic submarines that cycle between sunlight at the sea surface and nutrients in deeper waters. A team led by Scripps’ James Leichter will develop and test critical technology for open ocean cultivation of kelp.
Once farmed, the kelp will be turned into biocrude oil and other hydrocarbon liquids through a conversion process developed by PNNL. Led by Laboratory Fellow Douglas Elliott, the PNNL team will develop a multi-step method that will combine hydrothermal liquefaction, catalytic hydrothermal gasification and hydrotreating — all of which involve changes in temperature, pressure and water — to convert biomass. PNNL’s method will cost-effectively turn kelp into hydrocarbons that are ready for final processing at a commercial oil refinery.
ARPA-E awarded the project a total of about $2.1 million over three years, with approximately $479,000 going to PNNL.