Across all parameters, both the economic and environmental sustainability of oilcane is most sensitive to the dry biomass yield (Figure and S6; SI). Although increasing oil content at the expense of a modest reduction in biomass yield can result in a net financial benefit, the best performing oilcane line (balancing oil content and biomass yield; Oilcane 1566) and the oilcane line with the highest oil content (Oilcane 1580) have such large reductions in dry biomass yield (relative to sugarcane) that they have similar or greater MBSPs and carbon intensities compared to sugarcane (Figure ). The reduced biomass yield of current oilcane prototypes is a result of high constitutive expression of lipogenic genes WRI and DGAT, which lead to either elevated levels of toxic free fatty acids (caused by high WRI expression) or depletion of phosphatidylglycerol needed for thylakoid membranes (caused by high DGAT expression). Higher biomass yields and lipid contents may be achieved if alternative regulatory elements are implemented to fine-tune the spatial and temporal expression of lipogenic genes. Research in the development of oil-accumulating feedstocks may direct efforts towards regulating lipogenic gene expression to sustain both high biomass yield and oil contents. In addition to oilcane, researchers are currently developing new lines of oil-accumulating sweet-sorghum 57 (up to 3 dw % oil in stems) which have not exhibited growth penalties (field trials still on-going) and oilaccumulating energycane (up to 1.5 dw % TAG in leaves) which natively have greater biomass yield than sugarcane. Once field trials are completed for these new feedstocks, future assessments may seek to evaluate their sustainability for the production of biofuel and bioproducts.