In Reinventing Fire’s 2050 outlook, biomass provides a feedstock for producing biofuels in the Industry sector for use in transportation; it fuels some generation in power plants, chiefly combined heat and power in industry and generally using waste streams; and it provides some heat in industrial processes and buildings. All 2050 U.S. biomass demand can be served by five categories of nonedible feedstock (in order of increasing cost): agricultural residue, mill residue, non-cropland energy crops, municipal solid waste, and forestry residue. No cropland or edible feedstock is required. Biomass totals are based on current supply data extrapolated to 2050 according to growth metrics appropriate to each category of feedstock (see Transportation sector methodology for details and sources). Algae (not shown here) could provide a significant additional source of biomass with continued progress in overcoming cost and technology challenges.