Hydrogen energy resource: overview of production techniques, economy and application in microgrid systems operation

Hydrogen (H2) fuel is one of eco-friendly resources for delivering de-carbonized and sustainable electricity supply in line with the UN’s Sustainable Development Goals 7 and 13 for affordable and clean energy, and climate change action, respectively. This paper presents a state-of-the art review of the H2 energy resource in terms of its history and evolution, production techniques, global economy, market perspective and application to microgrid systems. It also introduces a systematic classification of the fuel. The production techniques examined include: the thermal approach such as the reforming, gasification and thermochemical processes; the photocatalytic approach otherwise called artificial photosynthesis; the biological and photonic approach that involves the photolysis, photo-fermentation, dark fermentation, CO gas fermentation and biomass valorization processes to produce H2 while the electrical approach is based on the chemical dissociation of electrolytes into their constituent ions by the passage of electric current. A particular attention is paid to the potential of the H2 resource in running some energy generators in microgrid systems such as the internal combustion engines, microturbines, and the fuel cells that are useful for combined heat and power application. The paper introduces different technical configurations, topologies and processes that involve the use of green H2 fuel in generating systems, and the connection of bus bars, power converters, battery bank and the electrical and thermal loads. The paper also presents hybrid fuel cell (FC) and PV system simulation using System Advisor Model (SAM) to showcase the use of H2 fuel in a micogrid. The paper provides insightful directions into the H2 economy, smart electrical grid and the future prospects.