Uniquely designed three biomass-based integrated sustainable energy systems for comparative evaluation

In this work, three different configurations of an integrated thermal system for hydrogen production utilizing gasification, alkaline electrolysis, and photo-alkaline electrolysis are conceptually developed and thermodynamically analyzed and assessed. Different gasification feedstock options considered include white oak wood, Douglas-fir wood, madrone wood, and pine needles. The Aspen Plus software package is used to conduct corresponding simulations and facilitate the system analysis and performance related calculations. For photo-alkaline electrolysis calculations, the AM1.5G spectrum and the bandgap of copper oxide are also considered. Subsequently, a direct approach is presented for the calculation of the fraction of the solar spectrum and incident irradiance absorbed. The highest hydrogen production is attributed to pine needles at 285 kg/h for a 4500 kg/h biomass feed due to its favorable composition, at efficiencies of 38.07 %, 38.53 %, and a peak of 38.55 % at 17:00 in a diurnal cycle, for gasification, gasification-alkaline electrolysis, and gasification-photo-alkaline-electrolysis system configurations, respectively. • Three systems for hydrogen generation are developed using gasification and electrolysis. • Pine needles achieve the highest hydrogen generation and system efficiency. • Gasification-photoelectrolysis system achieves a peak efficiency of 38.55 %.