Microalgal biodiesel and the Renewable Fuel Standard's greenhouse gas requirement

► Conducted a comparative life cycle assessment (LCA) on four different microalgal biodiesel production conditions. ► Evaluated environmental impacts using a process LCA model with Monte Carlo simulation. ► None of the investigated production conditions meets the Renewable Fuel Standard's greenhouse gas requirement. ► The reduction of greenhouse gas emissions does not always result in the reduction of other environmental impacts.