Nutrient fertilizer requirements for sustainable biomass supply to meet U.S. bioenergy goal

The U.S. Biomass Roadmap set forth a goal that, by the year 2030, biomass will supply energy approximately equivalent to 30% of current petroleum consumption. Here we report on the amount of nutrient fertilizers required to meet the proposed 1-billion tons of sustainable bioenergy biomass production annually. To meet this goal, U.S. agriculture (assuming a scenario with high yield increase and land use change) will have net removals of 40.3, 12.7, and 36.2 Tg (million tons) of N, P2O5, and K2O, respectively. The 1-billion tons of bioenergy biomass production alone will remove 16.9, 5.2, and 18.2 Tg of N, P2O5, and K2O, respectively, from U.S. agricultural land. Considering the efficiencies of fertilizers in soils and the contribution of biomass residuals in fields, the overall bioenergy-focused agriculture would require 58.2, 27.3, and 31.7 Tg of N, P2O5, and K2O fertilizers, respectively; this corresponds to an overall nutrient fertilizer application increase by a factor of 5.5 over the base line (1997). This study indicates an increased need for domestic and/or international production facilities for fertilizers if the goal of the Biomass Roadmap is to be attained.