The present invention provides a photobiological ethanol production and harvesting technology using greenhouse distillation systems with designer photosynthetic organisms, such as designer transgenic oxyphotobacteria. The designer oxyphotobacteria are created such that the endogenous photobiological regulation mechanism is tamed, and the reducing power (NADPH) and energy (ATP) acquired from the photosynthetic process are used for synthesis of ethanol (CH3CH2OH) directly from carbon dioxide (CO2) and water (H2O). The designer use of a pair of NADPH-dependent vs. NAD-dependent glyceraldehyde-3-phosphate dehydrogenases in the pathway designs offers a special cyclic “transhydrogenase” redox-shuttle function to convert NADPH to NADH for enhanced photobiological ethanol production. Through combined use of a designer photosynthetic organism with a greenhouse distillation system, the waste solar heat associated with the photobiological ethanol-production process is utilized in harvesting the produced ethanol. In addition to production and harvesting of ethanol, use of the technology can also produce intermediate metabolites and freshwater from seawater.
