About this Research Topic
Combustion of fossil fuels for energy production has increased the concentration of atmospheric greenhouse gases, and it is considered the main contributor to global warming. In addition, the particulate matter generated by the combustion of fossil fuels is a health hazard. Therefore, one of the sustainable development goals adopted by the United Nations member states is “Affordable and clean energy”, a call for action to preserve the environment. Hydrogen is a promising fuel since it has a high specific energy value and the power generated in hydrogen fuel cells is nonpolluting. Hydrogen production by microorganisms from agricultural and industrial wastes could serve the dual role of producing renewable energy and treating waste.
In order to produce biohydrogen competitively, key challenges need to be addressed such as the cost of production, process design for scale up, effective biohydrogen storage, separation and purification, and biohydrogen integration into end-use applications.
Various low-cost organic substrates have been used as feedstock, with the most-suitable so far being biomass and waste rich in carbohydrates. Also, the hydrogen production rate and yield have improved through optimization of growth conditions and bioreactor configuration (e.g., immobilization of cells), addition of nanoparticles, and genetic engineering. Also, multi-reactor engineering with combinations of the different mechanisms of biohydrogen production (light depended, dark fermentation, or microbial electrolysis cells) has improved hydrogen production.
Furthermore, gas separation membranes to purify biohydrogen have been evaluated. However, the concentration achieved is not yet suitable for direct biohydrogen use in proton-exchange membrane fuel cells. Also, intermetallic compounds have potential for practical biohydrogen separation and storage.
This Research Topic will publish Original Research and Review papers focused on biohydrogen production in the context of sustainable development, including but not limited to, the following fields:
• Microbial community optimization in mixed culture systems
• Genetic engineering of hydrogen-producing microorganisms
• Optimization of operating conditions and bioreactor design
• Biohydrogen purification and storage
• Biohydrogen end-user applications
• Technoeconomic analysis
• Multiple process integration for circular economy
• Environmental impact of biohydrogen
Keywords: renewable energy, hydrogen production, bioenergy, microbial electrolysis cell, techno-economic assessment, production cost, system integration, system design
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.