(248b) The Scope of Using Concentrated Solar Energy to Produce Liquid Fuels From Biomass

In a fossil-fuel deprived world, liquid fuels from biomass, or biofuels, can play a major role in satisfying the energy needs of the transportation sector in a sustainable manner. The specific extent of biofuels usage would depend on, among other things, the associated life-cycle CO₂ balance and the land area requirements for the feedstock. Both of these issues can be addressed by maximizing the quantity of biofuel produced from the available biomass. This presentation discusses the scope of using concentrated solar energy as the heat source, in combination with biomass for efficient biofuel production. Details of a synergistic thermochemical process envisioned, involving high temperature biomass steam gasification followed by Fischer-Tropsch (FT) processing to biofuels, are presented. In addition to an increase in the estimated biofuel yield compared to conventional methods, the process offers a means of storing additional solar energy in an easy-to-use form, by upgrading the calorific value of the biomass feedstock. Enhancements to the above process presented, include several scenarios of supplemental use of hydrogen produced from solar energy, in order to convert the residual CO₂ to additional biofuel in the least solar energy intensive manner possible. Overall, the integrated use of hydrogen and concentrated solar energy (heat), results in a maximum threefold increase in the biofuel produced compared to conventional gasification processes.