Field Pennycress (Thlaspi arvense L.) is a member of the mustard family and may be grown as a winter crop between traditional summer crops to produce renewable biomass for renewable diesel and jet fuel. This paper estimated total annual biofuel production potential of 15 million cubic metres from rotation between corn and soybeans on 16.2 million hectares in the Midwest without impact on food production. This study also investigated the life cycle greenhouse gas (GHG) emissions and energy balance of pennycress-derived Hydroprocessed Renewable Jet (HRJ) fuel and Renewable Diesel (RD). Both system expansion and allocation approaches were applied to distribute environmental impacts among products and coproducts along the life cycle of each biofuel. The life cycle GHG emissions (excluding land use change) for RD and HRJ range from 13 to 41 g MJ(-1) (CO2 eq.) and -18 to 45 g MJ(-1) (CO2 eq.), respectively, depending on how the co-products are credited. The majority of the energy required for each biofuel product is derived from renewable biomass as opposed to non renewable fossil. The fossil energy consumptions are considerably lower than the petroleum fuels. Scenario analyses were also conducted to determine response to model assumptions, including nitrogen fertilizer application rate, nitrogen content in crop residues, and sources of H-2. The results show that pennycress derived biofuels could qualify as advanced biofuels and as biomass-based diesel as defined by the Renewable Fuels Standard (RFS2). (C) 2013 Elsevier Ltd. All rights reserved.