Algae are highly efficient photosynthesisers which can be grown on non-arable land, thereby avoiding competition with food production. This makes them a potential source for a range of genuinely sustainable biofuels including carbon-based fuels and hydrogen. At the same time, as rapidly growing eukaryotes, they have biotechnological potential for both natural and recombinant high value products especially suited to their photosynthetic physiology. Our laboratory focuses on the challenge of developing large scale algaculture including strain selection and adaption, and the ability to make precision changes that yield desirable traits. Genetic manipulation, including photosynthetic antenna modulation and improvements to hydrogen production, has demonstrated that bioreactor efficiency can be improved, while recent advances in genome editing promise to vastly increase the scope and power of algal biotechnology. An advanced algae pilot plant provides a testbed for proving these ideas in scale-up conditions while TEA and LCA capabilities allow the identification of key opportunities to optimise processes. Although GM modifications of algae are guided by existing knowledge of photosynthetic physiology, they sometimes produce unexpected results which challenge and inform our understanding of the regulation and biological framework of photosynthesis.