One of the more environmentally sustainable ways to produce high energy density (oils) liquid transportation fuels is photosynthetic reduction of carbon dioxide into carbohydrates and hydrocarbons and their subsequent conversion into fuels. Photosynthetic carbon capture from the atmosphere combined with bioenergy production (combustion) and subsequent carbon capture and sequestration (BECCS) has also been proposed by the recent Intergovernmental Panel on Climate Change Report as the most effective and economical way to remediate atmospheric greenhouse gasses. To maximize carbon capture efficiency and energy-return-on-investment, we must develop cropping systems that have the greatest aerial biomass yields with the lowest inputs. All photosynthetic organisms, however, convert only a fraction (< 5%) of the solar energy they capture into harvestable chemical energy (reduced carbon or biomass). To increase aerial carbon capture rates and biomass productivity it will be necessary to increase photosynthetic efficiency in plants and algae. We will discuss metabolic engineering strategies to improve photosynthetic efficiency and biomass productivity in algal and plant systems, often borrowing metabolic strategies from one photosynthetic system to transfer into another. These strategies include optimization of photosynthetic light-harvesting antenna size and the introduction of algal inorganic carbon concentrating systems into plants to increase carbon fixation efficiency and biomass yields. To date, these strategies have resulted into up to two fold increases in biomass productivity in algae and crop yields in outdoor field trials.