This document summarizes a study comparing the life cycle impacts (LCIs) of wood pellets and switchgrass pellets. The study found that producing 1 ton of wood pellets results in lower impacts for smog, acidification, and global warming potential compared to producing 1 ton of switchgrass pellets. The higher impacts for switchgrass pellets are due to the fossil energy required to pelletize, grow, and transport the switchgrass.