A startup backed and incubated by Bill Gates’ Breakthrough Energy Ventures has engineered a hybrid technology that combines engineering with natural photosynthesis processes to remove carbon dioxide from the atmosphere and store it underground. …Graphyte takes waste biomass like discarded wood residue or rice hulls, dries and sterilizes it to prevent decomposition. It then condenses it into dense carbon blocks, wraps it in a proprietary polymer barrier and stores it underground in an engineered storage site. …Graphyte says its levelized cost of production is currently under $100 per ton, a moonshot target for carbon removal that direct air capture is still far from achieving. It also requires a tenth of the energy of direct air capture, and the carbon blocks are projected to be durable for over a thousand years, due in part to the proprietary polymer barrier protecting them, according to Rogers.