In just one hour, the sun produces enough energy to meet all human needs for a year. But the challenge has been creating a system that can capture solar energy in an efficient and affordable manner. Now, a team of Berkeley researchers, led by Peidong Yang, professor of materials science and engineering, has developed an “artificial forest,” a model that directly converts sunlight into chemical fuels in a process that mimics photosynthesis. Their technology—the first fully integrated nanosystem for artificial photosynthesis—uses artificial nanowire trees, including silicon trunks and titanium oxide branches, for solar-to-fuel conversion. Densely packed, the trees are designed to resemble a forest, minimizing sunlight reflection and boosting the surface area for fuel-producing reactions. The team believes their system is the most efficient and economical to date, and have designed it to be modular, allowing for individual components to be swapped out as new versions are developed.