Sustainability of Biohydrogen Production Using Engineered Algae as a Source

Abstract

The increased scarcity of fossil fuels and concerns over climate change have focused attention on alternative energy and the production of renewable fuels. Hydrogen is a promising substitute as an energy carrier to the fossil fuels, since it has high conversion efficiency and high energy content and is environmentally friendly. Nowadays, hydrogen is mostly produced via chemical reformation of fossil fuels; therefore, the biological production of hydrogen is seen as very attractive. Biological hydrogen production represents a renewable means of generating this biofuel and can be performed by a wide range of microorganisms from strict anaerobic bacteria to eukaryotic green algae. Different strains of photoautotrophic green algae have the remarkable ability to reduce protons to H2 using light energy. Photobiological hydrogen production by green algae is particularly attractive due to the fact that water and solar energy as main inputs for the process are plentiful on our planet. In this chapter we are focusing on the recent developments in photobiological H2 production by green algae with highlights on the barriers that prevent H2 production and how those limitations can be addressed, through genetic and metabolic engineering.