A system configured for the production of at least one product selected from the group consisting of syngas, Fischer-Tropsch synthesis products, power, and chemicals, the system comprising a dual fluidized bed gasification apparatus and at least one apparatus selected from power production apparatus configured to produce power from the gasification product gas, partial oxidation reactors configured for oxidation of at least a portion of the product gas, tar removal apparatus configured to reduce the amount of tar in the product gas, Fischer-Tropsch synthesis apparatus configured to produce Fischer-Tropsch synthesis products from at least a portion of the product gas, chemical production apparatus configured for the production of at least one non-Fischer-Tropsch product from at least a portion of the product gas, and dual fluidized bed gasification units configured to alter the composition of the product gas. Methods of operating the system are also provided.